Modeling and analysis of nonlinearities and mismatches in AC-coupled direct-conversion receiver

This paper analyzes the effects of circuit nonlinearities and mismatches on the performance of an ac-coupled direct-conversion receiver (DCR). An analytical solution is necessary, since quantifying the DCR performance by simulation can be prohibitively slow. Our analysis approach first transforms the receiver front end to an equivalent baseband continuous-time receiver model with all of the noise sources referred to just before the sampler. Accurate approximations were made throughout this process to make the analysis tractable. The baseband continuous-time model can be further simplified and combined with the baseband equivalent propagation channel model. The resulting model allows the end-to-end performance of an ac-coupled DCR to be quickly and accurately quantified.