Microwave and Optical Technology Letters最新文献

{"title":"A Five-Branch Wideband 3-dB Coupler Based on Substrate Integrated Gap Waveguide","authors":"Jingchao Sheng,&nbsp;Hang Yi,&nbsp;Peilun Su,&nbsp;Yuyang Mao,&nbsp;Hao Wu,&nbsp;Ying Zhu,&nbsp;Yifan Yang,&nbsp;Cheng Guo,&nbsp;Anxue Zhang,&nbsp;Qian Yang","doi":"10.1002/mop.70131","DOIUrl":"https://doi.org/10.1002/mop.70131","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper proposed a SIGW wideband 3-dB coupler that operates mainly in the Ka-band by combining the SIGW theory and the theory of branch-line coupler. Firstly, the structure of the SIGW is analyzed. Then, the coupler is designed using the SIGW transmission line with five-branch to realize a wideband. Finally, the proposed SIGW coupler is fabricated and measured, and the measurement results are consistent with the simulation results. The SIGW coupler centered at 30 GHz has a 40% wide bandwidth (24–36 GHz). The return loss of the coupler is better than 10 dB and the isolation is better than 17 dB. The SIGW coupler in this paper has a wide operating bandwidth, high isolation, and is easy to fabricate compared to conventional branch-line couplers.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 3","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 and Continuously Tunable 360° Phase Shifter Using Cascaded Transformer-Based 180° Reflection-Type and Switched-Type Phase-Shift-Cell","authors":"Jia-Yang Pu,&nbsp;Jin Xu,&nbsp;Jia-Hao Su,&nbsp;Ming Zhao,&nbsp;Fang Liu","doi":"10.1002/mop.70128","DOIUrl":"https://doi.org/10.1002/mop.70128","url":null,"abstract":"<div>\u0000 \u0000 <p>This article presents a design method for compact and continuously tunable 360° phase shifter (PS). The proposed structure consists of a 180° reflection-type phase shifter (RTPS) cascaded with a 180° switched-type phase shifter (STPS). RTPS consists of a transformer-based 90° coupler and Γ-π reflection loads. STPS consists of a transformer and a single-pole double-throw (SPDT). For experimental verification, a compact and continuously tunable 360° PS with a center frequency of 1.5 GHz was designed and fabricated. From the measurement results, the proposed 360° PS provides a tunable phase shift range (PSR) of 0°–360°, with an the insertion loss (IL) of 2.85 ± 0.7 dB, which has a circuit size of 0.031 λg².</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143466163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design Method of Power Chip Terminations With Lower Cost, Lower Voltage Standing Wave Ratio, and Broader Bandwidth","authors":"Hao Peng,&nbsp;Na Xue,&nbsp;Ziyan Qi,&nbsp;Lifeng Chen,&nbsp;Jiming Chen,&nbsp;Yu Liu,&nbsp;Serioja Ovidiu Tatu,&nbsp;Tao Yang,&nbsp;Jiadong Pan,&nbsp;Feng Zhang","doi":"10.1002/mop.70133","DOIUrl":"https://doi.org/10.1002/mop.70133","url":null,"abstract":"<div>\u0000 \u0000 <p>In this paper, we deeply explore a design method for power chip terminations with low-cost, low VSWR and broadband performance. Through a comprehensive investigation of existing power chip terminations, the electromagnetic leakage significantly impacts its performance. To address these issues, an electromagnetic constraint boundary has been introduced to enhance its VSWR. Considering the high cost of the gold plating process on the sides of chemical vapor deposition diamond substrates, an independent electromagnetic constraint metal carrier with a concave shape is proposed. TaN thin film is employed as the terminal matching load. Simulation results reveal that the VSWR of different substrates (ceramic and diamond substrates) are very similar. Consequently, this work presents a design, simulation, and measurement of a power chip termination applied to a ceramic substrate. Measurement results demonstrate that the VSWR is less than 1.5 over a frequency range of DC to 43.5 GHz, significantly outperforming existing commercial power chip terminations. In addition, the fluctuation of VSWR across the broadband operating frequencies has been discussed in detail.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143466164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"28 GHz Circular Polarized MIMO Antenna System With Polarization Diversity for Millimeter-Wave Applications","authors":"Asmaa E. Farahat,&nbsp;Khalid. F. A. Hussein,&nbsp;Rania R. Elsharkawy","doi":"10.1002/mop.70137","DOIUrl":"https://doi.org/10.1002/mop.70137","url":null,"abstract":"<div>\u0000 \u0000 <p>A four-port dual circularly polarized (CP) MIMO antenna system is proposed for millimeter-wave (mm-wave) applications, especially 5G mobile communications. The MIMO antenna system is constructed from a compact-size CP antenna designed at 28 GHz. The CP antenna has some defects in the ground plane that have the effect of increasing the operating bandwidth and improving the axial ratio. The antenna patch and the defected ground are symmetric about the 45° line to ensure good circular polarization. A microstrip line divided into three sections is used to feed the antenna. The feed line sections are used