Design and experimental verification of active RF front-end limiter with high isolation degree and nanoseconds response time

Present RF front-end limiters were widely used to prevent physical damage to low noise amplifier or mixer circuits in the environment of HIRF and EMP radiation. As the limiters were generally designed on the base of passive PIN diode circuits, their output limited power was greater than 10 dBm, which could result in saturation of LNA and degradation of the receiver channel. In this paper, the design methods and experimental verification of a kind of RF front-end active limiter module with ultra-low limited output power were presented. The module consisted of a high power limiting module, an active control module and a low power limiting module, and it featured rather high isolation degree and short response time compared with commonly utilized passive PIN diode limiters.