The effects of phase estimation errors on RAKE receiver performance

As larger diversity and coding gains are introduced into spread-spectrum systems to mitigate the effects of multipath fading and thermal noise, system performance is increasingly being limited by channel estimation error. To properly design these systems, performance measures incorporating the effects of estimation errors are needed. A lower bound on the probability of bit error for a RAKE receiver operating with imperfect phase estimates is presented along with a method to obtain a closed-form expression for its evaluation. Further, this lower bound is compared to an upper bound so that an accurate assessment of system performance can be obtained.