Microwave and Optical Technology Letters最新文献

{"title":"Transient Multi-Physical Field-Circuit and Electro-Thermal Coupling of Dual PIN Diode Limiter","authors":"Zichu Zhang,&nbsp;Shitao Chen,&nbsp;li liang,&nbsp;Ziqing Liu","doi":"10.1002/mop.70378","DOIUrl":"https://doi.org/10.1002/mop.70378","url":null,"abstract":"<div>\u0000 \u0000 <p>In this paper, a method combining the Finite-Difference Time-Domain (FDTD) method and the semiconductor drift-diffusion model (DDM) is presented for analyzing transient electro-thermal characteristics of dual PIN diode microwave limiters. the time domain impulse response signals corresponding to the ports of linear electromagnetic field structures are calculated using the FDTD algorithm. These signals are then coupled with the volt-ampere characteristics as defined by the DDM-based dual-PIN diode model. The transient electro-thermal properties of the dual-PIN diode within the actual microwave limiter circuit are analyzed, with the method's accuracy and efficiency validated through comparison with COMSOL simulation results.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144915215","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 of a Circularly Polarized Wearable SIW Antenna Applied to Off-Body Communication Mode","authors":"Guo-Ping Gao,&nbsp;Wen-Di Guo,&nbsp;Jun-Jie Xia,&nbsp;Xuan Wang,&nbsp;Jing-Hang Dong,&nbsp;Bin Hu","doi":"10.1002/mop.70371","DOIUrl":"https://doi.org/10.1002/mop.70371","url":null,"abstract":"<div>\u0000 \u0000 <p>A circularly polarized wearable substrate integrated waveguide (SIW) antenna working in the WLAN frequency band (5.15–5.825 GHz) is designed with a size of 40 mm × 40 mm × 1.5 mm (0.733 λ₀ × 0.733 λ₀ × 0.0275 λ₀). The proposed antenna is applied to off-body communication and radiates unidirectional patterns. The antenna uses four symmetrical shorting pins to excite the TE₁₂₀ mode and TE₂₁₀ mode of rectangular SIW resonator, which are a pair of degenerate modes, to realize circular polarization. Two pairs of rectangular slots with different sizes are etched on the antenna to cut the current of the SIW resonant cavity, and the resonant frequency points of TE₁₂₀ mode and TE₂₁₀ mode are adjusted together. In addition, a circular ring slot is etched in the center of the antenna to improve the axial ratio and adjust the impedance matching of the antenna. The measured results show that the antenna works at 5.41–5.56 GHz with a relative bandwidth of 2.73%. The proposed antenna is harmless to human body, which can be evidenced by the simulated 1 and 10 g averaged specific absorption rate values.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144910269","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 High-Gain Low-Profile Millimeter-Wave Circularly Polarized End-Fire Antenna Based on Magnetic Dipole Directors","authors":"Sha Xu,&nbsp;Ju Yang,&nbsp;Shaowei Liao,&nbsp;Guiping Jin","doi":"10.1002/mop.70330","DOIUrl":"https://doi.org/10.1002/mop.70330","url":null,"abstract":"<div>\u0000 \u0000 <p>This letter proposes a wideband, high-gain, low-profile circularly polarized end-fire antenna for 5G millimeter-wave applications. The antenna consists of a substrate integrated waveguide (SIW) circularly polarized feeder, dual-polarized directors, and coplanar waveguide (CPW)-SIW transitions, with a low-profile height of 0.14 <i>λ</i>₀. The circularly polarized feeder exhibits wide bandwidth and reliable end-fire radiation, while the dual-polarized magnetic dipole directors enhance the end-fire gain. Based on the feeder and magnetic dipole directors, a circularly polarized antenna is designed and fabricated. The −10 dB impedance bandwidth reaches 29.48%, with a peak gain of 11.14 dBic, demonstrating good impedance matching and high gain within the 5G millimeter-wave band. Furthermore, the entire structure of the proposed antenna can be conveniently implemented using a single-layer PCB substrate, achieving the desired low-profile height.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144910271","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 Low-Profile Circularly Polarized Antenna Array With Considerable Overlapped Impedance and Axial-Ratio Bandwidths for 5G N78 Band","authors":"Tian Liu,&nbsp;Zhicong Chen,&nbsp;Zepeng Cao,&nbsp;Longxiang Jiang,&nbsp;Gaosheng Li,&nbsp;Hao Li","doi":"10.1002/mop.70377","DOIUrl":"https://doi.org/10.1002/mop.70377","url":null,"abstract":"<div>\u0000 \u0000 <p>A compact, low-profile circularly polarized (CP) antenna element is proposed using a two-layer printed circuit board (PCB) configuration. The radiator on the top of the first PCB is a rectangular loop inside with four sector-shaped patches, excited by a cross-slot of the ground on the top of the second PCB. The cross-slot is fed with a Γ-shaped microstrip line on the bottom of the second PCB. Based on this designed method, two CP modes are formed. The measured results show that it has a −10 dB impedance bandwidth (IBW) of 3.23–3.84 GHz (17.26%) and a 3 dB axial-ratio bandwidth (ARBW) of 3.33–3.71 GHz (10.80%), a realized gain of 7.70 ± 0.10 dBi and an average radiation efficiency of 72.56% over ARBW. Furthermore, a 2 × 2 antenna array is constructed using the proposed element and a four-way toroidal power divider network. The array is fabricated and measured with a −15 dB IBW of 3.20–3.94 GHz (20.73%), an ARBW of 3.16–3.96 GHz (22.47%), and a realized gain of 12.05 ± 0.19 dBi over 3.3–3.8 GHz band. Therefore, the left-handed CP array demonstrates that it can be a promising candidate for the 5G n78 systems.