Detection of Frequency-Hopped Waveforms Embedded in Interference Waveforms with Noise

Bandwidth usage has become more complex such that it is not uncommon that multiple signals of appreciable power may be present within the same bandwidth. The presence of multiple signals in addition to additive white Gaussian (AWGN) increases the difficulty of detecting frequency-hopped (FH) waveforms. This paper investigates the performance of an exponential-averaging based FH detection method in the presence of interfering signals and AWGN. The detection method provides an estimate of the noise plus inference spectrum using exponential averaging and then generates an estimate of the desired signal spectrum by combining the estimated noise plus interference spectrum with the composite (desired signal plus interference plus noise) spectrum. Finally, this paper evaluates the detector´s performance as a function of the exponential coefficient, the combining method (division or subtraction), signal-to-AWGN ratio (SNR), and signal-to- interference ratio (SIR).