Noise analysis of digitised FMCW radar waveforms

A staircase phase approximation for generating a linear frequency-modulated continuous wave radar signal is considered and the use of filtering on the samples of the signal has been assumed in both transmission and reception. It is shown that an excellent spectrum of the radar signal can be obtained, provided that the appropriate value of the sample duration is used. The effect of noise due to the discrete representation of the signal is analysed for both transmitted and received signal. It is shown that the level of the noise may be kept below the noise level of a high-quality oscillator even in the absence of any filter smoothing.