Performance of RAKE reception in dense multipath channels:implications of spreading bandwidth and selection diversity order

摘要

We develop an analytical framework to quantify the effects of thenspreading bandwidth (BW) on spread spectrum systems operating in densenmultipath environments in terms of the receiver performance, thenreceiver complexity, and the multipath channel parameters. The focus ofnthe paper is to characterize the symbol error probability (SEP)nperformance of a RAKE receiver tracking the L strongest multipathncomponents in wide-sense stationary uncorrelated scattering (WSSUS)nGaussian channels with frequency-selective fading. Analytical SEPnexpressions of the RAKE receiver are derived in terms of the number ofncombined paths, the spreading BW and the multipath spread of thenchannel. The proposed problem is made analytically tractable byntransforming the physical RAKE paths, which are correlated and ordered,ninto the domain of a “virtual RAKE” receiver withnindependent virtual paths. This results in a simple derivation of thenSEP for a given spreading BW and an arbitrary number of combined paths