南京固体器件研究所研制的供卫星通信地面站用的W205型4GHz非冷参放系统(如图所示),已于1979年底通过定型考核。该系统采用了截止频率f_c≥600GHz的变容二极管、5mm的耿氏泵源和高性能的四端环行器。在设计腔体时已照顾到防止空闲和频泄露问题。小心地把信号频率和这两个频率分隔开是获得低噪声的关键之一。整机采用热电致冷恒温,所有部件工作在20℃。 Developed by the Nanjing Institute of solid-state equipment for satellite communications ground station W205-type 4GHz non-cold gating system (shown), has passed the final assessment by the end of 1979. The system uses a cut-off frequency f_c ≥ 600GHz varactor diodes, 5mm Gunn pump source and high-performance four-terminal circulator. Care has been taken in the design of the cavity to prevent the issue of free and frequency leakage. Careful separation of the signal frequency from these two frequencies is one of the keys to achieving low noise. Machine thermoelectric cooling constant temperature, all parts work at 20 ℃.