2016 |
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| 130. | Tae-Wan Kim; Byeong-Yong Park; Seung-Young Park; Seong-Ook Park Calculation of Magnetization and Permeability Tensor of a Partially Magnetized Cylindrical Ferrite Resonator Journal Article IEEE Magnetics Letters, 7 , 2016. @article{Kim2016d, title = {Calculation of Magnetization and Permeability Tensor of a Partially Magnetized Cylindrical Ferrite Resonator}, author = {Tae-Wan Kim and Byeong-Yong Park and Seung-Young Park and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07414421.pdf}, doi = {10.1109/LMAG.2016.2532319}, year = {2016}, date = {2016-02-19}, journal = {IEEE Magnetics Letters}, volume = {7}, abstract = {A accurate method of calculating a magnetization and permeability tensor of ferrites is proposed in this paper. We introduce a cylindrical ferrite resonator that is located between parallel metal plates. We theoretically derive exact eigenvalue equations for the mode-splitting phenomenon of the HE111 mode. We also show that the mode-splitting behavior depends on a single magnetization value of the ferrite. The magnetization and permeability tensor components are computed from the measured resonant frequencies of the resonator. We present an analysis of cylindrical ferrite resonator and its experimental results.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A accurate method of calculating a magnetization and permeability tensor of ferrites is proposed in this paper. We introduce a cylindrical ferrite resonator that is located between parallel metal plates. We theoretically derive exact eigenvalue equations for the mode-splitting phenomenon of the HE111 mode. We also show that the mode-splitting behavior depends on a single magnetization value of the ferrite. The magnetization and permeability tensor components are computed from the measured resonant frequencies of the resonator. We present an analysis of cylindrical ferrite resonator and its experimental results. |
| 129. | Dong-Hyuk Choi; Seong-Ook Park Active integrated antenna using T‐shaped microstip‐line‐fed slot antenna Journal Article Microwave and Optical Technology Letters, 48 , 2016. @article{Choi2016, title = {Active integrated antenna using T‐shaped microstip‐line‐fed slot antenna}, author = {Dong-Hyuk Choi and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Choi_et_al-2006-Microwave_and_Optical_Technology_Letters.pdf}, doi = {10.1002/mop.21351}, year = {2016}, date = {2016-02-01}, journal = {Microwave and Optical Technology Letters}, volume = {48}, abstract = {An active integrated antenna (AIA), which consists of a T‐shaped microstrip‐line‐fed slot antenna, is proposed. Since the designed antenna has an electromagnetically coupled feedback loop, it can easily solve the problem of DC isolation between ports of the amplifier. The fabricated parallel feedback antenna oscillator shows stable oscillation at a frequency of 10.05 GHz. The measured EIRP is 37.79 mW, and the cross‐polarization levels are at least −15‐dB lower than those of co‐polarization for all directions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An active integrated antenna (AIA), which consists of a T‐shaped microstrip‐line‐fed slot antenna, is proposed. Since the designed antenna has an electromagnetically coupled feedback loop, it can easily solve the problem of DC isolation between ports of the amplifier. The fabricated parallel feedback antenna oscillator shows stable oscillation at a frequency of 10.05 GHz. The measured EIRP is 37.79 mW, and the cross‐polarization levels are at least −15‐dB lower than those of co‐polarization for all directions. |
| 128. | Dong-Uk Sim; Jeong-Ho Ju; Jong-Hwa Kwon; Seong-Ook Park An ultracompact CRLH-TL bandpass filter for VHF applications Journal Article Microwave and Optical Technology Letters, 58 , pp. 694 - 697, 2016. @article{Sim2016b, title = {An ultracompact CRLH-TL bandpass filter for VHF applications}, author = {Dong-Uk Sim and Jeong-Ho Ju and Jong-Hwa Kwon and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Sim_et_al-2016-Microwave_and_Optical_Technology_Letters.pdf}, doi = {10.1002/mop.29641}, year = {2016}, date = {2016-01-27}, journal = {Microwave and Optical Technology Letters}, volume = {58}, pages = {694 - 697}, abstract = {This article proposes a new design approach to an ultracompact composite right‐/left‐handed transmission line (CRLH‐TL) bandpass filter with good passband and very broad stopband performances. In order to reduce the size, a series connection of the interdigital capacitor and shorted spiral inductor for realizing CRLH‐TL is adopted and optimized to create the target Terrestrial‐Digital Multimedia Broadcasting (T‐DMB, 174–216 MHz) bandpass filtering. T‐DMB was developed in South Korea. The results of a Bloch impedance analysis suggest that the proposed approach generates good impedance matching. The proposed filter has overall dimensions of λg/19 by λg/34 in terms of a center frequency of 180 MHz, a 3 dB fractional bandwidth of over 28%, an insertion loss of much lower than 2 dB, and a good return loss performance in the predicted and measured results.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This article proposes a new design approach to an ultracompact composite right‐/left‐handed transmission line (CRLH‐TL) bandpass filter with good passband and very broad stopband performances. In order to reduce the size, a series connection of the interdigital capacitor and shorted spiral inductor for realizing CRLH‐TL is adopted and optimized to create the target Terrestrial‐Digital Multimedia Broadcasting (T‐DMB, 174–216 MHz) bandpass filtering. T‐DMB was developed in South Korea. The results of a Bloch impedance analysis suggest that the proposed approach generates good impedance matching. The proposed filter has overall dimensions of λg/19 by λg/34 in terms of a center frequency of 180 MHz, a 3 dB fractional bandwidth of over 28%, an insertion loss of much lower than 2 dB, and a good return loss performance in the predicted and measured results. |
2015 |
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| 127. | Seong-Jin Park; Dong-Hun Shin; Seong-Ook Park Low Side-Lobe Substrate-Integrated-Waveguide Antenna Array Using Broadband Unequal Feeding Network for Millimeter-Wave Handset Device Journal Article IEEE Transactions on Antennas and Propagation, 64 , pp. 923 - 932, 2015. @article{Park2015, title = {Low Side-Lobe Substrate-Integrated-Waveguide Antenna Array Using Broadband Unequal Feeding Network for Millimeter-Wave Handset Device}, author = {Seong-Jin Park and Dong-Hun Shin and Seong-Ook Park }, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07368120.pdf}, doi = {10.1109/TAP.2015.2513075}, year = {2015}, date = {2015-12-29}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {64}, pages = {923 - 932}, abstract = {A low side-lobe substrate-integrated-waveguide (SIW) antenna array is presented at the 28-GHz band using broadband unequal feeding network for millimeter-wave (mm-wave) handset devices. The ground-plane size of the proposed antenna is fixed to half of the size of the Samsung Galaxy Note 4. The antenna array has been implemented with a multilayer structure created by stacking three substrates and a copper plate. An 8-way SIW feeding network with broadband 4-stage T-junction dividers and a cavity-backed antenna are investigated to obtain broadband performance. The proposed unequal T-junction dividers with phase compensation are introduced and designed for various output ratios. Applying Taylor beam-pattern synthesis in the 8-way SIW feeding network, low side-lobe performance is achieved. The measured result of the fabricated antenna has 2.3 GHz bandwidth within S 11 <; - 10 dB. The fabricated antenna can be performed with a gain up to 13.97 dBi with a low cross-polarization and symmetrical fan beam radiation patterns with low side-lobe levels. Most of the measured results are validated with the simulated results. The proposed antenna array provides low cost, broadband performance, and good radiation performances with low side-lobe levels for mm-wave handset devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A low side-lobe substrate-integrated-waveguide (SIW) antenna array is presented at the 28-GHz band using broadband unequal feeding network for millimeter-wave (mm-wave) handset devices. The ground-plane size of the proposed antenna is fixed to half of the size of the Samsung Galaxy Note 4. The antenna array has been implemented with a multilayer structure created by stacking three substrates and a copper plate. An 8-way SIW feeding network with broadband 4-stage T-junction dividers and a cavity-backed antenna are investigated to obtain broadband performance. The proposed unequal T-junction dividers with phase compensation are introduced and designed for various output ratios. Applying Taylor beam-pattern synthesis in the 8-way SIW feeding network, low side-lobe performance is achieved. The measured result of the fabricated antenna has 2.3 GHz bandwidth within S 11 <; - 10 dB. The fabricated antenna can be performed with a gain up to 13.97 dBi with a low cross-polarization and symmetrical fan beam radiation patterns with low side-lobe levels. Most of the measured results are validated with the simulated results. The proposed antenna array provides low cost, broadband performance, and good radiation performances with low side-lobe levels for mm-wave handset devices. |
| 126. | Byeong-Yong Park; Tae-Wan Kim; Seong-Ook Park Metallic post-array loaded cylindrical dielectric resonator antenna Journal Article The Journal of Engineering, pp. 1 - 3, 2015. @article{Park2015b, title = {Metallic post-array loaded cylindrical dielectric resonator antenna}, author = {Byeong-Yong Park and Tae-Wan Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/JOE.2015.0182.pdf}, doi = {10.1049/joe.2015.0182}, year = {2015}, date = {2015-11-27}, journal = {The Journal of Engineering}, pages = {1 - 3}, abstract = {An investigation of a novel cylindrical dielectric resonator antenna (DRA) configuration has been carried out. It is shown that two resonances including the full- and half-cylindrical HE 11δ-like modes can coexist simultaneously at different frequencies by placing a metallic post array in the resonator. Moreover, compared with the conventional HE 11δ mode cylindrical DRA having the same size, the proposed antenna operates in lower frequency band and shows improved bandwidth. The experimental results including the return loss and the radiation patterns are demonstrated.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An investigation of a novel cylindrical dielectric resonator antenna (DRA) configuration has been carried out. It is shown that two resonances including the full- and half-cylindrical HE 11δ-like modes can coexist simultaneously at different frequencies by placing a metallic post array in the resonator. Moreover, compared with the conventional HE 11δ mode cylindrical DRA having the same size, the proposed antenna operates in lower frequency band and shows improved bandwidth. The experimental results including the return loss and the radiation patterns are demonstrated. |
| 125. | Dong-Hun Shin; Seong-Jin Park; Jae-We Ahan; Ki-Woong Han; Seong-Ook Park Design of shorted parasitic rhombic array antenna for 24 GHz rear and side detection system Journal Article IET Microwaves Antennas & Propagation, 9 , pp. 1581 - 1586, 2015. @article{Shin2015, title = {Design of shorted parasitic rhombic array antenna for 24 GHz rear and side detection system}, author = {Dong-Hun Shin and Seong-Jin Park and Jae-We Ahan and Ki-Woong Han and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07328558.pdf}, doi = {10.1049/iet-map.2015.0086}, year = {2015}, date = {2015-11-16}, journal = {IET Microwaves Antennas & Propagation}, volume = {9}, pages = {1581 - 1586}, abstract = {A novel microstrip patch antenna is proposed for automotive application. The antenna design has been investigated through both the parametric study and the demonstration of surface currents on the antenna structure. The surface currents related to the co-polarisation increased, and those related to the cross-polarisation is reduced by attaching shorted parasitic element. The four types of single antenna are designed to compare of gain and cross-polarisation level. The cross-polarisation level of proposed antenna has been reduced by 5.9 dB compared with the rhombic antenna. The rhombic array antenna and proposed array antenna were fabricated and tested for input reflection coefficient and radiation performance. The measured and simulated results have been presented and discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A novel microstrip patch antenna is proposed for automotive application. The antenna design has been investigated through both the parametric study and the demonstration of surface currents on the antenna structure. The surface currents related to the co-polarisation increased, and those related to the cross-polarisation is reduced by attaching shorted parasitic element. The four types of single antenna are designed to compare of gain and cross-polarisation level. The cross-polarisation level of proposed antenna has been reduced by 5.9 dB compared with the rhombic antenna. The rhombic array antenna and proposed array antenna were fabricated and tested for input reflection coefficient and radiation performance. The measured and simulated results have been presented and discussed. |