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144897667","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 Novel Millimeter Wave Magnetic Probe Based on SIW Transmission Structure","authors":"Rui Chu,&nbsp;Wenquan Che","doi":"10.1002/mop.70363","DOIUrl":"https://doi.org/10.1002/mop.70363","url":null,"abstract":"<div>\u0000 \u0000 <p>A millimeter wave magnetic field probe based on substrate integrated waveguide (SIW) is proposed. The probe comprises a metal via and stripline for detection and a SIW transmission. A taper microstrip line is used between stripline and SIW for field mode transmission and impedance matching. The SIW has low transmission loss at millimeter wave frequency band, which can sustain the flatness and electric field suppression of the magnetic probe. The frequency band of the proposed probe is from 25 to 31 GHz. The electric field suppression ratio in the working band is over 20 dB, and can reach 35 dB at 29 GHz.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144897508","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 Profile-Reduced Transmitarray Antenna Based on Phase-Shifting Elements","authors":"Wei Luo,&nbsp;Xiaoxue Wang,&nbsp;Liu Luo,&nbsp;Yuqi Yang,&nbsp;Min Wang","doi":"10.1002/mop.70379","DOIUrl":"https://doi.org/10.1002/mop.70379","url":null,"abstract":"<div>\u0000 \u0000 <p>A wideband with profile-reduced transmitarray antenna based on phase-shifting elements is proposed in this letter. The element of transmitarray comprises three metal layers with a double-slotted metal ring aperture and two dielectric layers. The stable transmission coefficient is achieved with compact coupled structures. The simulated electric field on the reference plane is analyzed to optimize the focal-to-diameter (<i>F/D</i>) ratio. Furthermore, a precise optimization method by reducing the phase error in the phase compensation scheme is designed to improve the gain bandwidth of antenna. The optimized transmitarray is fabricated and measured, which consists of 20 × 20 elements. The <i>F/D</i> ratio is reduced by 27%, and the 1-dB and 3-dB gain bandwidths are 22.90% and 28.75%. The peak aperture efficiency reaches 43.06%. The optimization scheme can be applied for broadbanding design of transmitarray with a limited profile height.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 9","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144897669","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 of a Wideband Frequency Selective Surface With Low Insertion Loss for a Triple-Band Cryogenic Receiver","authors":"Rongyu Wang,&nbsp;Weiye Zhong,&nbsp;Miao Zhang,&nbsp;Chao Zhang,&nbsp;Jia Ma,&nbsp;Hui Zhang,&nbsp;Yuanyuan Cui","doi":"10.1002/mop.70369","DOIUrl":"https://doi.org/10.1002/mop.70369","url":null,"abstract":"<div>\u0000 \u0000 <p>A wideband and low-insertion-loss frequency selective surface (FSS) is proposed for the K/Q/W-band cryogenic receiver of the Tianma Radio Telescope (TMRT). The FSS is designed to transmit W-band electromagnetic waves (80–110 GHz) while reflecting K-band (18–26 GHz) and Q-band (35–50 GHz) signals. To reduce insertion loss caused by conventional prepreg bonding, a triple-layer air-gap-supported metal-dielectric structure is introduced. Each layer consists of hexagonal copper rings and patches patterned on Rogers 5880 substrates. The FSS achieves a measured insertion loss of 0.21 dB under <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>3</mn>\u0000 \u0000 <msup>\u0000 <mn>0</mn>\u0000 \u0000 <mo>∘</mo>\u0000 </msup>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $3{0}^{circ }$</annotation>\u0000 </semantics></math> oblique incidence, with stable performance under both Transverse Electric (TE) polarization and Transverse Magnetic (TM) polarization. Compared to recent designs, this study achieves a superior trade-off between bandwidth and insertion loss at <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>3</mn>\u0000 \u0000 <msup>\u0000 <mn>0</mn>\u0000 \u0000 <mo>∘</mo>\u0000 </msup>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $3{0}^{circ }$</annotation>\u0000 </semantics></math> incidence, which is critical for quasi-optical systems in millimeter-wave astronomy.