微波功率模块（MPM）是真空电子器件和固态电子器件组合而成的一种新型微波功率器件，具有频率高、频带宽、功率大、体积重量小等特点，它使常规行波管的应用变得更加便利和广泛。现代战争向雷达、电子战综合一体化方向发展，这就要求功放既能工作在高峰值功率、低占空比的高模工作方式，也能工作在低峰值功率、准连续波的低模工作方式，针对这一需求，结合电子系统收发共孔径的要求，提出了T/R双模MPM技术。T/R双模MPM技术的核心是T/R双模行波管，基于三端口双向T/R行波管，通过在慢波系统的衰减器附近设置一个耦合口，实现行波管的信号反向接收功能；通过T/R双模行波管设计、双模放大均衡组件、双调制栅极电源等技术实现MPM的双模双向功能。T/R双模MPM应用前景广阔，特别是在基于无人机平台的作战应用中的具有明显优势。

This article presents an 8-element dual-polarized phased-array transceiver (TRX) front-end IC for millimeter-wave (mm-Wave) 5G new radio (NR). Power enhancement technologies for power amplifiers (PA) in mm-Wave 5G phased-array TRX are discussed. A four-stage wideband high-power class-AB PA with distributed-active-transformer (DAT) power combining and multi-stage second-harmonic traps is proposed, ensuring the mitigated amplitude-to-phase (AM-PM) distortions across wide carrier frequencies without degrading transmitting (TX) power, gain and efficiency. TX and receiving (RX) switching is achieved by a matching network co-designed on-chip T/R switch. In each TRX element, 6-bit 360° phase shifting and 6-bit 31.5-dB gain tuning are respectively achieved by the digital-controlled vector-modulated phase shifter (VMPS) and differential attenuator (ATT). Fabricated in 65-nm bulk complementary metal oxide semiconductor (CMOS), the proposed TRX demonstrates the measured peak TX/RX gains of 25.5/21.3 dB, covering the 24?29.5 GHz band. The measured peak TX OP1dB and power-added efficiency (PAE) are 20.8 dBm and 21.1%, respectively. The measured minimum RX NF is 4.1 dB. The TRX achieves an output power of 11.0?12.4 dBm and error vector magnitude (EVM) of 5% with 400-MHz 5G NR FR2 OFDM 64-QAM signals across 24?29.5 GHz, covering 3GPP 5G NR FR2 operating bands of n257, n258, and n261.

介绍了大功率高效率功率放大器（功放）在实际设计时面临的晶体管寄生效应问题，并通过引入晶体管封装寄生模型对本征端阻抗进行等效迁移，进而提高了输出匹配网络设计的便捷性。提出一种基于紧凑型微带谐振单元的电路设计方法及其传输线拓扑结构，其中，紧凑型微带谐振单元的作用是提供功放在三次谐波所需的开路点，从而通过调谐传输线满足相应阻抗条件。其优点还包括：基波频率下插入损耗低、效率高；实际物理尺寸小，可满足小型化需求。为了更好地验证上述理论，基于10 W GaN HEMT CGH40010F晶体管和大功率高效率E/F开关类功放在2.2 GHz的工作频率下进行了具体的电路设计。仿真结果表明，该款功放的最大功率附加效率可达78.4%，最大输出功率可达40.1 dBm，功率增益为12.1 dB。

High-power femtosecond mid-infrared (MIR) lasers are of vast importance to both fundamental research and applications. We report a high-power femtosecond master oscillator power amplifier laser system consisting of a single-mode Er:ZBLAN fiber mode-locked oscillator and pre-amplifier followed by a large-mode-area Er:ZBLAN fiber main amplifier. The main amplifier is actively cooled and bidirectionally pumped at 976 nm, generating a slope efficiency of 26.9%. Pulses of 8.12 W, 148 fs at 2.8 μm with a repetition rate of 69.65 MHz are achieved. To the best of our knowledge, this is the highest average power ever achieved from a femtosecond MIR laser source. Such a compact ultrafast laser system is promising for a wide range of applications, such as medical surgery and material processing.

单片集成式主振荡功率放大器（MOPA）具有体积小、功率大、光束质量高等优势，通过集成布拉格光栅，还能够实现窄线宽和动态单模，在倍频、泵浦、光通信和传感等领域具有重要应用价值，是近年来半导体光电子器件的研究热点。本文梳理了单片集成式MOPA的主流结构，包括锥形、脊型、布拉格光栅型和三段式MOPA，以各自的工作原理和性能特征为出发点，介绍其主要的研究方向，并结合它们各自面临的问题介绍最新的发展趋势。针对单片集成式MOPA中普遍存在的高功率下光束质量退化的问题，梳理了近年在外延层结构、腔面光学薄膜和电极设置等方面的优化设计，重点总结了单片集成式MOPA在提高光束质量及高功率、容线宽及高亮度方面的重要进展。围绕不同领域的应用需求，整理了具备高功率、窄线宽、高光束质量和高亮度等性能特征的单片集成式MOPA的研究进展，最后展望了单片集成式MOPA的发展趋势。