Microwave and Optical Technology Letters最新文献

{"title":"Balanced Dual-Band Bandpass Filter With Intrinsic Common-Mode Suppression Using Coplanar Stripline and Asymmetrical Coplanar Stripline","authors":"Xuehui Guan,&nbsp;Shiwen Xiong,&nbsp;Baoping Ren,&nbsp;Yiheng Zhang","doi":"10.1002/mop.70339","DOIUrl":"https://doi.org/10.1002/mop.70339","url":null,"abstract":"<div>\u0000 \u0000 <p>In this letter, a balanced dual-band bandpass filter with intrinsic common-mode suppression is proposed based on coplanar stripline and asymmetrical coplanar stripline. The proposed balanced dual-band bandpass filter is composed of a four-mode resonator, where two pairs of resonant modes form two two-pole passbands with adjustable passband locations. The four-mode resonator consists of two coupled hybrid coplanar stripline and asymmetrical coplanar stripline open-loop resonators. Four resonant modes of the proposed resonator can be independently controlled by adjusting the parameters of coplanar stripline and asymmetrical coplanar stripline sections. To validate the proposed structure and design method, a balanced dual-band bandpass filter working at 1.8 and 2.4 GHz was designed, fabricated, and measured. The measured results are in good agreement with the simulated ones, thus strongly demonstrating the feasibility of achieving a balanced dual-band bandpass filter with common mode suppression.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858617","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 Monolithic InGaP/GaAs HBT Front-End Architecture for Continuous-Wave Doppler Radar Sensors in Omnidirectional Moving Target Detection","authors":"Kai Yi,&nbsp;Min Lan,&nbsp;Yuwu Liu,&nbsp;Huihua Liu","doi":"10.1002/mop.70362","DOIUrl":"https://doi.org/10.1002/mop.70362","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper proposes a cost-effective Doppler radar front-end architecture based on InGaP/GaAs heterojunction bipolar transistor (HBT) technology for continuous-wave (CW) omnidirectional moving target detection. The compact front-end architecture integrates three core components—a mixer, a power divider, and an oscillator—on a monolithic microwave integrated circuit (MMIC). The power divider (PD) provides both the transmit signal and the local oscillator (LO) signal for the mixer. The oscillator employs a conventional cross-coupled configuration, achieving a phase noise of −119.5 dBc/Hz at 1 MHz offset from the carrier frequency of 5.81 GHz. The compact transceiver achieves an area of 0.5 × 0.55 mm² while maintaining greater than 18 dB conversion gain over the entire 5.725–5.875 GHz ISM band. The total power consumption is less than 33 mW with a 3.3 V supply. Experimental measurements on two DRS testing systems demonstrated that the system's transmission power was approximately −2 dBm, and omnidirectional moving human presence detection tests indicated a horizontal detection distance greater than 4 meters when the radar system was mounted at a height of 3 meters.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861892","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":"Dual-Channel SPR Sensor Based on an Elliptical-Core Double-Hollow Fiber With Subwavelength Gratings","authors":"Zhiguo Xiu,&nbsp;Fengjun Tian,&nbsp;Sichen Liu,&nbsp;Xinghua Yang,&nbsp;Wenzhuo Zhao,&nbsp;Wenlong Ge,&nbsp;Li Li,&nbsp;Chao Liu","doi":"10.1002/mop.70331","DOIUrl":"https://doi.org/10.1002/mop.70331","url":null,"abstract":"<div>\u0000 \u0000 <p>A dual-channel surface plasmon resonance (SPR) sensor is proposed, based on an elliptical-core double-hollow fiber that integrates subwavelength gratings (SWGs). By etching a microstructure with subwavelength periodicity on the outer wall of the fiber and depositing a metal layer, the coupling efficiency between the guided light and the metal interface can be significantly enhanced. We first demonstrate a subwavelength SPR sensor employing single-mode fiber and photonic crystal fiber, each showing several-fold improvement in performance. Furthermore, by extending this design to a dual-channel SPR sensor, simulations indicate that the refractive index (RI) sensitivity can exceed 15 000 nm/RIU in dual-channel detection, while also enabling temperature measurement with a temperature sensitivity of approximately −5 nm/°C. Compared with traditional single-channel fiber SPR sensors, the proposed structure not only offers higher sensitivity but also supports multi-parameter detection. Owing to its unique design, the design effectively reduces coupling between the two channels, thereby maintaining low channel crosstalk even under high-sensitivity conditions. This study introduces an innovative design for high-sensitivity, multi-parameter SPR fiber sensors. Broadening the application of SWGs in fiber sensing.