| 124. | Jung-Hwan Hwang; Tae-Wook Kang; Youn-Tae Kim; Seong-Ook Park Measurement of Transmission Properties of HBC Channel and Its Impulse Response Model Journal Article IEEE Transactions on Instrumentation and Measurement, 65 , pp. 177 - 188, 2015. @article{Hwang2015, title = {Measurement of Transmission Properties of HBC Channel and Its Impulse Response Model}, author = {Jung-Hwan Hwang and Tae-Wook Kang and Youn-Tae Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07273899.pdf}, doi = {10.1109/TIM.2015.2476236}, year = {2015}, date = {2015-09-22}, journal = {IEEE Transactions on Instrumentation and Measurement}, volume = {65}, pages = {177 - 188}, abstract = {In human body communication (HBC), the human body is used as a medium for transmitting data between devices in order to replace wired and wireless technologies. This paper presents the measurement results on the transmission properties of an HBC channel and an impulse response model for the HBC channel. The HBC channel was measured with respect to multiple subjects, and the channel parameters were then obtained to analyze the subject dependency of the HBC channel. The HBC channel was modeled using impulse responses that were obtained from the measured channels. The measurement results and the impulse response model can be effectively used to estimate the performance of HBC devices, which is significantly influenced by an HBC channel.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In human body communication (HBC), the human body is used as a medium for transmitting data between devices in order to replace wired and wireless technologies. This paper presents the measurement results on the transmission properties of an HBC channel and an impulse response model for the HBC channel. The HBC channel was measured with respect to multiple subjects, and the channel parameters were then obtained to analyze the subject dependency of the HBC channel. The HBC channel was modeled using impulse responses that were obtained from the measured channels. The measurement results and the impulse response model can be effectively used to estimate the performance of HBC devices, which is significantly influenced by an HBC channel. |
| 123. | AK Ayra; Rao Shahid Aziz; Seong-Ook Park Planar ultra-wideband printed wide-slot antenna using fork-like tuning stub Journal Article Electronics Letters, 51 , pp. 550 - 551, 2015. @article{Ayra2015, title = {Planar ultra-wideband printed wide-slot antenna using fork-like tuning stub}, author = {AK Ayra and Rao Shahid Aziz and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07073714.pdf}, doi = {10.1049/el.2015.0428}, year = {2015}, date = {2015-04-02}, journal = {Electronics Letters}, volume = {51}, pages = {550 - 551}, abstract = {A printed wide-slot antenna with a centred rectangular parasitic patch, fed by a fork-like tuning stub with rectangular parasitic elements adjacent to the main feed line is proposed and discussed. The proposed wide-slot antenna eliminates the need of rotation of the slot and parasitic patches both in the ground plane for the improvement in impedance bandwidth. The experimental results indicate that the presented antenna has a bandwidth (-10 dB) of more than 148% ranging from 2 to 13.5 GHz. The total size of the proposed antenna configuration is 44.3 × 44.3 × 0.508 mm3.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A printed wide-slot antenna with a centred rectangular parasitic patch, fed by a fork-like tuning stub with rectangular parasitic elements adjacent to the main feed line is proposed and discussed. The proposed wide-slot antenna eliminates the need of rotation of the slot and parasitic patches both in the ground plane for the improvement in impedance bandwidth. The experimental results indicate that the presented antenna has a bandwidth (-10 dB) of more than 148% ranging from 2 to 13.5 GHz. The total size of the proposed antenna configuration is 44.3 × 44.3 × 0.508 mm3. |
| 122. | Dong-Uk Sim; Jong-Hwa Kwon; Seong-Ook Park Design of electromagnetic wave absorber using periodic structure and method to broaden its bandwidth based on equivalent circuit-based analysis Journal Article IET Microwaves Antennas & Propagation, 9 , pp. 142 - 150, 2015. @article{Sim2015, title = {Design of electromagnetic wave absorber using periodic structure and method to broaden its bandwidth based on equivalent circuit-based analysis}, author = {Dong-Uk Sim and Jong-Hwa Kwon and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07027647.pdf}, doi = {10.1049/iet-map.2013.0487}, year = {2015}, date = {2015-02-05}, journal = {IET Microwaves Antennas & Propagation}, volume = {9}, pages = {142 - 150}, abstract = {A new broadband electromagnetic wave absorber based on a periodic surface and a method to increase its absorption bandwidth is proposed. The proposed absorber structure shows broadband characteristics, and its bandwidth is improved by generating additional resonances through a reasonable approach. To provide an understanding of the logical design procedure, an analytical method to determine the sheet resistance and new equivalent circuit models for analysing the impedance are both presented. From the analysis, it is shown that the exact range of the sheet resistance corresponding to the desired absorption level can be efficiently estimated for the resonance of the structure. For the verification of this approach to obtain an efficient design, as well as the functionality of both the absorber and the proposed method, experimental results are demonstrated along with analytical and computational results. The final measured results using the proposed method show a broadband reflectivity response, with a fractional bandwidth of approximately 93% below -10 dB and a bandwidth increase of 17%.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new broadband electromagnetic wave absorber based on a periodic surface and a method to increase its absorption bandwidth is proposed. The proposed absorber structure shows broadband characteristics, and its bandwidth is improved by generating additional resonances through a reasonable approach. To provide an understanding of the logical design procedure, an analytical method to determine the sheet resistance and new equivalent circuit models for analysing the impedance are both presented. From the analysis, it is shown that the exact range of the sheet resistance corresponding to the desired absorption level can be efficiently estimated for the resonance of the structure. For the verification of this approach to obtain an efficient design, as well as the functionality of both the absorber and the proposed method, experimental results are demonstrated along with analytical and computational results. The final measured results using the proposed method show a broadband reflectivity response, with a fractional bandwidth of approximately 93% below -10 dB and a bandwidth increase of 17%. |
| 121. | Chang-Hee Hyoung; Jung-Hwan Hwang; Sung-Wen Kang; Seong-Ook Park A Feasibility Study on the Adoption of Human Body Communication for Medical Service Journal Article IEEE Transactions on Circuits and Systems II: Express Briefs, 62 , pp. 169 - 173, 2015. @article{Hyoung2015, title = {A Feasibility Study on the Adoption of Human Body Communication for Medical Service}, author = {Chang-Hee Hyoung and Jung-Hwan Hwang and Sung-Wen Kang and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/07001176.pdf}, doi = {10.1109/TCSII.2014.2387631}, year = {2015}, date = {2015-01-05}, journal = {IEEE Transactions on Circuits and Systems II: Express Briefs}, volume = {62}, pages = {169 - 173}, abstract = {A feasibility study on the adoption of human body communication (HBC) for medical service is presented. The electrical specifications of HBC for medical service were reviewed. The ratio of the leakage current into the heart to the output current of a capsule-type transmitter and the propagation loss in the channel were simulated using an anatomical body model. The in-body to on-body channel loss for HBC was provided by electromagnetic simulation from the capsule-type transmitter in the stomach to receiving electrodes on the abdominal region. An analog front end with a sensitivity of 37 μVpp was developed, which showed an improvement of 21 dB against the best report. The 14 mm × 26 mm capsule-type transmitter was implemented, and preclinical experiment was conducted using a live pig. The proposed system successfully transferred data from the capsule-type transmitter in a stomach to the electrodes on the butt and the low jaw of the pig at a high rate of 2 Mb/s at a distance of 90 cm without packet error.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A feasibility study on the adoption of human body communication (HBC) for medical service is presented. The electrical specifications of HBC for medical service were reviewed. The ratio of the leakage current into the heart to the output current of a capsule-type transmitter and the propagation loss in the channel were simulated using an anatomical body model. The in-body to on-body channel loss for HBC was provided by electromagnetic simulation from the capsule-type transmitter in the stomach to receiving electrodes on the abdominal region. An analog front end with a sensitivity of 37 μVpp was developed, which showed an improvement of 21 dB against the best report. The 14 mm × 26 mm capsule-type transmitter was implemented, and preclinical experiment was conducted using a live pig. The proposed system successfully transferred data from the capsule-type transmitter in a stomach to the electrodes on the butt and the low jaw of the pig at a high rate of 2 Mb/s at a distance of 90 cm without packet error. |
2014 |
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| 120. | Jung-Hwan Hwang; Tae-Wook Kang; Youn-Tae Kim; Seong-Ook Park Empirical Channel Model for Human Body Communication Journal Article IEEE Antennas and Wireless Propagation Letters, 14 , pp. 694 - 697, 2014. @article{Hwang2014, title = {Empirical Channel Model for Human Body Communication}, author = {Jung-Hwan Hwang and Tae-Wook Kang and Youn-Tae Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06975066.pdf}, doi = {10.1109/LAWP.2014.2377051}, year = {2014}, date = {2014-12-04}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {14}, pages = {694 - 697}, abstract = {In this letter, an empirical channel model for human body communication (HBC) is presented based upon impulse response. For a channel model over a wide range of frequencies between 5 and 80 MHz, the amplitude of an impulse response is modeled with a random variable at each sampling point; the random variable is found using empirically obtained impulse responses with respect to multiple subjects of 70 human subjects. This empirical channel model is obtained when a signal transmitter and receiver are located on opposite hands. However, it provides a practical way to estimate the performance of HBC systems within an environment of multiple users and various devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this letter, an empirical channel model for human body communication (HBC) is presented based upon impulse response. For a channel model over a wide range of frequencies between 5 and 80 MHz, the amplitude of an impulse response is modeled with a random variable at each sampling point; the random variable is found using empirically obtained impulse responses with respect to multiple subjects of 70 human subjects. This empirical channel model is obtained when a signal transmitter and receiver are located on opposite hands. However, it provides a practical way to estimate the performance of HBC systems within an environment of multiple users and various devices. |
| 119. | Yun-Seok Noh; Rao Shahid Aziz; Myung-Hun Jeong; Dae-Hwan Jung; AK Ayra; Seong-Ook Park Rayleigh Fading Channel Characterization Using K-Band FMCW Radar in Reverberation Chamber Journal Article Progress In Electromagnetics Research M, 39 , pp. 193 - 201, 2014. @article{Noh2014, title = {Rayleigh Fading Channel Characterization Using K-Band FMCW Radar in Reverberation Chamber}, author = {Yun-Seok Noh and Rao Shahid Aziz and Myung-Hun Jeong and Dae-Hwan Jung and AK Ayra and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/14102803.pdf}, doi = {10.2528/PIERM14102803}, year = {2014}, date = {2014-12-03}, journal = {Progress In Electromagnetics Research M}, volume = {39}, pages = {193 - 201}, abstract = {This paper investigates the channel characterization of Rayleigh fading channel using K-band frequency-modulated continuous wave (FMCW) radar system. An IF (intermediate frequency) signal of K-band FMCW radar can be treated as time and frequency domain signals due to a unique property of linear frequency modulation (LFM). First, channel sounder FMCW radar stability has been confirmed by measuring power flatness of transmitted radio frequency signal and estimated range in anechoic chamber before conducting the experiment for channel characterization of Rayleigh fading channel. Next, the measurement setup has been conducted in reverberation chamber which emulates multipath fading phenomena. In reverberation chamber, four different cases have been examined by changing the boundary conditions inside it with and without flat microwave absorbers. This investigation leads to obtained scattered plots, normalized propagation delay profiles (PDPs), mean excess delay, root-mean-square (RMS) delay spread and envelope distribution of Rayleigh fading channel at about 24.591 GHz.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper investigates the channel characterization of Rayleigh fading channel using K-band frequency-modulated continuous wave (FMCW) radar system. An IF (intermediate frequency) signal of K-band FMCW radar can be treated as time and frequency domain signals due to a unique property of linear frequency modulation (LFM). First, channel sounder FMCW radar stability has been confirmed by measuring power flatness of transmitted radio frequency signal and estimated range in anechoic chamber before conducting the experiment for channel characterization of Rayleigh fading channel. Next, the measurement setup has been conducted in reverberation chamber which emulates multipath fading phenomena. In reverberation chamber, four different cases have been examined by changing the boundary conditions inside it with and without flat microwave absorbers. This investigation leads to obtained scattered plots, normalized propagation delay profiles (PDPs), mean excess delay, root-mean-square (RMS) delay spread and envelope distribution of Rayleigh fading channel at about 24.591 GHz. |
