Developing a pulsed VNA, observations and experiences

Over the past year a group of us at EIP Microwave have been converting a CW VNA into a system capable of measuring devices while in a pulsed RF mode. As we experimented with the CW VNA it became obvious that the problem was not with measuring a nonlinear device but with removing the nonlinearities form the CW measurement system. In this paper I will be discussing some of the tradeoffs which must be made when measuring pulsed signals and lend some insight into how they can be resolved. Even though the work described was toward the development of a commercial product the observations made will be valuable to anyone who is considering making pulsed vna measurements.