SOFT-LIMITER RAKE RECEIVERS FOR CODED DS DPSK SYSTEMS OVER PULSE JAMMED MULTIPATH-FADING CHANNELS/

Two soft-limiter RAKE receivers are evaluated for coded direct-sequenc e/differential phase shift keying (DS/DPSK) signaling: over a pulse ja mmed multipath-fading channel that use a combination of antenna and mu ltipath diversity. One uses predetection selective (antenna) combining followed by postdetection equal gain (multipath) combining, and the o ther uses postdetection equal gain combining only. In either case, the postdetection diversity combiner output is soft-limited prior to deco ding, It is shown that for increasing levels of diversity the soft-lim iter becomes quite effective, resulting in a receiver performance that approaches a maximum likelihood (ML) soft decision receiver with perf ect jammer state information.