Spectrum analyzers are widely used in wireless communications, broadcasting, EMC (electromagnetic compatibility) testing, and more. Unlike VNAs, spectrum analyzers do not measure phase. Instead, they show a graph of power versus frequency, known as a spectrum. Network analyzers mostly measure S-parameters, which are a type of parameter that characterizes the electrical behavior of linear circuits, or more specifically, the input/output relationships of. A network analyzer is a device used to measure the network parameters of electrical circuits.