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858611","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":"W-Band High-Efficiency Low-Profile Four-Folded Transmitarray Antenna Based on Dual-Phase Compensation Strategy","authors":"Xianhui He,&nbsp;Lu Cong,&nbsp;Yongzheng Li,&nbsp;Quan Xue,&nbsp;Wanchen Yang","doi":"10.1002/mop.70361","DOIUrl":"https://doi.org/10.1002/mop.70361","url":null,"abstract":"<div>\u0000 \u0000 <p>A novel high-efficiency low-profile four-folded transmitarray antenna (FTA) is proposed. The FTA is composed of a dual-functional transmit-reflected array (TRA) and a polarized conversion surface (PCS) based on single-layer PCB. The work proposed a novel dual-functional transmit-reflected element and dual-phase compensation strategy. Firstly, dual-functional transmit-reflected element is composed of double pairs of U-shaped and cross-shaped patches to realize efficient transmission and reflection, with the losses under 2 dB. Thus, high-efficiency dual-functional transmit-reflected array can be achieved. Secondly, dual-phase compensation strategy for primary and secondary arrays is put forward to realize low profile folding configuration, which is capable of achieving a profile compression ratio of no more than 0.25. Different from conventional FTA designs, no polarized grids, metal vias or bonding layers are required. For demonstration, one FTA prototype working in W-band is designed, fabricated and measured. The total size of the FTA is about 60 × 60 × 15.75 mm³. The measured peak gain and aperture efficiencies are 28.68 dBi and 21.38% at 89 GHz with 3-dB gain bandwidth of 10%, which achieved the highest gain and aperture efficiency in current W-band research. Benefiting from high-efficiency, low-profile, single-layer fabrication, as well as easy integration, the proposed FTA is expected to be a competitive candidate for vehicle radar and LEO satellites communication systems in high frequency of millimeter wave band to terahertz band.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858619","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":"Fast Solve of Broadband Electromagnetic Scattering Problems Based on Krylov Subspace Basis Functions Combining With Compressive Sensing","authors":"Zhonggen Wang,&nbsp;Haoran Yuan,&nbsp;Yufa Sun,&nbsp;Wenyan Nie","doi":"10.1002/mop.70350","DOIUrl":"https://doi.org/10.1002/mop.70350","url":null,"abstract":"<div>\u0000 \u0000 <p>While using the Krylov subspace basis functions (KSBFs) method to analyze the broadband electromagnetic scattering problem, a large amount of time is required to recalculate the KSBFs at each frequency point. To address this issue, this paper proposes an ultra-wideband KSBFs (UKSBFs) method integrated with compressive sensing. The UKSBFs, derived through Arnoldi iterative computation and partial orthogonalization at the highest frequency point within the range of interest, serve as the sparse basis. A few rows from the impedance matrix and excitation vector are extracted to form the measurement matrix and measurements, constructing a compressive sensing framework for the efficient solution of the induced current. Benefiting from only the UKSBFs of the highest frequency points need to be calculated and efficient recovery algorithm, the method significantly reduces the radar cross section time for computing broadband targets. Finally, the numerical results demonstrate the computational efficiency and accuracy of the method.