{"title":"Design of a Dual-Mode Waveguide CP Antenna with a Symmetric Beamwidth Using Short Stub for Low-Orbit Satellite TC&R","authors":"Dong-Su Choi, Yoon-Seon Choi, Hyo-Jin Lee, Sun-Ik Lee, Jong-Myung Woo","doi":"10.26866/jees.2023.5.r.183","DOIUrl":"https://doi.org/10.26866/jees.2023.5.r.183","url":null,"abstract":"In this study, a dual-mode waveguide circularly polarized antenna for TC&R (telemetry, command, and ranging) was proposed for the communication between a low-orbit satellite and a ground station. The proposed antenna required both a wide -10 dB bandwidth and axial ratio bandwidth of 7.1–7.3 GHz and 8.0–8.4 GHz. The antenna was designed with a stepped septum inside a square waveguide to obtain circular polarization and the axial ratio wide bandwidth. Next, a dual-mode synthesis method was adopted for link budgeting by combining square and circular waveguides. The requirement was that the co-polarization level with a symmetric -3 dB beamwidth of 39° must be -5 dBic or higher at ±76.5°, and the cross-polarization level must average -15 dBic or lower at ±76.5°. Finally, the corrugate structure attached to the outside of the extended circular waveguide was offset in multiple steps to suppress the back lobe of the crosspolarization As a result, the axial ratio maintained an average of 1.8 dB at 0° within each band of the required frequency. In addition, the co-polarization obtained an average of -4.52 dBic in the 7.2 GHz band and -5.31 dBic in the 8.2 GHz band at ±76.5°. Finally, in the case of the cross-polarization pattern, the back lobe level was suppressed by 9.89 dB at 7.2 GHz by the corrugate structure, and an average value of -19.9 dBic or less was obtained at ±76.5°. The proposed antenna was confirmed to be effective as a Korean low-orbit satellite TC&R antenna with a radiation pattern of a symmetric beamwidth.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135039502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Novel Multi-Band Substrate-Integrated Waveguide Antenna and Extension to a Deca-Band Antenna","authors":"Youngje Sung","doi":"10.26866/jees.2023.5.l.17","DOIUrl":"https://doi.org/10.26866/jees.2023.5.l.17","url":null,"abstract":"In this letter, a deca-band substrate-integrated waveguide (SIW) antenna with filtering function is proposed. The number of slots was increased from 4 to 10, and the quad-band antenna design is extended to a deca-band antenna. At this time, good impedance matching characteristics are maintained without changing other parameters except the patch length. The fabricated deca-band antenna has 10 resonances between 3–4.4 GHz and a broadside radiation pattern characteristic at each resonance frequency, and the measured gain is 1.8–4.2 dBi.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135039940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chaewon Jung, Youngkeun Yoo, Hyun-Woo Kim, Hyun-Chool Shin
{"title":"Detecting Sleep-Related Breathing Disorders Using FMCW Radar","authors":"Chaewon Jung, Youngkeun Yoo, Hyun-Woo Kim, Hyun-Chool Shin","doi":"10.26866/jees.2023.5.r.189","DOIUrl":"https://doi.org/10.26866/jees.2023.5.r.189","url":null,"abstract":"Polysomnography (PSG) is currently the sole method for detecting breathing disorders that occur during sleep, such as apnea and hypopnea. However, PSG monitoring is quite inconvenient for test subjects. This study proposes a non-contact method for detecting sleep-related breathing disorders that uses frequency-modulated continuous wave (FMCW) radar. The proposed method effectively extracts respiratory signals from radar signals and uses the degree of reduction in the amplitude of the respiratory signals and the duration of the reduction interval as data to detect breathing disorder intervals. The experimental results show that the respiratory signals extracted using the proposed method are similar to the actual respiratory signals. Furthermore, the breathing disorder intervals detected during sleep using FMCW radar are consistent with the actual apnea and hypopnea intervals as confirmed by the PSG results. These results demonstrate that the proposed method is suitable for non-contact detection of breathing disorders during sleep using FMCW radar.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135040073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Dakhli, J.M. Floc’h, M. Aseeri, A. Mersani, H. Rmili
