Electromagnetic Sensitivity Analysis of RF Front End of Software Defined Radio

In view of the functional failure or safety of the key components of the Software defined radio (SDR) communication link caused by electromagnetic pulse, the electromagnetic sensitivity of the lower noise amplifier (LNA) in radio frequency front end is discussed in this manuscript. By analyzing the electromagnetic topology and coupling mechanism of interference to typical SDR communication links, the equivalent circuit of LNA is designed. ADS is used to simulate and analyze the electromagnetic sensitivity of LNA in radio frequency front end to extract the sensitivity threshold to electromagnetic pulse. The behavior characteristics of the pole current signal of the Pseudomorphic High Electron Mobility Transistor (PHEMT), key part of the LNA, is studied, and the damage model of different stages of PHEMT is established. The equivalent electromagnetic sensitivity model of LNA is finally obtained and analyzed by simulation. The results show that the PHEMT characteristic model can well reflect the damage characteristics of LNA at all levels.