| 118. | Young-Guk Kim; Seong-Ook Park A wideband dual polarization base station antenna Journal Article Microwave and Optical Technology Letters, 57 , pp. 22 - 26, 2014. @article{Kim2014, title = {A wideband dual polarization base station antenna}, author = {Young-Guk Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Kim_et_al-2015-Microwave_and_Optical_Technology_Letters.pdf}, doi = {doi.org/10.1002/mop.28767}, year = {2014}, date = {2014-11-18}, journal = {Microwave and Optical Technology Letters}, volume = {57}, pages = {22 - 26}, abstract = {This article investigates the slotted bow‐tie dual‐polarization antenna with achieving the wide band. The proposed antenna consists of upper antenna and lower antenna in one PCB substrate. This antenna achieves a −10 dB return loss within the operating band of 1.6–2.3 GHz, which has a 700 MHz bandwidth. Isolation between antenna 1 and antenna 2 is about −30 dB within the operating frequency band. Antenna 1 and 2's gains are above 8 dBi in the entire frequency bandwidth.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This article investigates the slotted bow‐tie dual‐polarization antenna with achieving the wide band. The proposed antenna consists of upper antenna and lower antenna in one PCB substrate. This antenna achieves a −10 dB return loss within the operating band of 1.6–2.3 GHz, which has a 700 MHz bandwidth. Isolation between antenna 1 and antenna 2 is about −30 dB within the operating frequency band. Antenna 1 and 2's gains are above 8 dBi in the entire frequency bandwidth. |
| 117. | Viet-Anh Nguyen; Rao Shahid Aziz; Seong-Ook Park; Giwan Yoon A Design of Multiband, Dual-Polarization, Beam-Switchable Dual-antenna for Indoor Base Stations Journal Article Progress in Electromagnetics Research, 149 , pp. 147 - 160, 2014. @article{Nguyen2014b, title = {A Design of Multiband, Dual-Polarization, Beam-Switchable Dual-antenna for Indoor Base Stations}, author = {Viet-Anh Nguyen and Rao Shahid Aziz and Seong-Ook Park and Giwan Yoon}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/14073103.pdf}, year = {2014}, date = {2014-10-14}, journal = {Progress in Electromagnetics Research}, volume = {149}, pages = {147 - 160}, abstract = {A novel multiband, dual-polarization, beam-switched dual-antenna design, covering some LTE and WLAN bands, has been proposed for indoor base stations. The proposed design consists mainly of dual modified monopole antennas. The horizontal antenna consists of four printed monopole elements, and the control circuit using p-i-n diodes has been implemented for feeding to each monopole element. The vertical monopole antenna beam patterns are controlled by reconfigurable frequency selective reflectors (RFSR) technique. The p-i-n diodes have been utilized for switching mechanism to feed the four RFSR. The measured and simulated results indicate that the antenna system possesses multiband and dual polarization. It has been observed from the simulated and measured reflection coefficients |S11| that the presented dual antenna system supports both LTE (1.7-2.1 GHz) and WLAN (2.5 GHz and 5.8 GHz) band frequencies. Moreover, the radiation characteristics show dual-polarization behaviors of the presented antenna system and beam switching states suitable for small cell indoor-base stations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A novel multiband, dual-polarization, beam-switched dual-antenna design, covering some LTE and WLAN bands, has been proposed for indoor base stations. The proposed design consists mainly of dual modified monopole antennas. The horizontal antenna consists of four printed monopole elements, and the control circuit using p-i-n diodes has been implemented for feeding to each monopole element. The vertical monopole antenna beam patterns are controlled by reconfigurable frequency selective reflectors (RFSR) technique. The p-i-n diodes have been utilized for switching mechanism to feed the four RFSR. The measured and simulated results indicate that the antenna system possesses multiband and dual polarization. It has been observed from the simulated and measured reflection coefficients |S11| that the presented dual antenna system supports both LTE (1.7-2.1 GHz) and WLAN (2.5 GHz and 5.8 GHz) band frequencies. Moreover, the radiation characteristics show dual-polarization behaviors of the presented antenna system and beam switching states suitable for small cell indoor-base stations. |
| 116. | Dohoon Kim; Hyo-J. Eom; Seong-Ook Park TM Modes on Pyramidal Transmission Line Journal Article IEEE Antennas and Wireless Propagation Letters, 13 , pp. 1741 - 1744, 2014. @article{Kim2014b, title = {TM Modes on Pyramidal Transmission Line}, author = {Dohoon Kim and Hyo-J. Eom and Seong-Ook Park }, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06888463.pdf}, doi = {10.1109/LAWP.2014.2352674}, year = {2014}, date = {2014-08-29}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {13}, pages = {1741 - 1744}, abstract = {Transverse magnetic (TM)-mode propagation on a pyramidal transmission line is considered. The mode-matching method is applied to study the TM-mode characteristics. A set of equations for modal coefficients is constituted and numerically solved. Field distributions of the TM modes are presented.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Transverse magnetic (TM)-mode propagation on a pyramidal transmission line is considered. The mode-matching method is applied to study the TM-mode characteristics. A set of equations for modal coefficients is constituted and numerically solved. Field distributions of the TM modes are presented. |
| 115. | Viet-Anh Nguyen; Byeong-Yong Park; Giwan Yoon; Seong-Ook Park A Planar Dipole for Multiband Antenna Systems With Self-Balanced Impedance Journal Article IEEE Antennas and Wireless Propagation Letters, 13 , pp. 1632 - 1635, 2014. @article{Nguyen2014, title = {A Planar Dipole for Multiband Antenna Systems With Self-Balanced Impedance}, author = {Viet-Anh Nguyen and Byeong-Yong Park and Giwan Yoon and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06878461.pdf}, doi = {10.1109/LAWP.2014.2347952}, year = {2014}, date = {2014-08-14}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {13}, pages = {1632 - 1635}, abstract = {In this letter, we present a multiframe L-slot planar dipole loaded with a single microstripline for multiband antenna systems. The multiband is achieved by creating a multiframe L-slot on a host dipole and also by loading the host dipole antenna with a single microstripline to generate a couple of shunts and series of capacitive gaps with an inductive strip, eventually forming LC-like resonators. The antenna supports several wireless communication bands including: LTE bands at 1.7 ~ 1.8 and 2.3 ~ 2.6 GHz; WLAN bands at 2.4 ~ 2.5, 5.2, and 5.8 GHz; WiBro/WiMAX bands at 3 ~ 4 GHz. In addition, to validate the multiband behaviors, we also proposed a simple equivalent circuit for the designed antenna in which biconical transmission lines were adopted to model the host dipole sections. The simulation, fabrication, and measurement of the proposed antenna were implemented. As a result, its reflection coefficients |S11| were found to be better than -7 dB for most operating frequencies along with a sufficiently large bandwidth and good radiation patterns.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this letter, we present a multiframe L-slot planar dipole loaded with a single microstripline for multiband antenna systems. The multiband is achieved by creating a multiframe L-slot on a host dipole and also by loading the host dipole antenna with a single microstripline to generate a couple of shunts and series of capacitive gaps with an inductive strip, eventually forming LC-like resonators. The antenna supports several wireless communication bands including: LTE bands at 1.7 ~ 1.8 and 2.3 ~ 2.6 GHz; WLAN bands at 2.4 ~ 2.5, 5.2, and 5.8 GHz; WiBro/WiMAX bands at 3 ~ 4 GHz. In addition, to validate the multiband behaviors, we also proposed a simple equivalent circuit for the designed antenna in which biconical transmission lines were adopted to model the host dipole sections. The simulation, fabrication, and measurement of the proposed antenna were implemented. As a result, its reflection coefficients |S11| were found to be better than -7 dB for most operating frequencies along with a sufficiently large bandwidth and good radiation patterns. |
| 114. | Byeong-Yong Park; Myung-Hun Jeong; Seong-Ook Park A Magneto-Dielectric Handset Antenna for LTE/WWAN/GPS Applications Journal Article IEEE Antennas and Wireless Propagation Letters, 13 , pp. 1482 - 1485, 2014. @article{Park2014, title = {A Magneto-Dielectric Handset Antenna for LTE/WWAN/GPS Applications}, author = {Byeong-Yong Park and Myung-Hun Jeong and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06866129.pdf}, doi = {10.1109/LAWP.2014.2342256}, year = {2014}, date = {2014-07-25}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {13}, pages = {1482 - 1485}, abstract = {A compact multiband internal antenna covering LTE/GSM/GPS/DCS/PCS/UMTS bands (748-960 and 1575.42-2690 MHz) is presented for mobile terminals. The antenna combines a coupled-fed scheme and a magneto-dielectric material, which has low loss properties (magnetic loss tangent ) up to 3 GHz, thereby achieving not only reduced antenna size but also improved bandwidth. In addition, a T-shaped monopole feeding line generating parasitic capacitance is applied to the proposed antenna. It plays an important role to shift the resonances, especially in the low band. The overall size of the antenna is only 35 ×15 ×4 mm 3 , corresponding to 0.0875λ0 ×0.0375 λ0 ×0.01 λ0 ( λ0 is the wavelength at 750 MHz). The design process and the measured results of the proposed antenna are presented in detail.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A compact multiband internal antenna covering LTE/GSM/GPS/DCS/PCS/UMTS bands (748-960 and 1575.42-2690 MHz) is presented for mobile terminals. The antenna combines a coupled-fed scheme and a magneto-dielectric material, which has low loss properties (magnetic loss tangent ) up to 3 GHz, thereby achieving not only reduced antenna size but also improved bandwidth. In addition, a T-shaped monopole feeding line generating parasitic capacitance is applied to the proposed antenna. It plays an important role to shift the resonances, especially in the low band. The overall size of the antenna is only 35 ×15 ×4 mm 3 , corresponding to 0.0875λ0 ×0.0375 λ0 ×0.01 λ0 ( λ0 is the wavelength at 750 MHz). The design process and the measured results of the proposed antenna are presented in detail. |
| 113. | Byeong-Yong Park; Myung-Hun Jeong; Seong-Ook Park A Miniaturized Microstrip-to-Coplanar-Strip Transition Loaded with Artificial Transmission Lines and 2.4-GHz Antenna Application Journal Article IEEE Antennas and Wireless Propagation Letters, 13 , pp. 1486 - 1489, 2014. @article{Park2014b, title = {A Miniaturized Microstrip-to-Coplanar-Strip Transition Loaded with Artificial Transmission Lines and 2.4-GHz Antenna Application}, author = {Byeong-Yong Park and Myung-Hun Jeong and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06861938.pdf}, doi = {10.1109/LAWP.2014.2341552}, year = {2014}, date = {2014-07-22}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {13 }, pages = {1486 - 1489}, abstract = {A miniaturized microstrip-to-coplanar strip transition and its antenna application are presented in this letter. A composite right/left-handed transmission line and planar artificial transmission lines are used to design the transition in the 2.4-GHz band and to balance the output of the transition over a wider frequency range. In addition, the occupied area of the transition is only 0.087λg 2 . The 3-dB back-to-back insertion loss bandwidth is around 84%. Based on the proposed transition, a quasi-Yagi antenna is demonstrated. The impedance bandwidth is 30.3%. The antenna offers excellent endfire radiation performance. The maximum gain and front-to-back ratio are 5.1 dBi and 21 dB, respectively, at the endfire direction in the operating band. The design process and the measured results of the proposed design are presented in detail.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A miniaturized microstrip-to-coplanar strip transition and its antenna application are presented in this letter. A composite right/left-handed transmission line and planar artificial transmission lines are used to design the transition in the 2.4-GHz band and to balance the output of the transition over a wider frequency range. In addition, the occupied area of the transition is only 0.087λg 2 . The 3-dB back-to-back insertion loss bandwidth is around 84%. Based on the proposed transition, a quasi-Yagi antenna is demonstrated. The impedance bandwidth is 30.3%. The antenna offers excellent endfire radiation performance. The maximum gain and front-to-back ratio are 5.1 dBi and 21 dB, respectively, at the endfire direction in the operating band. The design process and the measured results of the proposed design are presented in detail. |