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858621","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":"Wideband Circularly Polarized Elliptical Patch Antenna and Array Designs","authors":"Peng Guo,&nbsp;Xianzheng Zong","doi":"10.1002/mop.70342","DOIUrl":"https://doi.org/10.1002/mop.70342","url":null,"abstract":"<div>\u0000 \u0000 <p>A broadband circularly polarized (CP) 2 × 2 antenna array using elliptical patch antenna elements is designed in this study. The antenna element is composed of four elliptical patches, four metal posts, and a stair-shaped slot. By rotating the elliptical patches and modifying the coupling slot as stair-shaped, a CP magnetoelectric dipole (ME-dipole) antenna is first realized. Moreover, another two elliptical patches are introduced to generate extra CP mode, which enhances the axial-ratio (AR) bandwidth. The designed CP elliptical patch antenna is expanded to a 2 × 2 antenna array which a feeding network using sequential rotation technology is adopted to feed the array. Measured results indicate that the antenna array exhibits an impedance bandwidth (|S₁₁| &lt; −10 dB) of 67.6% and a 3 dB AR bandwidth of 59.1% is obtained. Besides, the measured peak gain is 14.14 dBic at the center frequency 5.5 GHz. The excellent performances make it suitable for C-band communication systems which CP radiation is required.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858620","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 Wideband and Vertically Polarized Flush-Mounted Antenna With High Horizontal Gain Using Distributed Dielectric Loading","authors":"Weikun Tian,&nbsp;Zhenkai Zhou,&nbsp;Zongliang Zheng","doi":"10.1002/mop.70358","DOIUrl":"https://doi.org/10.1002/mop.70358","url":null,"abstract":"<div>\u0000 \u0000 <p>This letter presents a wideband, vertically-polarized, and omnidirectional antenna that is wholly flush-mounted in the metallic carrier with enhanced gain in the horizontal direction by using distributed dielectric loading. The wideband and low-profile properties of the monocone antenna are achieved through top hat and shorting pins loading. The affection mechanism of the dielectric loading is studied to mitigate the performance degradation of the flush-mounted antenna. Through optimizing the shape and position of the dielectrics, the propagation direction of the radiated electromagnetic (EM) wave is altered, which effectively regulates the radiation pattern of the antenna. Thus, the horizontal gain is improved remarkably and this feature is very important for omnidirectional communication systems. The proposed antenna is fabricated and measured to verify the design concept. The measured results show that the antenna obtains a frequency band from 0.7 to 1.4 GHz, exhibits a relatively high horizontal gain exceeding −2 dBi in the entire band, and possesses excellent omnidirectional radiation characteristics.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858618","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":"Miniaturized Super Wideband VHF/UHF Monopole Antenna With Integrated Matching Network for Spectrum Monitoring Applications","authors":"Asaf Khan,&nbsp;Qunsheng Cao,&nbsp;Hasan Raza,&nbsp;Gulab Shah,&nbsp;Afzal Ahmed,&nbsp;Hang Yuuan","doi":"10.1002/mop.70355","DOIUrl":"https://doi.org/10.1002/mop.70355","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper presents a novel, extremely low-profile, miniaturized monopole antenna for spectrum monitoring applications. The antenna achieves an unprecedented 100:1 impedance bandwidth (30–3000 MHz), corresponding to a fractional bandwidth of 196%, with a compact size of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>0.03</mn>\u0000 \u0000 <mi>λ</mi>\u0000 \u0000 <mo>×</mo>\u0000 \u0000 <mn>0.03</mn>\u0000 \u0000 <mi>λ</mi>\u0000 \u0000 <mo>×</mo>\u0000 \u0000 <mn>0.00015</mn>\u0000 \u0000 <mi>λ</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $0.03lambda times 0.03lambda times 0.00015lambda $</annotation>\u0000 </semantics></math>, where <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mi>λ</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $lambda $</annotation>\u0000 </semantics></math> is the wavelength at the lowest operating frequency. To address size, weight, and power (SWaP) constraints while extending operation into the challenging 30–300 MHz band, a multi-stage lumped-element matching network is integrated on the antenna's