Ziang Zhang;Jianing He;Qin Chen;Xuhao Jiang;Xiangning Fan;Lianming Li
{"title":"A DC-51.5 GHz Digital Step Attenuator With Sub-5 dB Insertion Loss and 3.1° RMS Phase Error","authors":"Ziang Zhang;Jianing He;Qin Chen;Xuhao Jiang;Xiangning Fan;Lianming Li","doi":"10.1109/LMWT.2025.3555936","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3555936","url":null,"abstract":"This article presents an ultrawideband and low-loss digital step attenuator (DSA) with a 15.5-/0.5-dB attenuation range/step. To reduce the insertion loss (IL), a merged attenuation cell is proposed to realize 4-/8-/12-dB attenuation. Moreover, a bridge capacitor is adopted in the merged attenuation cell to expand the bandwidth of the proposed DSA while reducing the phase error between different attenuation states. The proposed DSA is fabricated with a 65-nm bulk CMOS process with a compact core area of only 0.026 mm<sup>2</sup>. With measurements, over the entire operating bandwidth from dc to 51.5 GHz, it achieves an IL of less than 5 dB and root-mean-square (rms) attenuation/phase errors of less than 0.25 dB/3.1°, respectively.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"780-783"},"PeriodicalIF":0.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"IEEE Microwave and Wireless Technology Letters Information for Authors","authors":"","doi":"10.1109/LMWT.2025.3547168","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3547168","url":null,"abstract":"","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 4","pages":"C3-C3"},"PeriodicalIF":0.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10967026","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Interleaved 1×8 Dual-Polarized L-Band Phased Array With Digital Transmit/Receive Beamforming Using RFSoC","authors":"Peizhuo Yang;Alessio Tornese;Gong Chen;Koen Mouthaan","doi":"10.1109/LMWT.2025.3554001","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3554001","url":null,"abstract":"A <inline-formula> <tex-math>$1boldsymbol {times }$ </tex-math></inline-formula>8 dual-polarized L-band transmit/receive phased array, comprising four interleaved arrays, combined with an radio frequency system-on-chip (RFSoC) is presented. Full simultaneous digital beamforming (DBF) on transmit and receive in two polarizations is realized. The design of the array and the synchronization and calibration of the RFSoC channels are discussed, as well as the implementation of the beamformer trading memory usage against processing speed. Direct measurement of coupling coefficients between antenna elements using the RFSoC is also investigated and compared with scattering parameter measurements. DBF receive patterns for the two polarizations are measured when steering the main beam between <inline-formula> <tex-math>$boldsymbol {pm 20^{circ }}$ </tex-math></inline-formula>. Finally, DBF transmit patterns are shown for beamsteering and for two dual-beam cases.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"912-915"},"PeriodicalIF":0.0,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"AlN/GaN MIS-HEMT With GeN Gate Dielectric for mm-Wave Applications","authors":"Jianchao Wang;Kaiyu Wang;Ruizhe Zhang;Xiaoqiang He;Sheng Zhang;Jiaqi Guo;Jiebin Niu;Yankui Li;Weichao Wu;Weijun Luo;Xiaojuan Chen;Sen Huang;Xinhua Wang;Ke Wei;Xinyu Liu","doi":"10.1109/LMWT.2025.3553152","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3553152","url":null,"abstract":"In this work, a high-performance AlN/GaN metal–insulator–semiconductor high electron mobility transistor (MIS-HEMT) with germanium nitride (GeN) as a gate dielectric was fabricated. The gate dielectric was deposited using thermal evaporation and nitridation methods to prevent interface damage and fixed charges caused by plasma growth or sputtering. With the developed nitride-GeN dielectric, the MIS devices exhibit excellent electrical characteristics, including a negligible hysteresis of 0.05 V, a four-order reduction in gate leakage current, and an enhanced gate swing voltage. For a 150-nm gate length, the device achieved a maximum drain current density of 2.03A/mm and an effective current-gain cutoff frequency/maximum oscillation frequency (<inline-formula> <tex-math>$f_{mathrm {T}}$ </tex-math></inline-formula>/<inline-formula> <tex-math>$f_{mathrm {MAX}}$ </tex-math></inline-formula>) of 81/131 GHz. At 30 GHz, it delivered a remarkable power density of 3.9 W/mm at <inline-formula> <tex-math>$V_{mathrm {DS}} =12$ </tex-math></inline-formula> V in the CW mode. These promising results indicate that GeN could be a new and attractive gate dielectric option for AlN/GaN HEMTs functioning in the Ka-band frequency range.