The effect of Ricean fading and partial-band interference on linear and noise-normalized fast frequency-hopped MFSK constant energy/hop receivers

An error probability analysis is performed for both a conventional and a noise-normalized combining noncoherent M-ary orthogonal frequency shift-keying (MFSK) receiver employing fast frequency-hopped (FFH) spread spectrum waveforms transmitted over a frequency-nonselective, slowly fading Ricean channel with partial-band interference. Each diversity reception is assumed to fade independently. The partial-band interference is modeled as a Gaussian process. The effects of wideband thermal noise are also included. The energy per hop is held constant; thus, as diversity increases, energy per symbol increases. Previous analyses considered only a constant energy per symbol, in which case the noise-normalized receiver results in a significant improvement an performance as compared to the conventional receiver. The difference in performance between the two receivers a constant energy per hop signaling scheme is investigated