| 112. | Yun-Taek Im; Maifuz Ali; Seong-Ook Park Slow Modulation Behavior of the FMCW Radar for Wireless Channel Sounding Technology Journal Article IEEE Transactions on Electromagnetic Compatibility, 56 , pp. 1229 - 1237, 2014. @article{Im2014c, title = {Slow Modulation Behavior of the FMCW Radar for Wireless Channel Sounding Technology}, author = {Yun-Taek Im and Maifuz Ali and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06804658.pdf}, doi = {10.1109/TEMC.2014.2311095}, year = {2014}, date = {2014-04-23}, journal = {IEEE Transactions on Electromagnetic Compatibility}, volume = {56}, pages = {1229 - 1237}, abstract = {A frequency-modulated continuous wave (FMCW) radar is used to sounding wireless channel. An intermediate frequency signal of the FMCW radar can be treated simultaneously as a frequency-domain signal as well as a time-domain signal when the modulation time is sufficiently long. This distinctive compatibility enables the FMCW radar system to measure the normalized impulse response for the power delay profile and Rician K-factor by using an oscilloscope. This theory is fully demonstrated and experiments are performed in the reverberation chamber for the small-scale fading environments of Rayleigh and Rician conditions, and all measurements are verified by using the oscilloscope.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A frequency-modulated continuous wave (FMCW) radar is used to sounding wireless channel. An intermediate frequency signal of the FMCW radar can be treated simultaneously as a frequency-domain signal as well as a time-domain signal when the modulation time is sufficiently long. This distinctive compatibility enables the FMCW radar system to measure the normalized impulse response for the power delay profile and Rician K-factor by using an oscilloscope. This theory is fully demonstrated and experiments are performed in the reverberation chamber for the small-scale fading environments of Rayleigh and Rician conditions, and all measurements are verified by using the oscilloscope. |
| 111. | Dong-Hun Shin; Ki-Beom Kim; Jong-Guk Kim; Seong-Ook Park Design of Null-Filling Antenna for Automotive Radar Using the Genetic Algorithm Journal Article IEEE Antennas and Wireless Propagation Letters, 13 , pp. 738 - 741, 2014. @article{Shin2014, title = {Design of Null-Filling Antenna for Automotive Radar Using the Genetic Algorithm}, author = {Dong-Hun Shin and Ki-Beom Kim and Jong-Guk Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06785956.pdf}, doi = {10.1109/LAWP.2014.2316300}, year = {2014}, date = {2014-04-09}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {13}, pages = {738 - 741}, abstract = {A null-filling antenna for automotive radar is investigated using the genetic algorithm. The single column of the proposed antenna consists of four gap-coupled antenna elements and 14 direct-coupled antenna elements. The radiating elements are inclined 45 ° from the feedline. The proposed antenna has 19.67 dBi gain with a -20.19-dB sidelobe level in the elevation and a -25.08-dB sidelobe level in the azimuth direction. The blind zone is reduced from 19.03 to 2.38 m using the proposed antenna for sensing the obstacle. The proposed antenna is a good solution for both short- and long-range automotive radar.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A null-filling antenna for automotive radar is investigated using the genetic algorithm. The single column of the proposed antenna consists of four gap-coupled antenna elements and 14 direct-coupled antenna elements. The radiating elements are inclined 45 ° from the feedline. The proposed antenna has 19.67 dBi gain with a -20.19-dB sidelobe level in the elevation and a -25.08-dB sidelobe level in the azimuth direction. The blind zone is reduced from 19.03 to 2.38 m using the proposed antenna for sensing the obstacle. The proposed antenna is a good solution for both short- and long-range automotive radar. |
| 110. | Myung-Hun Jeong; Byeong-Yong Park; Jung-Hwan Choi; Seong-Ook Park Doppler Spread Spectrum of a Circularly Moving Receiver in an Anechoic and a Reverberation Chamber Journal Article Progress In Electromagnetics Research C, 48 , pp. 125 - 132, 2014. @article{Jeong2014, title = {Doppler Spread Spectrum of a Circularly Moving Receiver in an Anechoic and a Reverberation Chamber}, author = {Myung-Hun Jeong and Byeong-Yong Park and Jung-Hwan Choi and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/13122601.pdf}, doi = {10.2528/PIERC13122601}, year = {2014}, date = {2014-03-18}, journal = {Progress In Electromagnetics Research C}, volume = {48}, pages = {125 - 132}, abstract = {The Doppler phenomena caused by a moving receiver or environmental scatters around a receiver are emulated in an AC(Anechoic Chamber) and a RC(Reverberation Chamber) using platform and mode stirring. In order to verify the emulated Doppler spread spectrum, the measured results in the AC and the RC have been investigated to incorporate Jakes's and 802.11 TGn Doppler models, respectively.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The Doppler phenomena caused by a moving receiver or environmental scatters around a receiver are emulated in an AC(Anechoic Chamber) and a RC(Reverberation Chamber) using platform and mode stirring. In order to verify the emulated Doppler spread spectrum, the measured results in the AC and the RC have been investigated to incorporate Jakes's and 802.11 TGn Doppler models, respectively. |
| 109. | Viet-Anh Nguyen; Rao Shahid Aziz; Seong-Ook Park Multi-band, Dual Polarization, Dual Antennas for Beam Reconfigurable Antenna System for Small Cell Base Station (Invited Paper) Journal Article 2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT), 2014. @article{Nguyen2014c, title = {Multi-band, Dual Polarization, Dual Antennas for Beam Reconfigurable Antenna System for Small Cell Base Station (Invited Paper)}, author = {Viet-Anh Nguyen and Rao Shahid Aziz and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06958625.pdf}, year = {2014}, date = {2014-03-04}, journal = {2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT)}, abstract = {Multiband, dual polarization dual antennas for beam reconfigurable antenna system suitable for small cell indoor wireless base stations is proposed. The whole design consists of horizontal and vertical antennas on a PCB board. Both the antennas are printed monopole type. The antenna supports LTE (1.7-2.1 GHz) and WLAN (2.5 GHz and 5.75 GHz) band frequencies. The simulated reflection coefficients |S 11 | of the proposed antenna shows that at operating frequencies undergo sufficient bandwidth lower than -7dB. Additionally, radiation characteristic of the presented antenna shows dual polarization behavior and switching states of the beam.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Multiband, dual polarization dual antennas for beam reconfigurable antenna system suitable for small cell indoor wireless base stations is proposed. The whole design consists of horizontal and vertical antennas on a PCB board. Both the antennas are printed monopole type. The antenna supports LTE (1.7-2.1 GHz) and WLAN (2.5 GHz and 5.75 GHz) band frequencies. The simulated reflection coefficients |S 11 | of the proposed antenna shows that at operating frequencies undergo sufficient bandwidth lower than -7dB. Additionally, radiation characteristic of the presented antenna shows dual polarization behavior and switching states of the beam. |
| 108. | Dong-Uk Sim; Jung-Ick Moon; Seong-Ook Park An internal triple-band antenna for PCS/IMT-2000/Bluetooth applications Journal Article IEEE Antennas and Wireless Propagation Letters, 3 , 2014. @article{Sim2014b, title = {An internal triple-band antenna for PCS/IMT-2000/Bluetooth applications}, author = {Dong-Uk Sim and Jung-Ick Moon and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/01290930.pdf}, doi = {10.1109/LAWP.2004.827903}, year = {2014}, date = {2014-02-01}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {3}, abstract = {An internal triple-band antenna fed by a microstrip line is proposed for operation in the PCS, IMT-2000, and Bluetooth bands. By using two branches of meander line, the desired resonant frequencies can be achieved. A broadband characteristic for each band is optimized by tuning the parts of the radiating patch and the size of each strip line segment. The proposed antenna and substrate are small enough to be built in a practical mobile handset. Details of the proposed technique and experimental results are presented and discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An internal triple-band antenna fed by a microstrip line is proposed for operation in the PCS, IMT-2000, and Bluetooth bands. By using two branches of meander line, the desired resonant frequencies can be achieved. A broadband characteristic for each band is optimized by tuning the parts of the radiating patch and the size of each strip line segment. The proposed antenna and substrate are small enough to be built in a practical mobile handset. Details of the proposed technique and experimental results are presented and discussed. |
2013 |
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| 107. | Sang-Jin Eom; Ho-Saeng Kim; Maifuz Ali; Seong-Ook Park Embedded Antenna for Metallic Handheld Communication Devices Journal Article Progress In Electromagnetics Research B, 57 , pp. 127 - 138, 2013. @article{Eom2013, title = {Embedded Antenna for Metallic Handheld Communication Devices}, author = {Sang-Jin Eom and Ho-Saeng Kim and Maifuz Ali and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/13101107.pdf}, year = {2013}, date = {2013-12-03}, journal = {Progress In Electromagnetics Research B}, volume = {57}, pages = {127 - 138}, abstract = {In this study, a quad-band folded slot antenna with a monopole feed line embedded in a conductive housing structure (the LCD bracket of a mobile phone) is proposed. The performance of the proposed antenna is evaluated through simulation and measurement, demonstrating that it can provide total radiation efficiencies of more than 40% in the EGSM900, DCS, PCS, and WCDMA1 bands. Over these four bands, the total radiated power (TRP) of a prototype mobile phone using the antenna is 28.5, 27.1, 27.5, and 21 dBm, respectively, while the total isotropic sensitivity (TIS) is 102.7, 104.3, 103.8, and 107.3 dBm, respectively; all of these values satisfy Cellular Telecommunication and Internet Association (CTIA) requirements for over-the-area-(OTA) testing standards. The radiation performance of the proposed antenna in the calling mode is tested and shown to be within satisfactory limits; similarly, the specific absorption rates (SARs) of the prototype mobile phone are also found to be within standard SAR limits.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this study, a quad-band folded slot antenna with a monopole feed line embedded in a conductive housing structure (the LCD bracket of a mobile phone) is proposed. The performance of the proposed antenna is evaluated through simulation and measurement, demonstrating that it can provide total radiation efficiencies of more than 40% in the EGSM900, DCS, PCS, and WCDMA1 bands. Over these four bands, the total radiated power (TRP) of a prototype mobile phone using the antenna is 28.5, 27.1, 27.5, and 21 dBm, respectively, while the total isotropic sensitivity (TIS) is 102.7, 104.3, 103.8, and 107.3 dBm, respectively; all of these values satisfy Cellular Telecommunication and Internet Association (CTIA) requirements for over-the-area-(OTA) testing standards. The radiation performance of the proposed antenna in the calling mode is tested and shown to be within satisfactory limits; similarly, the specific absorption rates (SARs) of the prototype mobile phone are also found to be within standard SAR limits. |
| 106. | Yun-Taek Im; Seong-Ook Park An FMCW and chirp pulse-doppler radar system for surveillance in X-band Journal Article Microwave and Optical Technology Letters, 55 , pp. 474 - 479, 2013. @article{Im2013, title = {An FMCW and chirp pulse-doppler radar system for surveillance in X-band}, author = {Yun-Taek Im and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Im_et_al-2013-Microwave_and_Optical_Technology_Letters.pdf}, doi = {10.1002/mop.27343}, year = {2013}, date = {2013-01-28}, journal = {Microwave and Optical Technology Letters}, volume = {55}, pages = {474 - 479}, abstract = {A narrow band radar system based on a field programmable gate array is proposed for dual‐mode operation.Frequency‐modulated continuous‐wave (FMCW) radar mode is for short‐range target detection and pulse‐Doppler (PD) radar mode is for long‐range target detection. Precomputed codes are used to generate linear frequency modulation signals in both FMCW and PD radar mode. The bandwidths of FMCW and PD radar modes are 10 and 1 MHz. Experiments have been carried out to confirm the system operation. In FMCW radar mode, nonlinear amplitude response can be corrected by precomputed code. In PD radar mode, the RX signals have been checked in the pulse width of 4 μs with a compressed echo signal response.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A narrow band radar system based on a field programmable gate array is proposed for dual‐mode operation.Frequency‐modulated continuous‐wave (FMCW) radar mode is for short‐range target detection and pulse‐Doppler (PD) radar mode is for long‐range target detection. Precomputed codes are used to generate linear frequency modulation signals in both FMCW and PD radar mode. The bandwidths of FMCW and PD radar modes are 10 and 1 MHz. Experiments have been carried out to confirm the system operation. In FMCW radar mode, nonlinear amplitude response can be corrected by precomputed code. In PD radar mode, the RX signals have been checked in the pulse width of 4 μs with a compressed echo signal response. |
