LABORATORY PERFORMANCE OF SPREAD-SPECTRUM DETECTORS

The laboratory performance of four spread-spectrum (SS) detectors (ful l-band and partial-band radiometers, chip-rate detector (CRD) and squa ring carrier detector) was measured for direct sequence (DS) and frequ ency hop (FH) SS signals, FH/DS hybrids, and time hop (TH) DS signals. Probability of detection as a function of input SNR for a constant fa lse-alarm rate was measured for numerous combinations of SS waveform a nd detector. Theories were compiled from the literature and extended a s necessary to provide a unified theoretical description. The results usually agreed with theory to within 1 dB. A constant-false-alarm-rate method was used to reduce the drift problem of radiometers. The fact that chip-rate and squaring-carrier detectors have a much reduced drif t problem was confirmed. It is concluded that the four SS detectors us ed are relatively simple and inexpensive devices with laboratory detec tion performance close to theoretical.