Coupled circuit/EM simulation for radio frequency circuits

In radio frequency (RF) circuits the lumped model assumptions are often not valid anymore. To circumvent this problem, mixed-level circuit/electro-magnetic/device simulation allows the use of Maxwell's and semiconductor equations for the critical devices and lumped models for the ambient circuitry. Besides AC, DC, periodic steady state and transient analysis, the multirate partial differential equation technique is employed for RF circuitry, based on a spline/wavelet expansion of the waveforms. The novel technique is demonstrated for RF circuits with on-chip inductors, transmission lines and baluns, modeled as 3D devices.