2012 |
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| 105. | Han-Cheol Ryu; Seong-Ook Park; Kwang-Yong Kang A spectral analysis of an integrated photomixer/antenna in a homodyne terahertz photomixing system Journal Article Optics Communications, 286 , pp. 363 - 367, 2012. @article{Ryu2012, title = {A spectral analysis of an integrated photomixer/antenna in a homodyne terahertz photomixing system}, author = {Han-Cheol Ryu and Seong-Ook Park and Kwang-Yong Kang}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/1-s2.0-S0030401812009984-main.pdf}, doi = {10.1016/j.optcom.2012.09.021}, year = {2012}, date = {2012-09-28}, journal = {Optics Communications}, volume = {286}, pages = {363 - 367}, abstract = {An analysis has been carried out to estimate the spectral characteristics of an integrated photomixer/antenna in a homodyne photomixing system. The analysis adopts the impedance mismatch factor and Friis power transmission formula used in communication links based on the conventional analysis theory of a terahertz photomixer. The analysis and experimental results have proved that an impedance matching condition between the impedance of a photomixer and the input impedance of an antenna is directly related with photomixing terahertz wave generation. The Friis formula is introduced to calculate the propagation loss of the wave from a transmitter to a receiver in a homodyne photomixing system. A log-periodic antenna was used to ensure a high dynamic range in a broad frequency region. The dynamic range of the homodyne terahertz photomixing system was about 60 dB near 100 GHz and decreased with an increasing frequency from 10 GHz to 1000 GHz. The measured results agree well with the theoretically analyzed results and prove that the terahertz photomixing power is closely related to impedance mismatch factor and it could be estimated in the homodyne terahertz photomixing system without a terahertz power detector.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An analysis has been carried out to estimate the spectral characteristics of an integrated photomixer/antenna in a homodyne photomixing system. The analysis adopts the impedance mismatch factor and Friis power transmission formula used in communication links based on the conventional analysis theory of a terahertz photomixer. The analysis and experimental results have proved that an impedance matching condition between the impedance of a photomixer and the input impedance of an antenna is directly related with photomixing terahertz wave generation. The Friis formula is introduced to calculate the propagation loss of the wave from a transmitter to a receiver in a homodyne photomixing system. A log-periodic antenna was used to ensure a high dynamic range in a broad frequency region. The dynamic range of the homodyne terahertz photomixing system was about 60 dB near 100 GHz and decreased with an increasing frequency from 10 GHz to 1000 GHz. The measured results agree well with the theoretically analyzed results and prove that the terahertz photomixing power is closely related to impedance mismatch factor and it could be estimated in the homodyne terahertz photomixing system without a terahertz power detector. |
| 104. | Manh-Tuan Dao; Dong-Hun Shin; Yun-Taek Im; Seong-Ook Park A two sweeping VCO source for heterodyne FMCW radar Journal Article IEEE Transactions on Instrumentation and measurement, pp. 230 - 239, 2012. @article{Dao2012, title = {A two sweeping VCO source for heterodyne FMCW radar}, author = {Manh-Tuan Dao and Dong-Hun Shin and Yun-Taek Im and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06304920.pdf}, doi = {10.1109/TIM.2012.2212510}, year = {2012}, date = {2012-09-17}, journal = {IEEE Transactions on Instrumentation and measurement}, pages = {230 - 239}, abstract = {We propose and develop a heterodyne frequency modulated continuous wave (FMCW) radar system. The system operates at 14 GHz with a 500-MHz bandwidth in a 100-μs sweeping period, based on two wideband linear RF voltage-controlled oscillator (VCO) sweeping sources, which are controlled by a direct digital synthesizer (DDS) through a phase-locked scheme, leading to a high linearity of the frequency chirping signal. To achieve low phase noise, the RF signals are synthesized from low-noise baseband signals which are generated through a generation scheme of using phase-locked oscillators operating in the 800-MHz frequency range. Additionally, the proposed architecture can eliminate the phase noise contributions and/or frequency deviation due to the uncorrelation of different VCOs. The results are verified through measurements and derivation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We propose and develop a heterodyne frequency modulated continuous wave (FMCW) radar system. The system operates at 14 GHz with a 500-MHz bandwidth in a 100-μs sweeping period, based on two wideband linear RF voltage-controlled oscillator (VCO) sweeping sources, which are controlled by a direct digital synthesizer (DDS) through a phase-locked scheme, leading to a high linearity of the frequency chirping signal. To achieve low phase noise, the RF signals are synthesized from low-noise baseband signals which are generated through a generation scheme of using phase-locked oscillators operating in the 800-MHz frequency range. Additionally, the proposed architecture can eliminate the phase noise contributions and/or frequency deviation due to the uncorrelation of different VCOs. The results are verified through measurements and derivation. |
| 103. | Viet-Anh Nguyen; Myung-Hun Jeong; Manh-Tuan Dao; Seong-Ook Park Four-port Beam Reconfigurable Antenna Array for Pattern Diversity System Journal Article IET Microwaves, Antennas & Propagation, 6 , pp. 1179 - 1186, 2012. @article{Nguyen2012, title = {Four-port Beam Reconfigurable Antenna Array for Pattern Diversity System}, author = {Viet-Anh Nguyen and Myung-Hun Jeong and Manh-Tuan Dao and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06270166.pdf}, doi = {10.1049/iet-map.2011.0606}, year = {2012}, date = {2012-08-20}, journal = {IET Microwaves, Antennas & Propagation}, volume = {6}, pages = {1179 - 1186}, abstract = {This study investigates a practical design for a switched beam planar antenna that can be implemented as a compact, low-cost switchable and/or reconfigurable beam antenna array. The antenna consists of a four-port antenna array, which is based on L-shaped quarter-wavelength slot antenna elements. This type of antenna array is a planar structure and its maximum directional radiation beam pattern presents in an azimuth plane covering 3600. The antenna array operates based on the `ON' or `OFF' states of PIN diodes in each individual slot antenna element and the combined signals from the four-port output. Therefore by properly controlling the state of the PIN diodes, the antenna exposes its characteristics of switchable/ reconfigurable beam patterns in the Φ-plane. To validate the proposed design, a small smart, switched-beam antenna operating at 2.7 GHz in multiple input-multiple output applications is simulated and fabricated.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study investigates a practical design for a switched beam planar antenna that can be implemented as a compact, low-cost switchable and/or reconfigurable beam antenna array. The antenna consists of a four-port antenna array, which is based on L-shaped quarter-wavelength slot antenna elements. This type of antenna array is a planar structure and its maximum directional radiation beam pattern presents in an azimuth plane covering 3600. The antenna array operates based on the `ON' or `OFF' states of PIN diodes in each individual slot antenna element and the combined signals from the four-port output. Therefore by properly controlling the state of the PIN diodes, the antenna exposes its characteristics of switchable/ reconfigurable beam patterns in the Φ-plane. To validate the proposed design, a small smart, switched-beam antenna operating at 2.7 GHz in multiple input-multiple output applications is simulated and fabricated. |
| 102. | Soon-Gyu Yi; Ki-Bok Kong; Byeong-Yong Park; Maifuz Ali; Seong-Ook Park Modeling and Performance Analysis of Reverberation Chamber using FDTD Method Journal Article IET Microwave Antennas and propagation, 6 , pp. 975 - 981, 2012. @article{Yi2012, title = {Modeling and Performance Analysis of Reverberation Chamber using FDTD Method}, author = {Soon-Gyu Yi and Ki-Bok Kong and Byeong-Yong Park and Maifuz Ali and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06248280.pdf}, doi = {10.1049/iet-map.2011.0612}, year = {2012}, date = {2012-07-26}, journal = {IET Microwave Antennas and propagation}, volume = {6}, pages = {975 - 981}, abstract = {A reverberation chamber (RC) is modelled using a finite-difference time-domain (FDTD) method. To evaluate the performance, firstly, the electric field distribution and then the spatial correlation are computed inside the chamber using the FDTD method. In this work, dipole antennas operating at 750 MHz are used in transmitting and receiving mode. Empirical cumulative distribution functions obtained from FDTD simulations and measured S21 are compared with the Rayleigh distribution. The spatial correlation of the electric field inside the RC is computed from the FDTD-simulated and measured results and compared with published correlation functions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A reverberation chamber (RC) is modelled using a finite-difference time-domain (FDTD) method. To evaluate the performance, firstly, the electric field distribution and then the spatial correlation are computed inside the chamber using the FDTD method. In this work, dipole antennas operating at 750 MHz are used in transmitting and receiving mode. Empirical cumulative distribution functions obtained from FDTD simulations and measured S21 are compared with the Rayleigh distribution. The spatial correlation of the electric field inside the RC is computed from the FDTD-simulated and measured results and compared with published correlation functions. |
| 101. | Ki-Bok Kong; Seong-Ook Park Stability and Numerical Dispersion of 3-D Simplified Sampling Biorthogonal ADI Method Journal Article Journal of Electromagnetic Waves and Applications, 24 , pp. 1 - 12, 2012. @article{Kong2012, title = {Stability and Numerical Dispersion of 3-D Simplified Sampling Biorthogonal ADI Method}, author = {Ki-Bok Kong and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Stability.pdf}, doi = {10.1163/156939310790322136}, year = {2012}, date = {2012-04-03}, journal = {Journal of Electromagnetic Waves and Applications}, volume = {24}, pages = {1 - 12}, abstract = {We previously introduced the simplified sampling biorthogonal direction implicit (SSB-ADI) method for 2-D Maxwell's equations. This paper extends it to a 3-D SSB-ADI method. Similar to the original method, the 3-D SSB-ADI method also partially uses the sampling property and compact support of the SBTD algorithm to display spatial discretization. Dispersion and stability analysis are presented. A numerical example shows that the SSB-ADI method is superior to the SB-ADI method in terms of reducing the CPU time and memory requirement of the numerical simulation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We previously introduced the simplified sampling biorthogonal direction implicit (SSB-ADI) method for 2-D Maxwell's equations. This paper extends it to a 3-D SSB-ADI method. Similar to the original method, the 3-D SSB-ADI method also partially uses the sampling property and compact support of the SBTD algorithm to display spatial discretization. Dispersion and stability analysis are presented. A numerical example shows that the SSB-ADI method is superior to the SB-ADI method in terms of reducing the CPU time and memory requirement of the numerical simulation. |
