Modeling and Simulation of Nonlinear Faults in Satellite Receivers

Receiver equipment failure and performance degradation caused by nonlinear effects have always been important challenges faced by satellite communication systems. In response to this problem， this paper proposes a nonlinear receiver failure analysis method based on behavioral models. Firstly， this paper derived and analyzed the manifestation of the reflection interference in the filter on the amplitude-frequency response， so as to construct the fault description model of the filter. Secondly， the coefficients of the Saleh model were corrected by the amplitude-phase conversion relationship， and the nonlinear distortion model that characterizes the amplifier in different degrees under the oversaturation point was established. Then， in view of the influence of phase noise correlation on oscillator frequency stability， a first-order autoregressive model was used to characterize the nonlinear faults in the oscillator under different phase noises with different correlations. Finally， the fault models of the filter， power amplifier and oscillator were cascaded to establish the overall nonlinear fault model of the receiver RF front end， and the model was simulated， analyzed and verified through three aspects： constellation diagram， power spectrum and circuit simulation. The experimental results show that the fault behavior model established in this paper can effectively characterize the nonlinear faults in the radio frequency front end of the receiver.