The performance of diversity combining for fast frequency hopped NCMFSK in Rayleigh fading

Abstract

Frequency hopping (FH) spread spectrum is a well known technique used in communications systems to provide protection against interference such as jamming. With fast FH (FFH) (one or more hops per transmitted data symbol), powerful and robust methods for diversity combining have been developed as an additional jamming countermeasure. These same techniques can be applied to reduce the effects of multiple access interference, and so can be considered for civilian CDMA applications. Although the performance of a FFH communications system can be degraded considerably by fading, few results exist which show the effects of fading on the diversity combining process. In this paper, both analytic and simulation results are presented for several diversity combining methods in a Rayleigh fading channel, which is often considered to be the worst case. The performance of these combining methods in fading is compared with that in AWGN and multitone interference to determine which methods are effective against these degradations. (1) This work was supported in part by the Natural Sciences and Engineering Research Council of Canada. V01.6, NO. 1 J a~~~a~y -F e b m~y 1995

Performance analyses of fast frequency-hopped communication systems against multitone jamming and multiple-access interference

“…where a 1 is the time-average power of the received signal. Rayleigh-fading channels have been widely considered in [13]- [15], [34]- [35], [37]- [38], and the references therein. A detailed survey on the characterization of Rayleigh fading channels for mobile digital communication systems was given in [34] and [35].…”

“…al. focused on the noncoherent FFH/MFSK system and examined the BER performance with several diversity-combining methods over the Rayleigh fading channel [37]. The characteristic functions of the square-law detector outputs have been used to obtain a computationally efficient BER expression for different diversity levels.…”

Interference suppression for fast frequency-hopped communication systems over fading channels

“…For some diversity-combining techniques, side information is required. In the literature, the most commonly used diversity-combining receivers are linear-combining receiver [19], product-combining receiver [20], clipper receiver [21], self-normalizing receiver [22], ratio-threshold test diversity-combining receiver [23], order statistics normalizing receiver [24], hard-limited linear-combining receiver [25], maximum-likelihood receiver [26], etc. In the subsequent sections, we will discuss some of these typical diversity-combining receivers in detail.…”

“…Analytical BER expressions of the order statistics normalizing receiver were presented in [24] for FFH/MFSK systems over frequency non-selective Rayleigh-fading channels with PBNJ. In [62] and [63], the authors studied the system performance of this type of receivers in the presence of MTJ.…”

“…BER performance of the FFH/BFSK product-combining receiver over non-fading channels and frequency non-selective Rician-fading channels with MTJ was studied in [42] and [43], respectively. Performance comparisons among several diversity-combining techniques were presented in [92] for FFH/MFSK systems over frequency non-selective Rayleigh-fading channels with MTJ and AWGN. The ML receiver was proposed to counteract PBNJ and MTJ under non-fading channel conditions in [26] and [50], respectively.…”