| 100. | Chang-Hee Hyoung; Sung-Weon Kang; Youn-Tae Kim; Seong-Ook Park Transceiver for Human Body Communication Using Frequency Selective Digital Transmission Journal Article ETRI Journal, 34 , pp. 216 - 225, 2012. @article{Hyoung2012, title = {Transceiver for Human Body Communication Using Frequency Selective Digital Transmission}, author = {Chang-Hee Hyoung and Sung-Weon Kang and Youn-Tae Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/etrij.12.0111.0178.pdf}, doi = {10.4218/etrij.12.0111.0178}, year = {2012}, date = {2012-04-01}, journal = {ETRI Journal}, volume = {34}, pages = {216 - 225}, abstract = {This paper presents a transceiver module for human body communications whereby a spread signal with a group of 64 Walsh codes is directly transferred through a human body at a chip rate of 32 Mcps. Frequency selective digital transmission moves the signal spectrum over 5 MHz without continuous frequency modulation and increases the immunity to induced interference by the processing gain. A simple receiver structure with no additional analog circuitry for the transmitter has been developed and has a sensitivity of 250 µVpp. The high sensitivity of the receiver makes it possible to communicate between mobile devices using a human body as the transmission medium. It enables half‐duplex communication of 2 Mbps within an operating range of up to 170 cm between the ultra‐mobile PCs held between fingertips of each hand with a packet error rate of lower than 10−6. The transceiver module consumes 59 mA with a 3.3 V power supply.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper presents a transceiver module for human body communications whereby a spread signal with a group of 64 Walsh codes is directly transferred through a human body at a chip rate of 32 Mcps. Frequency selective digital transmission moves the signal spectrum over 5 MHz without continuous frequency modulation and increases the immunity to induced interference by the processing gain. A simple receiver structure with no additional analog circuitry for the transmitter has been developed and has a sensitivity of 250 µVpp. The high sensitivity of the receiver makes it possible to communicate between mobile devices using a human body as the transmission medium. It enables half‐duplex communication of 2 Mbps within an operating range of up to 170 cm between the ultra‐mobile PCs held between fingertips of each hand with a packet error rate of lower than 10−6. The transceiver module consumes 59 mA with a 3.3 V power supply. |
| 99. | Byung-Chan Kim; Jae-Hoon Yun; Seong-Ook Park Uncertainty Estimation for Evaluating Human Exposure Levels to RF Electromagnetic Fields from Cellular Base Stations Journal Article IEEE Transactions on Electromagnetic Compatibility, 54 , pp. 246 - 253, 2012. @article{Kim2012, title = {Uncertainty Estimation for Evaluating Human Exposure Levels to RF Electromagnetic Fields from Cellular Base Stations}, author = {Byung-Chan Kim and Jae-Hoon Yun and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/06142059-1.pdf}, doi = {10.1109/TEMC.2012.2182768}, year = {2012}, date = {2012-01-31}, journal = {IEEE Transactions on Electromagnetic Compatibility}, volume = {54}, pages = {246 - 253}, abstract = {This paper investigates the estimation of uncertainty when evaluating the levels of human exposure to electromagnetic fields radiated from cellular base stations which aim to verify the exposure compliance with human protection guidelines. Uncertainty should be provided when publishing the results of an evaluation since measured physical quantities are not complete unless they are accompanied by some indication of their reliability. In this study, uncertainty sources are classified into four groups: physical parameters, mechanical constraints, postprocessing, and measurement equipment. Type A standard uncertainties are obtained from repeated observations by in situ measurement around cellular base stations, and they include uncertainties introduced by sources other than measurement equipment. Type B uncertainties are determined from the calibration data offered by measurement equipment manufacturers. The estimated overall uncertainty is ±3.82 dB.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper investigates the estimation of uncertainty when evaluating the levels of human exposure to electromagnetic fields radiated from cellular base stations which aim to verify the exposure compliance with human protection guidelines. Uncertainty should be provided when publishing the results of an evaluation since measured physical quantities are not complete unless they are accompanied by some indication of their reliability. In this study, uncertainty sources are classified into four groups: physical parameters, mechanical constraints, postprocessing, and measurement equipment. Type A standard uncertainties are obtained from repeated observations by in situ measurement around cellular base stations, and they include uncertainties introduced by sources other than measurement equipment. Type B uncertainties are determined from the calibration data offered by measurement equipment manufacturers. The estimated overall uncertainty is ±3.82 dB. |
2011 |
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| 98. | Maifuz Ali; Seong-Ook Park Analysis of Horn Antenna in Receiving Mode as an EM Field Sensor Journal Article International Journal of Antennas and Propagation, 2012 , 2011. @article{Ali2011, title = {Analysis of Horn Antenna in Receiving Mode as an EM Field Sensor}, author = {Maifuz Ali and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/11119.pdf}, year = {2011}, date = {2011-11-09}, journal = {International Journal of Antennas and Propagation}, volume = {2012}, abstract = {Electromagnetic (EM) field measurement uses antenna in receiving mode as EM field sensor (EMFS). FDTD technique is applied to analyze the horn antenna in this mode. The performances of horn antenna as EMFS are predicted in terms of antenna factor (AF), and the results are compared with measurements. New empirical formula for quick calculation of antenna factor of pyramidal horn is also presented. Also, the gain of horn antennas are computed in receiving mode using FDTD technique, and the results are compared with published measured result and far-field gain formula.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Electromagnetic (EM) field measurement uses antenna in receiving mode as EM field sensor (EMFS). FDTD technique is applied to analyze the horn antenna in this mode. The performances of horn antenna as EMFS are predicted in terms of antenna factor (AF), and the results are compared with measurements. New empirical formula for quick calculation of antenna factor of pyramidal horn is also presented. Also, the gain of horn antennas are computed in receiving mode using FDTD technique, and the results are compared with published measured result and far-field gain formula. |
| 97. | Manh-Tuan Dao; Viet-Anh Nguyen; Yun-Taek Im; Seong-Ook Park; Giwan Yoon 3D Polarized Channel Modeling and Performance Comparison of MIMO Antenna Configurations With Different Polarizations Journal Article IEEE Transactions on Antennas and Propagation, 59 , pp. 2672 - 2682, 2011. @article{Dao2011, title = {3D Polarized Channel Modeling and Performance Comparison of MIMO Antenna Configurations With Different Polarizations}, author = {Manh-Tuan Dao and Viet-Anh Nguyen and Yun-Taek Im and Seong-Ook Park and Giwan Yoon}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/05765442.pdf}, doi = {10.1109/TAP.2011.2152319}, year = {2011}, date = {2011-05-10}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {59}, pages = {2672 - 2682}, abstract = {We propose a three-dimensional (3D) polarized MIMO channel model, which takes into account 3D power angular spectrum and comprehensive propagation characteristics of electromagnetic waves excited by polarized antennas. Based on the model, we derive a close form expression of the spatial correlation as a function of the physical parameters representing both characteristics of arbitrary antennas and propagation environment in 3D space. The spatial correlation expression allows to use the Von Mises Fisher (VMF) distribution, resulting in a more accurate and general channel model. Through simulation, we evaluate and compare performance, in terms of the spatial correlation and capacity, of 2 × 2 MIMO configurations with different polarizations, i.e., V/V, V/H, and slanted ±45° polarizations, as a function of critical input parameters including elevation angle, antenna orientation, antenna spacing, cross-polarization discrimination (XPD), and signal-to-noise ratio (SNR). The effect of the parameters on the performance is analyzed, and verified in certain cases through the literature.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We propose a three-dimensional (3D) polarized MIMO channel model, which takes into account 3D power angular spectrum and comprehensive propagation characteristics of electromagnetic waves excited by polarized antennas. Based on the model, we derive a close form expression of the spatial correlation as a function of the physical parameters representing both characteristics of arbitrary antennas and propagation environment in 3D space. The spatial correlation expression allows to use the Von Mises Fisher (VMF) distribution, resulting in a more accurate and general channel model. Through simulation, we evaluate and compare performance, in terms of the spatial correlation and capacity, of 2 × 2 MIMO configurations with different polarizations, i.e., V/V, V/H, and slanted ±45° polarizations, as a function of critical input parameters including elevation angle, antenna orientation, antenna spacing, cross-polarization discrimination (XPD), and signal-to-noise ratio (SNR). The effect of the parameters on the performance is analyzed, and verified in certain cases through the literature. |
| 96. | Maifuz Ali; Seong-Ook Park Analysis of horn Radiation Pattern Using Utd Edge and Corner Diffraction Journal Article Progress In Electromagnetics Research M, 17 (87 - 99), 2011. @article{Ali2011b, title = {Analysis of horn Radiation Pattern Using Utd Edge and Corner Diffraction}, author = {Maifuz Ali and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/070122106.pdf}, year = {2011}, date = {2011-02-23}, journal = {Progress In Electromagnetics Research M}, volume = {17}, number = {87 - 99}, abstract = {Finite edge geometrical theory of diffraction (FEGTD) approach is a new and latest improvement in GTD technique. This FEGTD technique is applied to the H-plane and E-plane horn radiation problems with spherical source excitation. The horn patterns obtained with the FEGTD approach are found to be in good agreement with measured results.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Finite edge geometrical theory of diffraction (FEGTD) approach is a new and latest improvement in GTD technique. This FEGTD technique is applied to the H-plane and E-plane horn radiation problems with spherical source excitation. The horn patterns obtained with the FEGTD approach are found to be in good agreement with measured results. |
| 95. | Byeong-Yong Park; Jung-Hwan Choi; Seong-Ook Park Design of a Decoupled MIMO Antenna for LTE Application Journal Article Microwave and Optical Technology Letters, 53 , 2011. @article{Park2011, title = {Design of a Decoupled MIMO Antenna for LTE Application}, author = {Byeong-Yong Park and Jung-Hwan Choi and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Park_et_al-2011-Microwave_and_Optical_Technology_Letters.pdf}, doi = {10.1002/mop.25766}, year = {2011}, date = {2011-01-19}, journal = {Microwave and Optical Technology Letters}, volume = {53}, abstract = {A compact multiple‐input‐multiple‐output antenna array at 700 MHz has been proposed for long‐term evolution‐standardized handsets. A simple shunt element‐based decoupling technique has been used to realize high isolation between the strongly coupled antenna elements. The antennas with and without decoupling have been evaluated for envelope correlation coefficient, radiation efficiency, and channel capacity characteristics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A compact multiple‐input‐multiple‐output antenna array at 700 MHz has been proposed for long‐term evolution‐standardized handsets. A simple shunt element‐based decoupling technique has been used to realize high isolation between the strongly coupled antenna elements. The antennas with and without decoupling have been evaluated for envelope correlation coefficient, radiation efficiency, and channel capacity characteristics. |
2010 |
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| 94. | Han-Cheol Ryu; Su-Jae Lee; Seung-Eon Moon; Min-Hwan Kwak; Mun-Cheol Paek; Kwang-Yong Kang; Seong-Ook Park A Phased Array Antenna Using Ferroelectric CPW Phase Shifter Active Modules Journal Article Ferroelectrics, 407 , pp. 45 - 53, 2010. @article{Ryu2010, title = {A Phased Array Antenna Using Ferroelectric CPW Phase Shifter Active Modules}, author = {Han-Cheol Ryu and Su-Jae Lee and Seung-Eon Moon and Min-Hwan Kwak and Mun-Cheol Paek and Kwang-Yong Kang and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/paau.pdf}, doi = {10.1080/00150193.2010.484707}, year = {2010}, date = {2010-12-01}, journal = {Ferroelectrics}, volume = {407}, pages = {45 - 53}, abstract = {A phased array antenna using ferroelectric coplanar waveguide (CPW) phase shifter active modules is presented based on a Ba0.6Sr0.4TiO3 (BST) thin film. The ferroelectric BST thin film was deposited on an MgO substrate by using pulsed laser deposition. The active module amplifies an RF signal with low noise and changes the phase of a received RF signal to control the main beam of the array antenna. It is composed of low noise amplifier (LNA), dc block, and ferroelectric CPW phase shifter. The prototype of 6×12 phased array patch antenna with the active modules using a ferroelectric phase shifter is proposed. The proposed array antenna continuously scanned its main beam in elevation plane to 32° from its broadside direction at 11.85 GHz by applying the continuous dc voltage to the ferroelectric phase shifter.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A phased array antenna using ferroelectric coplanar waveguide (CPW) phase shifter active modules is presented based on a Ba0.6Sr0.4TiO3 (BST) thin film. The ferroelectric BST thin film was deposited on an MgO substrate by using pulsed laser deposition. The active module amplifies an RF signal with low noise and changes the phase of a received RF signal to control the main beam of the array antenna. It is composed of low noise amplifier (LNA), dc block, and ferroelectric CPW phase shifter. The prototype of 6×12 phased array patch antenna with the active modules using a ferroelectric phase shifter is proposed. The proposed array antenna continuously scanned its main beam in elevation plane to 32° from its broadside direction at 11.85 GHz by applying the continuous dc voltage to the ferroelectric phase shifter. |
