Simulation methods for RF integrated circuits
Proceedings of IEEE International Conference on Computer Aided Design (ICCAD) ICCAD-97
The principles employed in the development of modern RF simulators are introduced and the various techniques currently in use, or expected to be in use in the next few years, are surveyed. Frequencyand time-domain techniques are presented and contrasted, as are steady-state and envelope techniques and large-and small-signal techniques. I. RF CIRCUITS The increasing demand for low-cost mobile communication systems has greatly expanded the need for simulation algorithms that are both efficient
... e both efficient and accurate when applied to RF communication circuits. RF circuits have several unique characteristics that are barriers to the application of traditional circuit simulation techniques. Over the last decade, researchers have developed many special purpose algorithms that overcome these barriers to provide practical simulation for RF circuits, often by exploiting the very characteristic that represented the barrier to traditional methods. Despite dramatic progress, the average design cycle of an RFIC is still twice the length of that for other ICs found in a communication system, such as a cellular phone. This represents a significant practical barrier to integration of the RF and baseband sections of a transceiver onto a single chip. Clearly, more progress is necessary. This paper is a overview of RF simulation methods that seeks to provide an understanding of how the various methods address the RF simulation problem, and how they relate to each other. It begins by describing the unique characteristics of RF circuits. The basic solution methods of transient analysis, harmonic balance, and shooting methods are presented and contrasted. Small-signal analysis versions of both harmonic balance and shooting methods are covered. Composite methods are next. These methods apply the base methods in layers to provide dramatic new capabilities.