MODEL OF INSTANTANEOUS FREQUENCY MEASUREMENT RECEIVER WITH PRELIMINARY FREQUENCY MULTIPLICATION AND AUXILIARY CHANNEL BASED ON NONLINEAR SCATTERING PARAMETERS

The article deals with instantaneous frequency measurement (IFM) receiver model. Proposed receiver exploits preliminary frequency multiplication of input signal and auxiliary microwave detector channel. Article goal is investigation of microwave transfer coefficient irregularity compensation method. Another goal is investigation and reduction of measurement error sources. Research goals are reached by mathematical model construction and it further investigation. Mathematical model is based on the nonlinear large signal scattering parameters. Model demonstrates that preliminary frequency multiplication allows reduction of required group delay time of delay line. It is showed that measurement result affected by transfer coefficient irregularity, transfer coefficient instability of receiver chain elements and multiply reflected from irregularities waves. Auxiliary measurement channel and measurement function in the form of voltage ratio at basic channel detector and auxiliary channel detector provide a way to reduce influence of input signal amplitude, instabilities and irregularities of transfer coefficient on the frequency measurement result. It is showed that full reduction of aforementioned factors prevented by parasitic harmonics and multiply reflected waves. Required suppression level of parasitic harmonic are presented. Obtained results can find applications in sphere of electronic warfare and measurement theory and techniques.