Microwave Deviation Linearity Test Method

Microwave voltage controled oscillators are prominent components in state of the art communications systems. They feature among other things increased bandwidth and frequency responce. It is the intent of this paper to present a quick and reliable method to test device deviation linearity. This method uses the Bessel function measurement technique. The Bessel functions are computer generated graphs normalized to a reference unmodulated carrier vs modulation index. The presentation of this graph is the key factor in reducing the amount of data reduction necessary to present the test results in usable form. This paper also discusses the singularity problem in determining modulation index from multivariate sideband levels.