Estimation of inner scattering parameters from coupled systems

Accurate and reliable radio frequency scattering matrix measurements require careful considerations about the measurement setup. The network analyzer (NA) is calibrated for its connection points. Any component between the connection point affects the measurement result, e.g. additional lines to the actual device under test (DUT) lead to falsified measurements. De-embedding is used to correct the raw measurement from known influences to the left and to the right side of the DUT. Hence de-embedding provides information about the inner state. In this paper we discuss the reversed scenario. We consider two DUTs, which are connected by means of a transmission line in between. Can we we provide information about the two DUTs from outer scattering matrix measurements?