back side. This dual-path matching network enables Ant. 5 (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>0.03</mn>\u0000 \u0000 <mi>λ</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $0.03lambda $</annotation>\u0000 </semantics></math>) to match the low-frequency performance of a much larger antenna (Ant. 4, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>0.24</mn>\u0000 \u0000 <mi>λ</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $0.24lambda $</annotation>\u0000 </semantics></math>), effectively overcoming the size-bandwidth limitation. The antenna achieves a peak gain of 3.6 dBi at 800 MHz and maintains gain above 0 dBi from 360 to 3000 MHz. Measured VSWR remains below 3 from 30 to 38 MHz and below 2 across the remaining of the operational band. Simulated and measured results show excellent agreement, validating the design's suitability for SWaP-constrained platforms such as mobile, airborne, and densely deployed systems. This study offers a transformative solution for broadband spectrum monitoring and direction-finding arrays.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858625","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 High Power Harmonic Filter Realized via Optimized Waffle-Iron","authors":"Hai-Xu Liu,&nbsp;Yong-Hong Zhang","doi":"10.1002/mop.70341","DOIUrl":"https://doi.org/10.1002/mop.70341","url":null,"abstract":"<div>\u0000 \u0000 <p>This letter proposes a beneficial design approach for a high-power reflective harmonic filter based on an optimized waffle-iron. With a non-equidistant periodic array cylindrical architecture, the optimized waffle-iron can reduce the passband transmission loss and suppress second, third, and so forth harmonic reflection. To match the WR137 standard waveguide port, a quarter-wavelength-loaded cylindrical structure's stepped impedance transformation is adopted. The simulation results are largely in agreement with the test results, which show a maximum insert loss of 0.15 dB in the pass-band of 7.1 GHz–7.25 GHz and a minimum harmonic suppression of 60, 65, and 50 dB for the second, third, and fourth, respectively. Heat dissipation analysis and power handling capabilities tests were also performed. With nitrogen filled at 0.12 MPa atmospheric pressure, the continuous wave(CW) power without breakdown is measured over 30 kW. To our knowledge, this is the highest power reflecting harmonic filter in the X-band.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833170","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":"SLM Manufacturing of a Novel Highly Compact Quarter-Sphere Resonator Based Filter","authors":"Xiue Bao,&nbsp;Jinkai Li,&nbsp;Li Wang,&nbsp;Liming Si,&nbsp;Giovanni Crupi,&nbsp;Dominique Schreurs,&nbsp;Haoyun Yuan,&nbsp;Houjun Sun,&nbsp;Zhuangzhuang Liu","doi":"10.1002/mop.70337","DOIUrl":"https://doi.org/10.1002/mop.70337","url":null,"abstract":"<div>\u0000 \u0000 <p>This letter presents a highly compact waveguide-based bandpass filter, which can be used for high-power transmission for satellite communications. The filter consists of a quarter spherical resonator, whose higher-order modes are restricted by introducing four tool cavities. By integrating four spherical resonators into a sphere, a highly compact fourth-order filter with wideband and good out-of-the-band rejection is obtained, whose geometric size is <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>1.24</mn>\u0000 <mspace></mspace>\u0000 \u0000 <mi>λ</mi>\u0000 \u0000 <mo>×</mo>\u0000 \u0000 <mn>1.24</mn>\u0000 <mspace></mspace>\u0000 \u0000 <mi>λ</mi>\u0000 \u0000 <mo>×</mo>\u0000 \u0000 <mn>1.24</mn>\u0000 <mspace></mspace>\u0000 \u0000 <mi>λ</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $1.24,lambda times 1.24,lambda times 1.24,lambda $</annotation>\u0000 </semantics></math>. The spherical filter with complex internal structure is manufactured by using the selective laser melting (SLM) technology, which is a 3D printing technique with a low cost-to-complexity ratio. Finally, measurement results validate the good performance and obvious miniaturization of the developed filter.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833169","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}