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"896-899"},"PeriodicalIF":0.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A 16.6-to-34.1 GHz Dual-Core Quad-Mode Oscillator Achieving 202.3 dBc/Hz FoMT in 65nm CMOS","authors":"Xin Yu;Xiaolong Liu","doi":"10.1109/LMWT.2025.3556280","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3556280","url":null,"abstract":"This work presents a millimeter-wave (mm-wave) dual-core quad-mode oscillator incorporating a switch-less tertiary loop to extend the frequency tuning range (FTR) without introducing additional switch loss or parasitic. The design couples two identical transformer-based dual-band (low- and high-frequency) voltage-controlled oscillators (VCOs), which are configurable in either even or odd modes via mode switches. In the high- and low-frequency band, the switch-less tertiary loop functions as an open circuit in the even mode and a short circuit in the odd mode, enabling four distinct frequency modes. Fabricated in a 65-nm CMOS process, the proposed oscillator achieves an FTR from 16.6 to 34.1 GHz, with phase noise ranging from −122.4 to −130.0 dBc/Hz at a 10-MHz offset, while consuming 9.5–11mW of power. This results in a peak FoM of 185.5 dBc/Hz and FoM<sub>T</sub> of 202.3 dBc/Hz.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"694-697"},"PeriodicalIF":0.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A 66–160 GHz Broadband Frequency Multiplier Chain (×6) With High Harmonic Suppression","authors":"Zi'ang Xu;Zihan Zhang;Junjie Zhang;Xiaoyu Zhang;Guangbo Wang;Jian Guo","doi":"10.1109/LMWT.2025.3556003","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3556003","url":null,"abstract":"This letter presents a 66–160 GHz <inline-formula> <tex-math>$times 6$ </tex-math></inline-formula> frequency multiplier chain (FMC) in 0.1-<inline-formula> <tex-math>$mu $ </tex-math></inline-formula>m pHEMT technology with good harmonic suppression performance. The FMC chip integrates four cascaded stages, including a driver amplifier (DA) with a semi-lumped low-pass filter (SLLPF), a double-balanced tripler with a semi-lumped high-pass filter (SLHPF), a balanced DA, and a double-balanced doubler which are designed rigorously for specific harmonic suppression. Balanced configurations join with semi-lumped filters and wideband passive multipliers to achieve broad bandwidth (BW), power flatness, and excellent harmonic suppression. The measured 3-dB BW of the FMC is 66–160 GHz (relative BW of 83.2%), and the measured peak output power is 7 dBm. The harmonic suppression reaches over 25 dBc within 87–160 GHz (relative BW of 59.1%). To the best of our knowledge, the proposed FMC exhibits the widest relative BW, high harmonic suppression, and comparable output power.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"742-745"},"PeriodicalIF":0.0,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A W-Band Pseudo-Differential CMOS Switching Rectifier for Wireless Power Transfer","authors":"Mengru Yang;Pingyang He;Dixian Zhao","doi":"10.1109/LMWT.2025.3553959","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3553959","url":null,"abstract":"This letter presents a W-band pseudo-differential CMOS switching rectifier for wireless power transfer (WPT). The transistor pair serves as switches to enable full-wave rectification, achieving enhanced power conversion efficiency (PCE) compared to conventional single-ended (SE) designs. To maintain phase-aligned ac waveforms between the gate and drain terminals, effective magnetic coupling is introduced by means of nested inductors while facilitating a compact layout floor-plan. Fabricated in a 40-nm bulk CMOS process, the proposed rectifier demonstrates the measured PCE exceeding 20% for input power between 10–18 dBm. The peak PCE reaches 35% with an optimal load of <inline-formula> <tex-math>$20~{Omega }$ </tex-math></inline-formula> at 94 GHz. At 18-dBm input power, over 24% PCE is realized across 90–99 GHz. The core area is <inline-formula> <tex-math>$180times 140~{mu }$ </tex-math></inline-formula>m.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"698-701"},"PeriodicalIF":0.0,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohamed M. Fahmi;Michael E. MacDonald;Aly E. Fathy;Mohamed D. Abouzahra
