Detection of spread spectrum signals using a power-law based intercept receiver

In this paper, we study the performance of the power-law based intercept receiver in detection of spread spectrum signals. The threshold of the intercept receiver is calculated with the Cornish-Fisher algorithm. Numerical results show that the performance of the power-law based receiver can be as good as the performance of the conventional total-power radiometer when a direct sequence code-division multiple-access signal is present, assuming that an optimal fast Fourier transform (FFT) size is used. If suboptimal FFT sizes are used, the performance advantage of the total power radiometer is less than 1 dB. When the signal to be detected is a frequency hopping multiple frequency-shift keying signal, the power-law receivers have better performance than the total-power radiometer, unless the hop rate is very high. The effects of uncertain noise level are studied. The results show that, in this case, the power-law based receivers gain compared to the total power radiometer.