The Evdo System To Receive Fixed-point Simulation And Equalization, The Forward Link

EV-DO, proposed by Qualcomm on the basis of cdma2000, is a new telecom standard aiming at improving packet data transferring. In order to address the characters of bursting, asymmetry, low latency, various Qos Level and large amount of data flow, EV-DO has taken in many new techniques in 3G such as TDM, virtual soft handoff, AMC, HARQ and high-level modulation, rendering the maximum rate of Forward Link to 2.4Mbps. This thesis discussed the principles of rake-receiver and equalizations in EV-DO Forward Link, simulated and analyzed its performance from a point of view of engineering implementation.In the first part of this thesis, some new techniques adopted by EV-DO which are different from cdma2000 and EV-DO forward link physical layer structure are introduced.The second part focuses on the forward link Rake receiver, which includes pilot capturing, channel estimation, combination technique and high-level signal demodulation.The last part discusses the equalization for forward link of EV-DO. As is known, the traditional Rake receiver could not eliminate the multi-path interference, the high-level modulation signal also suffers from ISI through multi-path channel which limits the improvement of receiver performance. Herein, LMMSE and LMS equalizers which are based on MMSE standard are introduced first, and then the key parameters of equalizers are confirmed through the simulation, finally considering the realization complexity of equalizers a new parallel-receiver is given out which uses the Rake receiver and LMS equalizer jointly.