Quantization noise spectrum and radar MTI processing

The power density spectrum of analog-to-digital (A/D) converter quantization noise is obtained for pulsed and sampled CW radars. While this type of noise is often assumed to be uncorrelated or `white´, it may not be when a small number of quantization levels are occupied by the input signal or the sampling rate (pulse repetition rate) is large compared with the input clutter spectrum bandwidth. The shape of the quantization error spectrum will determine how much of the error noise passes through the low-pass moving target indication (MTI) filter. This shaping of the quantization error spectrum could possible enhance the performance of the MTI processor. Equations describing the quantization noise power density spectrum at the output of an A/D converter are presented, and curves indicating degrees of spectrum whiteness are given. Specific application to MTI radars is addressed