Performance evaluation of RAKE receiver for cellular CDMA systems

The paper presents closed form expressions for calculating the performance of a practical RAKE receiver. To solve the statistical problem encountered when deriving the performance, the pdf of Z_L was first derived, which was defined as the sum of the largest μ samples among L identically and exponentially distributed random variables, by invoking order statistics. Using the pdf of Z_L, the average BER of the power controlled single cell CDMA system was obtained The results show that the performance improves as the number of PN correlators, μ increases. However as the number of μ increases one by one, the performance improvement becomes narrower and narrower. Finally, we can also find that performance improves as the number of resolvable paths of channel increases at the same fixed number of correlators