On the Cyclostationary Noise Analysis in Large RF Integrated Circuits

This paper examines the issue of noise analysis in RF integrated circuits (RFICs). The complexity of the RFIC grows constantly, with transistor counts now into the thousands or tens of thousands. Since RFICs are driven by large-signal multitone excitations, the stochastic noise process in these circuits is cyclostationary. This combination of large device count and noise cyclostationarity makes noise analysis in RFICs a time-consuming task. Simulation algorithms that minimize computer memory consumption and computation cost are thus necessary. There is a consensus now that harmonic balance is the most appropriate circuit equation solution method for multitone analysis of RF circuits. The paper thus gives a comprehensive description of a harmonic balance-based algorithm for computing the circuit noise response, showing how it effectively accounts for all types of cyclostationary noise sources supported by modern compact device models. The algorithm has been implemented in a commercial simulator and shows good capabilities for the analysis of full transceiver circuits within reasonable computer memory occupancy and simulation times.