Separation of high and low frequency behavior in non-linear circuit simulation, excited with modulated signals

Exciting nonlinear circuits with modulated signals will generate crossmodul ation frequencies. In ordinary simulation techniques this makes time steppi ng methods a necessity, In the case of EMC-testing where the carrier freque ncy is as high as 2 GHz and the modulating frequency only 1 kHz, the simula tion time will be extremely long. This paper presents Time Domain Frequency Separation (TDFS), a method,where the high and low frequency behavior is c alculated separately to decrease the computation time. In a simulation made with Saber the calculation took approximately fourteen hours, and with TDF S in Matlab two minutes.