Operating Characteristics for Combiner with a Dead Zone in Each Channel.

摘要

Some data processing shortcuts are often required in order to keep the computational burden in today's detection and tracking systems within manageable limits. Here, we investigate a technique, where all levels below a breakpoint or threshold value are rejected, that is, set to zero, while those signal levels above the breakpoint are retained in their full accuracy. The receiver operating characteristics, namely detection probability versus false alarm probability, for a combiner which employs nonlinearities with dead zones in each of its channels, are derived in closed form, as a function of: N, the number of channels; F, the fraction of data passed by the nonlinearity in each channel; R, the signal-to-noise ratio in each channel; and T, the system output threshold. Plots of these results for N = 1, 2, 4, 6, 8, 16, 32, 64 and F = 1, .1, .01, .001 reveal that inclusion of the dead zone does not significantly degrade performance, the typical loss being of the order of 1 dB for small N, and 3 dB for larger N, in the important operating ranges. The only limitation is that certain ranges of false alarm probabilities are achievable; however, since these ranges generally correspond to undesirable operating conditions, the limitation is not too relevant. Keywords: Matched filters, Breakpoint of threshold. (rh)