On the performance of a random reference correlator (Corresp.)

The performance of a random reference correlator (RRC) in terms of its precision is studied. It is shown that the precision depends almost entirely on a certain "peak factor". Processes with high peak factors must be clipped, which creates a compromise between the resulting bias and the optimization of precision. In this case a clipping factor has been defined. It is shown that, for clipping level values between 1 and 1.5 times the rms value, the distortion is reasonably acceptable and the variance of the estimate is of the same order of magnitude as that of direct estimators. A prototype, built with high-speed TTL logic circuits, allows incremental delays of 20 ns to be obtained.