Radiated susceptibility analysis of RF active circuits enclosed in a slotted cavity

A decoupling analysis technique based on the combination of electromagnetic solvers and circuit tools is presented to evaluate the radiated susceptibility of a radio frequency (RF) active circuit enclosed in a slotted cavity. The adopted decoupling concept separates the analysis of the passive printed circuits and slotted cavity from the nonlinear components. The full-wave electromagnetic field solver is employed for the passive components and printed circuit board. For the analysis of the nonlinear active devices, ADS is adopted. Using this approach, the radiated susceptibility of a typical power amplifier is investigated. Simulated results demonstrate that external electromagnetic field can cause the gain degradation of power amplifier. Furthermore, several measures for improving the electromagnetic interference (EMI) effects on enclosed RF active circuit are proposed. Corresponding simulated examples for those measures show their effectiveness.