{"title":"Design of Compact and Superdirective Metamaterial-Inspired Two- and Three-Elements Antenna Arrays","authors":"S. Dakhli, J.M. Floc’h, M. Aseeri, A. Mersani, H. Rmili","doi":"10.26866/jees.2023.4.r.179","DOIUrl":"https://doi.org/10.26866/jees.2023.4.r.179","url":null,"abstract":"This paper presents the development of a miniature antenna array in a small space in order to achieve superdirectivity for long-range communication. The proposed structures consist of a superdirective metamaterial-inspired array based on a capacitively loaded loop (CLL) driven by an electrically small monopole antenna. This elementary antenna is then used in two- and three-array configurations separated by a fixed interelement distance of 0.1λ to achieve a higher directivity and compact size (with λ the wavelength calculated at the operation frequency 1.850 GHz). The design of the elementary antenna, its simulated radiation performances, as well as those of the parasitic array are also reported. The results of the optimization of two- and three-antenna arrays are discussed. For this study, three corresponding prototypes were fabricated and tested. The measured impedance mismatch and radiation pattern results are presented and shown to be in good agreement with their simulated values. The maximum measured directivity is equal to 5.9 dBi and 4.75 dBi in the case of the two- and three- elements, respectively. The proposed antenna arrays can serve for the realization of point-to-point wireless links and can have a significant impact on compact and high-directive radiofrequency front-ends of a wireless system and for wireless power transfer applications.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44281407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hong‐Sun Yoon, Min Park, J. Yook, Dongsu Kim, Youngcheol Park
{"title":"Compact Asymmetrical Quasi-MMIC Doherty Power Amplifier","authors":"Hong‐Sun Yoon, Min Park, J. Yook, Dongsu Kim, Youngcheol Park","doi":"10.26866/jees.2023.4.l.15","DOIUrl":"https://doi.org/10.26866/jees.2023.4.l.15","url":null,"abstract":"This paper presents a compact asymmetrical Doherty power amplifier (PA) based on a quasi-MMIC configuration for 5G sub-6 GHz applications. The proposed Doherty PA is composed of commercial GaN HEMTs and several passive components implemented on a silicon (Si) substrate. In order to achieve size and cost advantages, passive components such as a power divider, input matching networks, output matching networks, and a Doherty combiner are realized using Si-integrated passive device (Si-IPD) technology, which costs about 40% of the budget for the entire GaN MMIC process. For the 3.5 GHz pulsed-continuous waveform signal, the fabricated Doherty PA has an efficiency of 52.6% at a saturated output power of 44.2 dBm. Furthermore, an efficiency of 45.6% was achieved with the output power back-off (OBO) of 7.0 dB. The implemented PA occupies only 8.9 mm × 5.6 mm.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45645815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Youna Jang, Cha Hye Seong, T. Kang, Sang‐Min Han, D. Ahn
{"title":"A New Doherty Combiner with Wide Bandwidth for Magnitude and Phase Balance Compensation","authors":"Youna Jang, Cha Hye Seong, T. Kang, Sang‐Min Han, D. Ahn","doi":"10.26866/jees.2023.4.r.178","DOIUrl":"https://doi.org/10.26866/jees.2023.4.r.178","url":null,"abstract":"This paper proposes a novel Doherty combiner that uses a series and parallel resonant circuit for wideband. Unlike conventional combiners, the aim of the proposed combiners is to extend bandwidth for not only the magnitude bandwidth, but also phase balance by employing series and parallel resonant circuits at the output impedance of the peaking amplifier. Considering the load impedance of the peaking amplifier, the Doherty combiners were analyzed in the theory of this study by deriving the series and parallel resonant circuit values. The output phase balances are determined for the targeted bandwidth to achieve uniform phase balance in the proposed combiner I using a series resonator. For better magnitude bandwidth, the slope of reflection coefficient (Γ) at port 3 in the combiner II using series resonator was derived using the derivative of Γ with respect to ω. Experimental results show that the proposed combiner I has 63.5% magnitude fractional bandwidth (FBW) and 118% FBW with the phase balance at ±2.5°. The proposed combiner II also has 85% magnitude FBW and 118% FBW with the phase balance at ±2.5°.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42466369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Directional Monopole Antenna Using a Planar Lossy Magnetic (PLM) Surface","authors":"Jae‐Gon Lee","doi":"10.26866/jees.2023.4.r.177","DOIUrl":"https://doi.org/10.26866/jees.2023.4.r.177","url":null,"abstract":"A directional monopole antenna using a planar lossy magnetic (PLM) surface is proposed in this paper. When a monopole antenna is designed vertically on the ground plane composed of a perfect electric conductor (PEC) and a perfect magnetic conductor (PMC), the surface current on the ground plane cannot flow on the PMC and only flows in one direction on the PEC. Therefore, the electromagnetic (EM) wave of such a monopole antenna can radiate in the direction perpendicular to the ground. Alternatively, a PLM surface such as a ferrite sheet with a high relative permeability was employed to achieve EM properties similar to the PMC. To verify the feasibility of the proposed antenna, a ferrite sheet with a relative permeability of 20 and a magnetic loss tangent of 10 at 2 GHz was utilized to implement the half PMC ground plane, and the monopole antenna was bent for miniaturization. The measured peak gain and the -10 dB bandwidth was about 1.3 dBi and 23% at the resonant frequency, respectively.