Modelling of microwave elements using TLM simulators

Design of nonlinear microwave and millimetre wave circuits is highly demanding. This is attributed, among other factors, to the multimode behaviour of the transmission medium. This makes it difficult to predict the operation of nonlinear circuits with confidence. It is also impossible to arrive at closed-form design formulae which are accurate for all circumstances. Electromagnetic simulations, and in particular the transmission line matrix method, have proven to provide an accurate field insight into the behaviour of high frequency passive circuits. The author introduces a fast three dimensional TLM simulator, together with a new method of extracting the S-parameters of microwave circuits and includes a practical example of a microstrip low pass filter