Modeling RF Systems

Version 1, 6 March 2005 This paper discusses behavioral models of RF blocks. The RF blocks amplify, filter, modulate, and demodulate RF carriers. The paper classifies behavioral RF models as either passband or baseband. Like device-level models, passband models explicitly simulate every cycle of the carrier. However, baseband models suppress the carrier to trade some accuracy for a dramatic increase in execution speed. The first part of this paper explains one way in which behavioral models of RF blocks fit into the design flow. The next two sections describe passband and baseband models. The paper concludes with an example of how behavioral models can help diagnose anomalous lab observations of an OFDM (orthogonal frequency division multiplexing) system.