Research On CDMA2000 Reverse Link Channel Estimation Technology And Simulation

Mobile communication has been developed dramatically in recent years. Therelevant technologies play a very important role in human life and societydevelopment. Because of its excellent features such as high system capacity, goodquality of voice, strong resistibility for interference and soft hand-off, The Codedivision Multiple Access (CDMA) technology has been selected as a core technologyfor new generation (3G) mobile communication more attention to the internationalcompanies and manufactures pay more attention to the research and development ofCDMA system.It is a basic requirement that the 3G mobile communication system shouldsupport voice, data traffic and their combinations with less expense. Cdma2000 is onof the most competitive candidates for the 3Gmobile communication system .it isbasic form, named cdma2000-1X.is an improved version of IS-95A .It inherits keytechniques of IS-95A and is compatible with IS-95CDMA system, but with someextinction so as to support high rate data transmission and mobile Internet services. Inthis thesis, investigations are conducted on cdma2000 reverse link, including thecomparison IS-95Aand cdma2000-1x, with regard to spreading, modulation,variable-rate transmission, forward error correction and random access method andothers.This thesis also provides both theoretical studies and computer simulation ofRAKE receiver in CDMA communication system. We introduce the principles at first,and give structure of RAKE receiver using optimized channel estimation. Than acoherent RAKE receiver model using pilot signal for channel estimation .is presentedfor cema2000 reverse link. A novel method, which dynamically adjusts mean lengthof channel estimation, is proposed. As a result, the estimation error is eliminated andperformance of RAKE receiver is improved.Finally, computer simulation tools named System View is introduced and detailedcomputer simulation results are presented and discussed for the cdma2000 reverselink, some suggestions are made for selecting different parameters and relevantperformance is verified by computer simulations.