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144891781","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":"Mechanical Tuning of Air-Filled Substrate Integrated Waveguide Cavities by Employing Dielectric Rods","authors":"Nicolò Delmonte,&nbsp;Riccardo E. Saino,&nbsp;Cristiano Tomassoni,&nbsp;Maurizio Bozzi","doi":"10.1002/mop.70376","DOIUrl":"https://doi.org/10.1002/mop.70376","url":null,"abstract":"<p>This study presents a simple method to obtain tunable cavity resonators in air-filled substrate integrated waveguide (AFSIW) technology. It is based on the insertion of a dielectric rod from an opening placed on a side of the SIW cavity, whose resonance frequency is varied by changing the penetration depth of the rod. To avoid power leakage, a short SIW section below cutoff is connected to the opening. The applications of this method include postproduction compensation for manufacturing inaccuracies and possibly the tuning of cavity filters. The proposed method is numerically and experimentally demonstrated through a frequency reconfigurable filter, operating at 5 GHz with a tuning range of ±200 MHz (8%).</p>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mop.70376","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144891782","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":"Design of a Compact Microstrip Box-Like Bandpass Filter With High-Frequency Selectivity and Excellent Stop-Band Performance","authors":"Jun-Mei Yan,&nbsp;An-Qi Tong,&nbsp;Liang-Zu Cao","doi":"10.1002/mop.70340","DOIUrl":"https://doi.org/10.1002/mop.70340","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper presents a compact box-like microstrip bandpass filter. It features high-frequency selectivity and excellent stopband performance. It comprises a half-wavelength stepped-impedance resonator (SIR) and three quarter-wavelength SIRs. The half-wavelength and quarter-wavelength SIRs are hybrid adopted. Therefore, the second-order parasitic passband is suppressed effectively. Simultaneously, through controlling the ratio of the stepped impedance, the third-order resonant frequencies are separated properly, which effectively suppresses the third-order parasitic passband. The filter has a box-like coupling topology, which can introduce one transmission zero, and its position can be located at arbitrary side of the passband. Furthermore, tapped-line is used to accomplish the external coupling, which can introduce two transmission zeros for the so-called zero-feeding structure. The three transmission zeros give the filter a high-frequency selectivity. Additionally, the carefully arranged geometrical layout with box-like coupling topology provides the filter with a miniaturized size. A prototype filter centered at 1.8 GHz, with FBW of 4.0%, is designed, fabricated, and measured. Its structure, operational mechanism, and design steps are discussed in detail. The simulated and measured results are given, and a good agreement between them verifies the effectiveness of the proposed filter and design method.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144891780","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":"Compact Dual-Frequency Dual-Circularly Polarized Feed for Ku-Band Satellite Communication Applications","authors":"Qia Wang,&nbsp;Jixiang Wan,&nbsp;Hao Wang,&nbsp;Xiao Tao,&nbsp;Qingli Lv,&nbsp;Langtao Bai,&nbsp;Li Yu,&nbsp;Naixin He","doi":"10.1002/mop.70368","DOIUrl":"https://doi.org/10.1002/mop.70368","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper presents a compact dual-circularly polarized (dual-CP) feed operating in Ku transmitting (Tx) and receiving (Rx) bands for spaceborne flexible multi-beam reflector antennas. A novel approach based on a broadband septum circular polarizer (30.16% fractional bandwidth) is adopted in the dual-band dual-CP network, integrated with two compact corrugated diplexers and two 90° polarization-rotating structures, leading to a significant reduction in transverse size. A wideband profiled smooth-wall horn antenna is integrated with the proposed network, resulting in a feed with a transverse dimension of only <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mn>1.83</mn>\u0000 \u0000 <msub>\u0000 <mi>λ</mi>\u0000 \u0000 <mi>L</mi>\u0000 </msub>\u0000 <mspace></mspace>\u0000 \u0000 <mtext>×</mtext>\u0000 <mspace></mspace>\u0000 \u0000 <mn>1.83</mn>\u0000 \u0000 <msub>\u0000 <mi>λ</mi>\u0000 \u0000 <mi>L</mi>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $1.83{lambda }_{L},text{unicode{x000D7}},1.83{lambda }_{L}$</annotation>\u0000 </semantics></math> @11.7 GHz. The feed offers left- and right-hand circular polarization (CP) separation and sub-band discrimination (Tx: 10.7–12.7 GHz and Rx: 14–14.5 GHz). The fabricated prototype exhibits return loss better than 17.6 dB and polarization ports isolation greater than 20.7 dB for both CPs in the two bands. It also achieves gains over 12.7 dBic and maintains axial ratios below 1.36 dB. This design ensures transverse compactness, bandwidth, and efficiency, facilitating the dense arrangement of elements within the feed array.</p>\u0000 </div>","PeriodicalId":18562,"journal":{"name":"Microwave and Optical Technology Letters","volume":"67 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144891783","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}