In Td-scdma Physical Layer Simulation And Joint Detection Algorithm

Mobile communication is one of the most brilliant technologies in century 20. From the first anolog cellular system to today's successful second digital system, great developments have been made including technologies, user amounts and service range. The third generation mobile communication (3G) marked by wide-band and multimedia service will come to business soon.This thesis study and compare the modern mobile communication main techniques, including WCDMA, CDMA2000, TD-SCDMA, LAS-CDMA. Focuse on the TDD mode and the new techniques: Joint Detection and Smart Antenna, which bring many merits for TD-SCDMA. We build the platform for simulation of the physical layer in TD-SCDMA, and study the different receiver schemes based on Joint Detection algorithms:(1) First we study wireless physical channels, its mathematical models and ITU models; Then base on the specifications of TD-SCDMA to build the simulation platform, implement the bellowed siginal processing techniques: spreading and scrambling, modulation and demodulation, pulse shape filtering, etc; Research the receiver schemes, convolves Channel Estimation and Joint Detection, then place emphasis on the circular correlator for channel estimator, Zero-Forcing and MMSE algorithms for Joint Detection, through simulations we compare the system performance of different channel parameters and different receive schemes.(2) Research of fast algorithms for Joint Detection. We know that Joint Detection will bring luge computation load, so fast Joint Detection is very important. This thesis derive from block Fourier Transforms, research a new fast algorithm based on fast matrix operations, and prove its time and space complexity both in theory and simulation, which shows this algorithm is valuable in real projects.(4) Time space prcessor. Research the schemes of the combinations for Joint Detection and Smart Antenna, simulate and test two methods for the 2-dimension receivers: spartial diversity and Adaptive Antenna Array combined Joint Detection.