| 93. | Yong-Sun Shin; Seong-Ook Park A Monopole antenna with a Magneto-Dielectric Material and its MIMO application for 700MHz-LTE-band diversity in MIMO array Journal Article Microwave and Optical Technology Letters, 2010. @article{Shin2010, title = {A Monopole antenna with a Magneto-Dielectric Material and its MIMO application for 700MHz-LTE-band diversity in MIMO array}, author = {Yong-Sun Shin and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/103.pdf}, doi = {10.1002/mop.25470}, year = {2010}, date = {2010-10-01}, journal = {Microwave and Optical Technology Letters}, abstract = {This article presents an antenna with a magneto-dielectric material and its MIMO application for LTE-band.The proposed antenna is a folded monopole type and occupies a compact volume of 7.5 × 18.5 × 3.4 mm3. For reducing the size, obtaining the broad bandwidth, and enhancing the isolation performance, the magneto-dielectric material is applied as a supporter. The parameters of the magneto-dielectric material are ε′ − jε″= 3.29−j0.09 and μ′ − jμ″ = 2.01−j0.38 at 780 MHz. For evaluations of the MIMO application, the antenna has been measured in reverberation chamber. The Microwave Studio (MWS) is employed for optimizing the design parameters, and the simulated results are well agreed with those of the measured one.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This article presents an antenna with a magneto-dielectric material and its MIMO application for LTE-band.The proposed antenna is a folded monopole type and occupies a compact volume of 7.5 × 18.5 × 3.4 mm3. For reducing the size, obtaining the broad bandwidth, and enhancing the isolation performance, the magneto-dielectric material is applied as a supporter. The parameters of the magneto-dielectric material are ε′ − jε″= 3.29−j0.09 and μ′ − jμ″ = 2.01−j0.38 at 780 MHz. For evaluations of the MIMO application, the antenna has been measured in reverberation chamber. The Microwave Studio (MWS) is employed for optimizing the design parameters, and the simulated results are well agreed with those of the measured one. |
| 92. | Byung-Chan Kim; Seong-Ook Park Evaluation of RF Electromagnetic Field Exposure Levels from Cellular Base Stations in Korea Journal Article Forthcoming Bioelectromagnetics, 31 , pp. 495 - 498, Forthcoming. @article{Kim2010c, title = {Evaluation of RF Electromagnetic Field Exposure Levels from Cellular Base Stations in Korea}, author = {Byung-Chan Kim and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Kim_et_al-2010-Bioelectromagnetics.pdf}, doi = {10.1002/bem.20585}, year = {2010}, date = {2010-09-30}, journal = {Bioelectromagnetics}, volume = {31}, pages = {495 - 498}, abstract = {This article presents the measurement results of human exposure to CDMA800 and CDMA1800 signals at locations in Korea where the general public has expressed concern. Measurements were performed at 50 locations across the country to compare the electromagnetic field levels with the general public exposure compliance limits. At each site, the distances between the nearest single or co-located base station and measurement positions were within a range of approximately 32-422 m. The measured exposure levels were very low compared with the international standard and the Korean human protection notice. The highest field level was 1.5 V/m, which corresponds to 0.15% of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for human exposure.}, keywords = {}, pubstate = {forthcoming}, tppubtype = {article} } This article presents the measurement results of human exposure to CDMA800 and CDMA1800 signals at locations in Korea where the general public has expressed concern. Measurements were performed at 50 locations across the country to compare the electromagnetic field levels with the general public exposure compliance limits. At each site, the distances between the nearest single or co-located base station and measurement positions were within a range of approximately 32-422 m. The measured exposure levels were very low compared with the international standard and the Korean human protection notice. The highest field level was 1.5 V/m, which corresponds to 0.15% of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for human exposure. |
| 91. | Han-Cheol Ryu; Min-Hwan Kwak; Seung-Beom Kang; Se-Young Jeong; Min-Cheol Paek; Kwang-Yong Kang; Seong-Ook Park A Dielectric Property Analysis of Ferroelectric Thin Film Using Terahertz Time-Domain Spectroscopy Journal Article Integrated Ferroelectrics, 95 , pp. 83 - 91, 2010. @article{Ryu2010b, title = {A Dielectric Property Analysis of Ferroelectric Thin Film Using Terahertz Time-Domain Spectroscopy}, author = {Han-Cheol Ryu and Min-Hwan Kwak and Seung-Beom Kang and Se-Young Jeong and Min-Cheol Paek and Kwang-Yong Kang and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/di.pdf}, doi = {10.1080/10584580701756573}, year = {2010}, date = {2010-09-20}, journal = {Integrated Ferroelectrics}, volume = {95}, pages = {83 - 91}, abstract = {This paper presents complex dielectric properties of ferroelectric BSTO thin film, deposited on MgO substrate by pulsed laser deposition, in the frequency range of 0.5 ∼ 3.0 THz using terahertz time-domain spectroscopy (THz-TDS). In order to extract complex dielectric properties of the thin film, multiple reflections within the thin film were considered and an error function between the calculated and measured data was introduced. The real part of the dielectric constant of the BSTO thin film was less than 170 and the dielectric loss tangent of the BSTO thin film varied between 0.9 and 3.0. All values of an error function were less than 7 × 10− 4 in the measured frequency ranges. The analysis method using THz-TDS enables us to find out complex dielectric properties of ferroelectric thin film exactly.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper presents complex dielectric properties of ferroelectric BSTO thin film, deposited on MgO substrate by pulsed laser deposition, in the frequency range of 0.5 ∼ 3.0 THz using terahertz time-domain spectroscopy (THz-TDS). In order to extract complex dielectric properties of the thin film, multiple reflections within the thin film were considered and an error function between the calculated and measured data was introduced. The real part of the dielectric constant of the BSTO thin film was less than 170 and the dielectric loss tangent of the BSTO thin film varied between 0.9 and 3.0. All values of an error function were less than 7 × 10− 4 in the measured frequency ranges. The analysis method using THz-TDS enables us to find out complex dielectric properties of ferroelectric thin film exactly. |
| 90. | Yun-Taek Im; Jee-Hoon Lee; Yong-Woo Jeong; Sang-Ik Lee; Seong-Ook Park A Beam-Switchable Coupled Feeding Network in X-band Journal Article Microwave and Optical Technology Letters, 52 , pp. 1865 - 1868, 2010. @article{Im2010e, title = {A Beam-Switchable Coupled Feeding Network in X-band}, author = {Yun-Taek Im and Jee-Hoon Lee and Yong-Woo Jeong and Sang-Ik Lee and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/25313.pdf}, doi = {10.1002/mop.25313}, year = {2010}, date = {2010-08-01}, journal = {Microwave and Optical Technology Letters}, volume = {52}, pages = {1865 - 1868}, abstract = {An antenna feeding network is proposed for a driving system. It consists of branch line couplers, Wilkinson power dividers, and asymmetric delay lines. Using an orthogonal beam property and an antenna sharing technique, its radiation patterns are measured at 10 GHz. The measured beam coverage angle was 70º in the five input ports by using eight radiating elements}, keywords = {}, pubstate = {published}, tppubtype = {article} } An antenna feeding network is proposed for a driving system. It consists of branch line couplers, Wilkinson power dividers, and asymmetric delay lines. Using an orthogonal beam property and an antenna sharing technique, its radiation patterns are measured at 10 GHz. The measured beam coverage angle was 70º in the five input ports by using eight radiating elements |
| 89. | Byoung-Nam Kim; Seong-Ook Park; Jung-Keun Oh Broadband Built-In Antenna with New Enclosed 3D Coupling Feed Structure Journal Article Microwave and Optical Technology Letters, 52 , pp. 2306 - 2309, 2010. @article{Kim2010, title = {Broadband Built-In Antenna with New Enclosed 3D Coupling Feed Structure}, author = {Byoung-Nam Kim and Seong-Ook Park and Jung-Keun Oh}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Kim_et_al-2010-Microwave_and_Optical_Technology_Letters.pdf}, doi = {10.1002/mop.25441}, year = {2010}, date = {2010-07-14}, journal = {Microwave and Optical Technology Letters}, volume = {52}, pages = {2306 - 2309}, abstract = {Wideband built‐in antenna with an enclosed 3D coupling feed structure for wireless terminals is presented.With the proposed design scheme, a nine‐band built‐in antenna that covers GSM850/GSM900/GPS/DCS1800/PCS1900/WCDMA/WiBro2350/Bluetooth/WiMax 2500 is experimentally tested. This novel nine‐band built‐in handset antenna is developed within the limits of a 40 × 17.5 × 6 mm3 volume, achieving good agreement between measurement and simulation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Wideband built‐in antenna with an enclosed 3D coupling feed structure for wireless terminals is presented.With the proposed design scheme, a nine‐band built‐in antenna that covers GSM850/GSM900/GPS/DCS1800/PCS1900/WCDMA/WiBro2350/Bluetooth/WiMax 2500 is experimentally tested. This novel nine‐band built‐in handset antenna is developed within the limits of a 40 × 17.5 × 6 mm3 volume, achieving good agreement between measurement and simulation. |
| 88. | Ki-Bok Kong; Seong-Ook Park Unconditionally Stable LOD-FDTD Method based on the Simplified Sampling Bi-orthogonal Algorithm Journal Article Microwave and Optical Technology Letters, 52 , pp. 2183 - 2185, 2010. @article{Kong2010, title = {Unconditionally Stable LOD-FDTD Method based on the Simplified Sampling Bi-orthogonal Algorithm}, author = {Ki-Bok Kong and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Kong_et_al-2010-Microwave_and_Optical_Technology_Letters-1.pdf}, doi = {10.1002/mop.25461}, year = {2010}, date = {2010-07-14}, journal = {Microwave and Optical Technology Letters}, volume = {52}, pages = {2183 - 2185}, abstract = {This letter presents an unconditionally stable locally one‐dimensional (LOD) finite‐difference time‐domain method based on the simplified sampling biorthogonal algorithm (SSB‐LOD). The suggested approach requires fewer arithmetic operations than in the SSB‐ADI scheme. This leads to a reduction of CPU time relative to the SSB‐ADI method while equivalent numerical accuracy is retained. The numerical implementation of two parallel conducting plate shows that the CPU time of the SSB‐LOD has been reduced to approximately 85% of that of the SSB‐ADI.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This letter presents an unconditionally stable locally one‐dimensional (LOD) finite‐difference time‐domain method based on the simplified sampling biorthogonal algorithm (SSB‐LOD). The suggested approach requires fewer arithmetic operations than in the SSB‐ADI scheme. This leads to a reduction of CPU time relative to the SSB‐ADI method while equivalent numerical accuracy is retained. The numerical implementation of two parallel conducting plate shows that the CPU time of the SSB‐LOD has been reduced to approximately 85% of that of the SSB‐ADI. |
| 87. | Byung-Chan Kim; Seong-Ook Park Reduction of Averaging Time for Evaluation of Human Exposure to Radio frequency Electromagnetic Fields from Cellular Base Stations Journal Article IEICE Transactions on Communications, E93.B , pp. 1862 - 1864, 2010. @article{Kim2010b, title = {Reduction of Averaging Time for Evaluation of Human Exposure to Radio frequency Electromagnetic Fields from Cellular Base Stations}, author = {Byung-Chan Kim and Seong-Ook Park}, doi = {10.1587/transcom.E93.B.1862}, year = {2010}, date = {2010-07-01}, journal = {IEICE Transactions on Communications}, volume = {E93.B}, pages = {1862 - 1864}, abstract = {In order to determine exposure compliance with the electromagnetic fields from a base station's antenna in the far-field region, we should calculate the spatially averaged field value in a defined space. This value is calculated based on the measured value obtained at several points within the restricted space. According to the ICNIRP guidelines, at each point in the space, the reference levels are averaged over any 6min (from 100kHz to 10GHz) for the general public. Therefore, the more points we use, the longer the measurement time becomes. For practical application, it is very advantageous to spend less time for measurement. In this paper, we analyzed the difference of average values between 6min and lesser periods and compared it with the standard uncertainty for measurement drift. Based on the standard deviation from the 6min averaging value, the proposed minimum averaging time is 1min.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In order to determine exposure compliance with the electromagnetic fields from a base station's antenna in the far-field region, we should calculate the spatially averaged field value in a defined space. This value is calculated based on the measured value obtained at several points within the restricted space. According to the ICNIRP guidelines, at each point in the space, the reference levels are averaged over any 6min (from 100kHz to 10GHz) for the general public. Therefore, the more points we use, the longer the measurement time becomes. For practical application, it is very advantageous to spend less time for measurement. In this paper, we analyzed the difference of average values between 6min and lesser periods and compared it with the standard uncertainty for measurement drift. Based on the standard deviation from the 6min averaging value, the proposed minimum averaging time is 1min. |