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43651393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Implementation Possibilities of Standard Site Method Sub-cases for EMC Antenna Calibrations in Non-ideal Site Conditions","authors":"İlkcan Coşkun, S. Ikizoglu","doi":"10.26866/jees.2023.4.r.180","DOIUrl":"https://doi.org/10.26866/jees.2023.4.r.180","url":null,"abstract":"Today, a number of engineering issues require electromagnetic compatibility (EMC) tests, in turn triggering the need for EMC-antenna calibrations. In this framework, experimenters seek accurate and time-saving solutions. Basically, standard site method (SSM) ANSI C63.5-2006 stipulates the near-to-ideal conditions on an empty and vast land, where three antennas are used for antenna factor determination. In our previous work, we investigated the suitability of narrow test sites for antenna calibration according to three-antenna SSM-ANSIC-63.5-2006, whose usability was validated under certain conditions. In the present study, we expand our research by applying the sub-cases of using a known antenna and identical antennas specified in the standard in order to shorten the calibration process. The results reveal that the methods for various calibrations are useful for successfully running the process even in non-ideal sites and help significantly reduce the experimentation time, considering the uncertainty limits specified in EMC test standards.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43011294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Compact Low-Loss Reflection-Type Harmonic Transponder for Battery-Less RFID Sensors Based on Harmonic Backscattering","authors":"Daju Lee, Juntaek Oh","doi":"10.26866/jees.2023.5.r.182","DOIUrl":"https://doi.org/10.26866/jees.2023.5.r.182","url":null,"abstract":"This study presents a compact reflection-type harmonic transponder with a wide input power range for battery-less radio frequency identification (RFID) sensors based on harmonic backscattering. Miniaturizing the circuit size of conventional harmonic transponders is difficult because the input and output matching stages are configured separately, and two antennas are used for each port. The proposed harmonic transponder based on a dual-band matching network matches the load simultaneously at the fundamental and second harmonic frequencies over a wide input power range, thus enhancing the conversion gain (CG) with a compact size. For verification, the proposed transponder is implemented in a compact size with dimensions of 19 mm × 17.8 mm. The measured CG of the implemented transponder is maintained at over −10 dB in the wide input power range of −6.4 dBm to 10.6 dBm at 2.45 GHz. Th e harmonic transponder is configured with a dual-band chip antenna and measured in free space to verify whether it is suitable for battery-less RFID sensors. The measured detectable effective distance to the proposed circuit is 6.3 m in free space, with an equivalent isotropically radiated power of 42.6 dBm.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48022955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Efficient Clutter Cancellation Algorithm Based on a Suppressed Clutter Map for FMCW Radar Systems","authors":"Bong-seok Kim, Youngseok Jin, Jieun Bae, E. Hyun","doi":"10.26866/jees.2023.5.l.16","DOIUrl":"https://doi.org/10.26866/jees.2023.5.l.16","url":null,"abstract":"This paper proposes an efficient clutter cancellation algorithm based on suppressed clutter map for frequency-modulated continuous wave radar systems. In conventional clutter cancellation algorithms based on clutter maps, range-Doppler maps are employed. However, if the radar cross section (RCS) of the targets is significantly lower than the RCS of the clutter, a problem may occur in that the targets may also be removed in the clutter-removal process. To solve this problem, the proposed algorithm creates a range-Doppler map to which the moving target indicator (MTI) algorithm is applied instead of the general range-Doppler map that does not include the MTI algorithm. The range-Doppler map, used after applying the clutter suppression filter, significantly reduces the clutter removal effect on targets in which RCS is relatively weak by suppressing the effect of relatively dominant clutter signals. The experimental results showed that the proposed algorithm detects weak targets that remain undetected by the existing map-based clutter-removal algorithm.","PeriodicalId":15662,"journal":{"name":"Journal of electromagnetic engineering and science","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41695401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}