to match the input impedance to 50 Ω at 28 GHz. The design evolution is described starting with a square patch, which is modified through the design phases to reach the final radiating patch. Numerical simulations of the single-element CP antenna are performed using the CST microwave studio simulator to ensure the antenna performance at 28 GHz regarding the circular polarization, impedance matching, and radiation pattern. MIMO system is constructed using four elements of the designed CP antenna. Two of the antennas produce right-hand circular polarized waves, and the other two produce left-hand circular polarized waves. The proposed MIMO configuration is appropriate to satisfy the polarization diversity scheme. A practical model for the single and MIMO antenna is fabricated and subjected to experimental verification through measurements. A good consent is found between the numerical results and the experimental measurements for both the single antenna and the MIMO system. The CP antenna in the proposed MIMO system has a return loss of less than<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mspace></mspace>\u0000 \u0000 <mo>−</mo>\u0000 \u0000 <mn>20</mn>\u0000 <mspace></mspace>\u0000 \u0000 <mtext>dB</mtext>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $,-20,text{dB}$</annotation>\u0000 </semantics></math> and an axial ratio of less than <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>0.4</mn>\u0000 <mspace></mspace>\u0000 \u0000 <mtext>dB</mtext>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $0.4,text{dB}$</annotation>\u0000 </semantics></math>. Finally, a comparison between the proposed CP antenna and MIMO system with similar designs found in the literature is performed.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143455804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wide Stopband Bandpass Filter With Higher-Order Mode Suppression","authors":"Ruofeng Xu,&nbsp;Wei Tang,&nbsp;Yinfang Xu,&nbsp;Xianglin Kong,&nbsp;Jun Wang,&nbsp;Lei Zhao","doi":"10.1002/mop.70147","DOIUrl":"https://doi.org/10.1002/mop.70147","url":null,"abstract":"<div>\u0000 \u0000 <p>To meet the requirement of band selection performance and low loss in wireless communication system, a wide stopband bandpass filter with higher-order mode suppression is proposed in this paper. The filter utilizes the high-pass characteristic of the Half Mode Substrate Integrated Waveguide (HMSIW) to produce a lower stop-band. A quarter-wavelength resonator is used to generate a transmission zero at the upper band. Thus, the bandpass effect is realized from 3.4 to 5.6 GHz. The 3 dB relative bandwidth reaches 46.7%, the in-band insertion loss is less than 0.7 dB, and the return loss is better than −15 dB. The transverse slots of the resonant part cut the surface current flow and effectively suppress the higher-order TE mode; the additional metal vias near the electric wall are equivalent to the inductors for storing magnetic energy, which reduce the harmonic interference of higher-order TM modes. The −25dB stopband of the filter is from 6.5 to 17 GHz, thus a wide stopband of 3.7 times of center frequency is realized. The measured results are well matched with simulated ones. The filter has the characteristics of simple structure, low profile, low loss, and easy fabrication, which provides a novel concept for the design of high-performance filtering devices in radar and aerospace systems.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143439255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Development of Dual Polarized Conjugate Matched Feed for Satellite Communications","authors":"Raksha Ram,&nbsp;Ranajit Dey,&nbsp;Vijay Kumar Singh,&nbsp;Sanjeev Kulshrestha,&nbsp;Milind B. Mahajan","doi":"10.1002/mop.70127","DOIUrl":"https://doi.org/10.1002/mop.70127","url":null,"abstract":"<div>\u0000 \u0000 <p>Conjugate matched feed supresses secondary cross-pol of offset reflector by utilizing higher order mode (TE₂₁) along with fundamental mode (TE₁₁) in a circular feed itself. In this paper, physically realizable stable co-axial structure of TE₂₁ mode coupler and co-axial horn were designed and tested for dual polarization applications. The procedure for designing of co-axial horn for maintaining phase difference between the modes is also discussed. The secondary pattern of the matched feed with offset reflector having F/D of 0.7 and 45° offset angle for dual linear polarization was analyzed using physical optics (PO) in GRASP (Ticra tool). The observation revealed 7 dB improvement in the secondary cross-polar performance for both polarizations using matched feed as compared to TE₁₁ feed over 7.8% bandwidth. The primary measurement of the feed alone was carried out in an anechoic chamber, and the measured primary pattern was compared with the simulated value. The designed feed could be an alternative of dual reflector antenna used in satellite communications.