| 86. | Jung-Hwan Choi; Seong-Ook Park Generation of Rayleigh/Rician Fading Channels With Variable RMS Delay by Changing Boundary Conditions of the Reverberation Chamber Journal Article IEEE Antennas and Wireless Propagation Letters, 9 , pp. 510 - 513, 2010. @article{Choi2010c, title = {Generation of Rayleigh/Rician Fading Channels With Variable RMS Delay by Changing Boundary Conditions of the Reverberation Chamber}, author = {Jung-Hwan Choi and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/05473103.pdf}, doi = {10.1109/LAWP.2010.2051400}, year = {2010}, date = {2010-05-27}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {9}, pages = {510 - 513}, abstract = {This letter presents the properties of the generated Rayleigh/Rician fading channels in the reverberation chamber (RC) experimentally. Radio propagation channels that undergo multipath fading phenomena can be characterized by power delay profiles (PDPs), delay spreads, and statistical distributions of the received power. The RC under the conventional configuration for electromagnetic compatibility/electromagnetic interference (EMC/EMI) evaluations has Rayleigh distribution because there are no direct paths between the TX and RX antennas. Most of the transmitted signals arrive at the RX part through multiple reflection paths. By changing the boundary conditions and the position of the TX antenna, Rayleigh/Rician fading channels with variable root-mean-square (RMS) delay spread can be generated in the RC considering K-factor simultaneously.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This letter presents the properties of the generated Rayleigh/Rician fading channels in the reverberation chamber (RC) experimentally. Radio propagation channels that undergo multipath fading phenomena can be characterized by power delay profiles (PDPs), delay spreads, and statistical distributions of the received power. The RC under the conventional configuration for electromagnetic compatibility/electromagnetic interference (EMC/EMI) evaluations has Rayleigh distribution because there are no direct paths between the TX and RX antennas. Most of the transmitted signals arrive at the RX part through multiple reflection paths. By changing the boundary conditions and the position of the TX antenna, Rayleigh/Rician fading channels with variable root-mean-square (RMS) delay spread can be generated in the RC considering K-factor simultaneously. |
| 85. | Yun-Taek Im; Jee-Hoon Lee; Yong-Woo Jeong; Sang-Ik Lee; Seong-Ook Park A Polarization Selective Series-Fed Array Antenna Journal Article Microwave and Optical Technology Letters, 52 , pp. 1861 - 1864, 2010. @article{Im2010d, title = {A Polarization Selective Series-Fed Array Antenna}, author = {Yun-Taek Im and Jee-Hoon Lee and Yong-Woo Jeong and Sang-Ik Lee and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/Im_et_al-2010-Microwave_and_Optical_Technology_Letters.pdf}, doi = {10.1002/mop.25323}, year = {2010}, date = {2010-05-18}, journal = {Microwave and Optical Technology Letters}, volume = {52}, pages = {1861 - 1864}, abstract = {A series‐fed elliptically polarized array antenna is proposed for X‐band systems. Symmetrical series feeding at the array antenna center and truncated patches are applied to reduce side lobe levels (SLL) by modeling the array factor. A series‐fed elliptically polarized array antenna is proposed for X‐band systems. Symmetrical series feeding at the array antenna center and truncated patches are applied to reduce SLLs by modeling the array factor. The measured gain is 24.8 dBic and the axial ratio is between 3 and 6 dB. The SLLs are −19.0 and −16.2 dB in the zx and yz plane, respectively.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A series‐fed elliptically polarized array antenna is proposed for X‐band systems. Symmetrical series feeding at the array antenna center and truncated patches are applied to reduce side lobe levels (SLL) by modeling the array factor. A series‐fed elliptically polarized array antenna is proposed for X‐band systems. Symmetrical series feeding at the array antenna center and truncated patches are applied to reduce SLLs by modeling the array factor. The measured gain is 24.8 dBic and the axial ratio is between 3 and 6 dB. The SLLs are −19.0 and −16.2 dB in the zx and yz plane, respectively. |
| 84. | Jung-Hwan Choi; Jee-Hoon Lee; Seong-Ook Park Characterizing the Impact of Moving Mode-Stirrers on the Doppler Spread Spectrum in a Reverberation Chamber Journal Article IEEE Antennas and Wireless Propagation Letters, 9 , pp. 375 - 378, 2010. @article{Choi2010b, title = {Characterizing the Impact of Moving Mode-Stirrers on the Doppler Spread Spectrum in a Reverberation Chamber}, author = {Jung-Hwan Choi and Jee-Hoon Lee and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/05456176.pdf}, doi = {10.1109/LAWP.2010.2049331}, year = {2010}, date = {2010-04-29}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {9}, pages = {375 - 378}, abstract = {A moving mode-stirrer in a reverberation chamber (RC) not only changes the field distributions within the reverberation chamber, but also causes a Doppler effect. In this letter, the Doppler spread spectrum of a received signal in a reverberation chamber is characterized according to the radius and rotational velocity of the mode-stirrers and TX antenna positions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A moving mode-stirrer in a reverberation chamber (RC) not only changes the field distributions within the reverberation chamber, but also causes a Doppler effect. In this letter, the Doppler spread spectrum of a received signal in a reverberation chamber is characterized according to the radius and rotational velocity of the mode-stirrers and TX antenna positions. |
| 83. | Jung-Hwan Choi; Seong-Ook Park Exact Evaluation of Channel Capacity Difference of MIMO Handset Antenna Arrays Journal Article IEEE Antennas and Wireless Propagation Letters, 9 (219 - 222), 2010. @article{Choi2010, title = {Exact Evaluation of Channel Capacity Difference of MIMO Handset Antenna Arrays}, author = {Jung-Hwan Choi and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/05439981.pdf}, doi = {10.1109/LAWP.2010.2046710}, year = {2010}, date = {2010-03-29}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {9}, number = {219 - 222}, abstract = {This letter presents the exact evaluation of the channel capacity difference of different 2 × 2 multiple-input-multiple-output (MIMO) handset antenna configurations. In order to investigate the performance enhancement of a MIMO antenna system, the channel capacity is estimated in a reverberation chamber with the normalized channel matrix measured using a network analyzer under the conventional configuration for electromagnetic compatibility/electromagnetic interference (EMC/EMI) evaluations. However, performance comparison of different antenna configurations at the same signal-to-noise ratio (SNR) is not an exact evaluation in the same propagation environment because the received power is obviously different. We propose the evaluation method for exact performance comparisons and drive the exact representation of the channel capacity difference of MIMO handset antenna arrays in a reverberation chamber. The estimated results using the proposed method are compared to the channel capacity evaluated at the same SNR for validation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This letter presents the exact evaluation of the channel capacity difference of different 2 × 2 multiple-input-multiple-output (MIMO) handset antenna configurations. In order to investigate the performance enhancement of a MIMO antenna system, the channel capacity is estimated in a reverberation chamber with the normalized channel matrix measured using a network analyzer under the conventional configuration for electromagnetic compatibility/electromagnetic interference (EMC/EMI) evaluations. However, performance comparison of different antenna configurations at the same signal-to-noise ratio (SNR) is not an exact evaluation in the same propagation environment because the received power is obviously different. We propose the evaluation method for exact performance comparisons and drive the exact representation of the channel capacity difference of MIMO handset antenna arrays in a reverberation chamber. The estimated results using the proposed method are compared to the channel capacity evaluated at the same SNR for validation. |
| 82. | Rashid Ahmad Bhatti; Soon-Gyu Yi; Seong-Ook Park Compact Antenna Array With Port Decoupling for LTE-Standardized Mobile Phones Journal Article IEEE Antennas and Wireless Propagation Letters, 8 , pp. 1430 - 1433, 2010. @article{Bhatti2010, title = {Compact Antenna Array With Port Decoupling for LTE-Standardized Mobile Phones}, author = {Rashid Ahmad Bhatti and Soon-Gyu Yi and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/05382565.pdf}, doi = {0.1109/LAWP.2010.2040677}, year = {2010}, date = {2010-01-15}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {8}, pages = {1430 - 1433}, abstract = {A compact dual-element antenna has been designed at 710 MHz for newly emerging long-term evolution (LTE) personal wireless communication standard applications. The proposed antenna consists of two printed meander-line monopoles with edge-to-edge separation of nearly ¿/45. The antenna elements are printed on FR-4 substrate and are located at the top edge of the ground plane measuring 50 × 87 mm2. An LC-components-based branchline hybrid coupler is used to decouple the antenna elements. The prototype antenna has been evaluated through the scattering parameters, radiation patterns, envelope cross correlation, and the channel capacity measurements. Isolation between the ports is better than 35 dB with matched ports at 710 MHz. The antenna offers reasonable multiple-input-multiple-output (MIMO) performances that make it suitable for LTE-standardized mobile phones.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A compact dual-element antenna has been designed at 710 MHz for newly emerging long-term evolution (LTE) personal wireless communication standard applications. The proposed antenna consists of two printed meander-line monopoles with edge-to-edge separation of nearly ¿/45. The antenna elements are printed on FR-4 substrate and are located at the top edge of the ground plane measuring 50 × 87 mm2. An LC-components-based branchline hybrid coupler is used to decouple the antenna elements. The prototype antenna has been evaluated through the scattering parameters, radiation patterns, envelope cross correlation, and the channel capacity measurements. Isolation between the ports is better than 35 dB with matched ports at 710 MHz. The antenna offers reasonable multiple-input-multiple-output (MIMO) performances that make it suitable for LTE-standardized mobile phones. |
2009 |
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| 81. | Ki-Bok Kong; Seong-Ook Park Analysis of Simplified SB-ADI Scheme for Two-Dimensional Maxwell’s Equations Journal Article IEEE Antennas and Wireless Propagation Letters, 8 , pp. 1002 - 1005, 2009. @article{Kong2009, title = {Analysis of Simplified SB-ADI Scheme for Two-Dimensional Maxwell’s Equations}, author = {Ki-Bok Kong and Seong-Ook Park}, url = {http://143.248.148.42/wordpress/wp-content/uploads/2018/10/05184859.pdf}, doi = {10.1109/LAWP.2009.2028663}, year = {2009}, date = {2009-07-31}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {8}, pages = {1002 - 1005}, abstract = {This letter represents a simplified sampling biorthogonal alternating-direction implicit (SSB-ADI) method based on the sampling biorthogonal time domain (SBTD) algorithm. Two sampling functions with different orders for sampling biorthogonal method are used to display spatial discretization. Dispersion and stability analyses are presented. It is shown through a numerical simulation that SSB-ADI reduced the CPU time and memory compared to the SB-ADI method.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This letter represents a simplified sampling biorthogonal alternating-direction implicit (SSB-ADI) method based on the sampling biorthogonal time domain (SBTD) algorithm. Two sampling functions with different orders for sampling biorthogonal method are used to display spatial discretization. Dispersion and stability analyses are presented. It is shown through a numerical simulation that SSB-ADI reduced the CPU time and memory compared to the SB-ADI method. |