High accuracy range estimation of FMCW level radar based on the phase of the zero-padded FFT

A range estimation technique for FMCW level radar based on the phase of the FFT of the beat-note signal is presented. The ambiguity in phase measurement is eliminated by employing the zero-padded FFT technology. Formula for evaluating the rms (root-mean-square) error of range estimation is derived. Computer Monte Carlo simulation results are also given.