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-Layer Reflectarray Providing Broadband Linear-to-Circular Polarization Conversion","authors":"Samara Gharbieh,&nbsp;Renaud Loison,&nbsp;Akil Jrad,&nbsp;Ali Harmouch,&nbsp;María García-Vigueras","doi":"10.1002/mop.70144","DOIUrl":"https://doi.org/10.1002/mop.70144","url":null,"abstract":"<p>This paper introduces a single-layer reflectarray (RA) design capable of converting incoming linearly polarized waves into outgoing circularly polarized ones while focusing the beam. The design employs nonresonant unit cells, extending the classical concept of meander-line polarizers. These new unit cells enable a 360° phase range while maintaining a 90° phase difference between the two orthogonal components of the reflected field. The RA, based on this concept, is designed, manufactured, and measured, achieving a 38.2% bandwidth with an axial ratio below 2 dB.</p>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mop.70144","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Miniaturized Wideband Single-Layer CP Metasurface Antenna Using CPW-Fed","authors":"Zuxue Xia,&nbsp;Xin Xiong,&nbsp;Wenhai Xia,&nbsp;Xin Cao,&nbsp;Jiayuan Hu,&nbsp;Rui Cheng","doi":"10.1002/mop.70141","DOIUrl":"https://doi.org/10.1002/mop.70141","url":null,"abstract":"<div>\u0000 \u0000 <p>A novel miniaturized wideband single-layer circularly polarized metasurface antenna using coplanar waveguide (CPW)-fed and hybrid metasurface is proposed. To miniaturize the metasurface antenna, a hybrid embedded metasurface structure composed of multiple slotted rectangles and small rectangles is introduced. By embedding the metallic patches, additional capacitance is introduced in the gaps, which lowers the resonance frequency of the metasurface and significantly reduces its size. Circularly polarized radiation is realized as the inclined CPW feeder excites the degenerate modes of the hybrid metasurface, which exhibit a 90° phase difference. In conclusion, the metasurface antenna is fabricated and measured to confirm the validity of the design. The antenna has a compact radiation aperture of 0.39<i>λ</i>₀ × 0.49<i>λ</i>₀ (center frequency of 5.82 GHz), a wider 3 dB AR bandwidth of 17.1% (5.31 ~ 6.30 GHz), and a wider impedance bandwidth of 24.8% (4.93 ~ 6.33 GHz), with a peak gain of 7.7 dBic.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-Line Bandpass Filters With Flexible Transmission Zero Distribution Using Asymmetric Dual-Behavior Resonators","authors":"Lunyong Xiao,&nbsp;Lan Cheng,&nbsp;Yifan Kong,&nbsp;Yuxing He","doi":"10.1002/mop.70146","DOIUrl":"https://doi.org/10.1002/mop.70146","url":null,"abstract":"<div>\u0000 \u0000 <p>We propose in this letter an analytical method for realizing bandpass filters with <i>N</i> reflection zeros (RZs) but more than <i>N</i> transmission zeros (TZs) that are flexibly (symmetrically or asymmetrically) positioned outside the passband. The approach relies on the development of asymmetric dual-behavior resonators at lowpass domain, accommodating one reflection zero (RZ) and two asymmetric TZs. These asymmetric DBRs are then properly adopted into an in-line prototype, allowing them to be cascaded with conventional resonators via constant or frequency-variant couplings. To provide a planar solution, we also introduce practical distributed models of the asymmetric DBRs where all elements are properly determined to meet the required in-band and out-of-band performances. For validation, an experimental example is carried out with microstrip implementation, along with reasonable responses.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fully Planar Endfire Circularly Polarized Antenna of Substrate Integrated Waveguide Loaded With Planar Bending Dipole","authors":"Yifan Yin,&nbsp;Jin He,&nbsp;Feiyu Ge,&nbsp;Shuo Bao,&nbsp;Shunli Li,&nbsp;Ke Wu","doi":"10.1002/mop.70152","DOIUrl":"https://doi.org/10.1002/mop.70152","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper proposes a fully planar endfire circularly polarized (CP) antenna on a single-layer substrate, consisting of a substrate-integrated waveguide (SIW) loaded with a bending dipole. The SIW horn, which can be directly integrated with RF circuits, could generate high-gain vertically polarized (VP) radiation. The novel bending dipole is actually a traveling-wave helical dipole radiator and could generate high-gain horizontally polarized (HP) radiation. The bending dipole is fed by the SIW horn with a tapered parallel stripline. The mechanism and design method of the proposed antenna is presented, and its experimental prototype has been designed and measured. The measured impedance bandwidth of −10 dB covers a bandwidth of 2.4 GHz from 25.3 to 27.7 GHz, the 3-dB axial ratio (AR) bandwidth is 2.4 GHz from 24.9 to 27.3 GHz, and the effective bandwidth is from 25.3 to 27.3 GHz. The measured CP gain is over 7.3 dBic and the peak gain is 9.1 dBic in the effective bandwidth. The high gain planar endfire CP antenna has a compact size of only 3.06<i>λ</i>₀*1.2<i>λ</i>₀*0.13<i>λ</i>₀.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 2","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}