摘要：The 60-GHz traveling-wave tube （twt） prevails nowadays as the amplifier for the satellite communication and electronic countermeasures. The folded waveguide （FW） is a promising all-metal slow-wave structure （SWS） for the 60-GHz twt with advantages of robust performance, fine heat dissipation, considerable power and bandwidth. A novel FW periodically loaded with rectangular grooves is analyzed for the purpose of gaining higher power and gain. The rf characteristics are investigated by numerical simulation, and the nonlinear large- signal performance of such a twt is analyzed by a 3I） particle-in-cell code MAGIC. Compared with normal circuits, relatively higher continuous-wave power （40-56 W） and similar bandwidth （5 GHz） are predicted by simulation. Meanwhile, the designed operation voltage is 10.5 kV, which keeps the low-voltage advantage of the popular helix twt competitor. The novel FW will favor the design of a broadband and high-power 60-GHz twt

摘要：A new class of compact and lightweight S-band 1 kW traveling-wave tube (twt) is being developed for a microwave power module (MPM) that will be used for phased antenna array radar applications. The proposed S-band MPM provides a tenfold peak power increase compared to state-of-the-art S-band MPMs. In this paper, the design of the vacuum power booster twt part of the MPM is presented. The compact and lightweight S-band twt is driven by a 6 kV, 0.9 A electron beam. The amplifier is predicted by large-signal simulations to generate over 1 kW at S-band with 25 dB saturated gain and over 40% efficiency. The stability from unwanted oscillations has been investigated. To suppress the oscillations, the helix circuit has been coated with carbon composite material. The coaxial input and output antennas have been fabricated. For efficiency enhancement, a multi-stage depressed collector (MDC) has been designed using a 3D particle-in-cell (PIC) simulator, VORPAL. The collector design makes use of a current loop based on a feedback mechanism for effective design process. The integrated designs of a helix circuit, an electron gun, a periodic permanent magnet (PPM), antennas, and a collector are presented.

摘要：根据周期场聚焦电子注的基本理论,利用行波管仿真软件twt设计了某行波管的周期永磁聚焦系统,模拟计算了电子注在周期永磁聚焦系统中的运动状态,分别考虑了峰值磁感应强度对静态理想电子注和电子枪发射的电子注的聚焦,过渡区对电子枪发射的电子注聚焦的影响,分析了电子注在周期永磁聚焦系统中的传输特性,确定了聚焦系统的周期磁场与过渡区磁场分布规律,为实现周期永磁聚焦系统的一次装管成功提供了有价值的参考。

摘要：针对高压输出、宽负载变化的行波管(twt)电源,提出一种基于定频控制的Buck+半桥LLC倍压谐振两级式DC/DC变换器。该变换器通过定频控制解决了变频控制时磁性元件的优化设计问题,并通过合理地选择LLC的工作频率,使LLC的开关管和整流二极管在全负载范围内分别实现了ZVS和ZCS。通过对传统的Cockcroft-Walton倍压整流电路进行改进,得到对称式倍压整流电路,有效地降低了输出电压纹波和电压跌落,却不用增加器件的数量,更适用于高压、小电流输出场合。首先利用电容充放电原理对任意方波输入的倍压整流电路进行定量分析,得到输出电压纹波和电压跌落的公式。其次,从时域对LLC进行详细的稳态分析。然后,对两级式变换器进行优化设计,并给出定频LLC的优化设计方法。最后,通过实验验证了以上分析的正确性。

摘要：Imagination Technologies宣布推出基于其Ensigma Wi Fi技术的最新硅知识产权(IP)产品IMG iEW400。iEW400集成了射频(RF)和基带,专为物联网(IoT)、可穿戴设备和可听戴设备等低功耗和电池供电型应用而设计。iEW400基于最新的IEEE 802.11ax Wi Fi 6标准,可通过如下一系列新功能提供更强大的性能、吞吐量和节能性:以20/40 MHz频宽运行,支持低数据速率应用,以节省电池电量;目标唤醒时间(twt)技术,延长深度休眠时间,显著改善电流消耗并延长电池续航时间;正交频分复用多址(OFDMA)技术.