{"title":"50-Way W-Band All Waveguide Radial Combiner Design","authors":"Mohamed M. Fahmi;Michael E. MacDonald;Aly E. Fathy;Mohamed D. Abouzahra","doi":"10.1109/LMWT.2025.3554515","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3554515","url":null,"abstract":"This letter presents a novel and challenging design of a 50-way all-waveguide W-band radial combiner, utilizing WR10 ports for all connections. The novelty lies in its pioneering design and implementation of the radial combiner structure, while the challenges stem from the complexities associated with high-frequency design, manufacturing precision, and the integration of multiple waveguide sections. The design begins with a radial combiner featuring rectangular waveguide peripheral ports and a circular waveguide intermediate port operating in the TE<sub>01</sub> mode, which is particularly advantageous due to its low loss, attributed to its field distribution with minimal surface current density. A mode transducer is designed to convert the intermediate circular waveguide TE<sub>01</sub> mode to the dominant TE<sub>10</sub> mode in the WR10 rectangular waveguide. This transducer is integrated with the radial combiner to produce a standard WR10 waveguide output. The design follows a modular approach, dividing the process into separate optimally designed blocks, which are then integrated to form the final structure. Mechanical considerations are crucial at such high frequencies, and all features, such as matching disks and bifurcations, are designed to require only simple mechanical tooling. The design is thoroughly discussed, and an experimental prototype was fabricated and tested, demonstrating good performance without the need for tuning.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"792-795"},"PeriodicalIF":0.0,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pengfei Li;Kaixue Ma;Yudan Zhang;Jiaming Zhao;Hao Shi
{"title":"A 1.53-mm2 Fully Integrated Wi-Fi 7 Front-End Module With 1.65-dB NF and 41.9% FBW in 0.25-μm GaAs p-HEMT Technology","authors":"Pengfei Li;Kaixue Ma;Yudan Zhang;Jiaming Zhao;Hao Shi","doi":"10.1109/LMWT.2025.3553944","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3553944","url":null,"abstract":"This letter presents a highly integrated front-end module (FEM) in 0.25-<inline-formula> <tex-math>$mu $ </tex-math></inline-formula>m gallium arsenide (GaAs) pseudomorphic high-electron-mobility transistor (p-HEMT) process for Wi-Fi 7 applications. The design incorporates a wideband low-noise amplifier (LNA) with a feedforward capacitor structure (FCS) demonstrating 74% fractional bandwidth (FBW) and 1.65–2.3-dB noise figure, a three-stage nonlinear power amplifier (PA) with dynamic bias optimization achieving 16.2–16.5-dBm output power and 8.5% power-added efficiency (PAE) at −43-dB error vector magnitude (EVM) for 320-MHz 4096-QAM signals under digital predistortion (DPD) and a co-designed switch with absorptive electrostatic discharge (ESD) protection supporting human body model (HBM) 2 kV. The measured results show small-signal gains of 11.9–13.9 and 28.5–31.5 dB in receive (RX) and transmit (TX) modes across 4.9–7.5 GHz. Implemented in the smallest reported die area of <inline-formula> <tex-math>$0.9times 1.7$ </tex-math></inline-formula> mm<sup>2</sup>, this work demonstrates superior integration density and performance for next-generation Wi-Fi systems.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"876-879"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chunfeng Fan;Yuexiao Hao;Ke Gong;Yan Liu;Jintu Sun;Qing Liu;Yufang Liu
{"title":"Compact Self-Packaged Hybrid SIW Bandpass Filters With Controllable Finite Transmission Zeros","authors":"Chunfeng Fan;Yuexiao Hao;Ke Gong;Yan Liu;Jintu Sun;Qing Liu;Yufang Liu","doi":"10.1109/LMWT.2025.3552357","DOIUrl":"https://doi.org/10.1109/LMWT.2025.3552357","url":null,"abstract":"This letter proposes two novel compact bandpass filters (BPFs) based on a self-packaged hybrid structure of substrate integrated waveguide (SIW) and stripline. The proposed filters can be equivalent to a box-like coupling scheme with several controlled diagonal cross-coupling paths, thereby providing a flexible response characterized by finite transmission zeros (FTZs). Three to four FTZs can be generated and analyzed, with flexible position adjustments. Finally, two SIW BPFs are fabricated and measured. The test results validate the feasibility of the hybrid SIW filters. Meanwhile, the use of the proposed hybrid technique achieves high selectivity and a 65% reduction in size.","PeriodicalId":73297,"journal":{"name":"IEEE microwave and wireless technology letters","volume":"35 6","pages":"682-685"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144299218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}