Towards a denser frequency grid in phase measurements using mixer-based receivers

Abstract

In this paper a new method to achieve a dense frequency grid in synchronous phase measurements is presented. This technique is suitable to use with instruments that employ a mixer-based internal architecture. Contrary to other works, the grid density is not being enhanced through the increase of the comb-generator (CG) output tone density, nor through the use of successive multi-sine waveforms. The technique proposed uses the same reference signals for any band measurable by the instrument. Besides, the power of each CG output tone is also kept at a high level. The tradeoff is the requirement for wide-band receivers, which are already commonly present in modern instrumentation. Multi-sine phase measurements performed with a nonlinear vector network analyzer (NVNA) will be compared with results obtained using the new technique (and performed by commercial mixer-based receivers). The comparisons will be used to validate the suggested method.