本文介绍用于S波段雷达收发信道转换的谐振式单刀双掷开关(RSPDT)。该开关具有体积小、重量轻、插损小、成本低和可靠性好等优点,电路调试也比较方便。开关隔离度是微波开关的关键指标,该指标的优劣除受到管子参数限制外,还与电路设计方法有关。本文除根据PIN二极管正、反偏等效电路和一般串联型单刀单掷开关(SPST)的工作原理,分析了管子参数对开关性能的影响,并在选用管子时给予一定考虑(选用末加管壳封装的二极管)外,还比较详细地讨论了用最低成本获取较高开关隔 This article describes a resonant single-pole double-throw switch (RSPDT) for S-band radar transmit and receive channel switching. The switch has the advantages of small size, light weight, small insertion loss, low cost and good reliability, the circuit debugging is also more convenient. Switch isolation is a key indicator of the microwave switch, the merits of the indicator in addition to subject to the parameters of the tube, but also with the circuit design methods. In this paper, based on the PIN diode forward and reverse bias equivalent circuit and the general series SPST (SPST) working principle, the analysis of the pipe parameters on the switching performance, and in the selection of the pipe to give some consideration (optional end pipe Shell diode), but also discussed in more detail with the lowest cost access to the higher switch compartment