| Today, the Third Generation (3G) mobile tele-communication system is coming into commercial application, and the key technology is Radio Access Technology. WCDMA (3GPP FDD) which is one of the three important Radio Access Technologies introduced HSDPA (High Speed Downlink Packet Access) feature in its R5. HSDPA can give higher throughput and peak rate, and less delay, basing on Adaptive Modulation and Coding (AMC) and Hybrid ARQ (HARQ).This paper introduces how to construct the downlink simulation program of HSDPA (using MATLAB), and studies the downlink of HSDPA using this program. At first, this paper analyse the coding process of HSDPA downlink physical channels which will be implemented in simulation program using MATLAB. And then, this paper studies the relative algorithms of coding and decoding of HS-DSCH and HS-SCCH,and give the algorithms in MATLAB. Then, the study of performance of HS-DSCH is given, which is studied by BLER vs SNR under different MCS. And this is the base of AMC scheduling algorithms. In the last, this paper study the selection of redundancy version of HARQ function using this simulation program, and an optimized scheduling algorithm of the selection of HARQ function is introduced basing on the results of simulation.The simulation of this paper is directive in development and research of HSDPA system. And the performance of HS-DSCH and the optimized scheduling algorithm of the selection of HARQ function can be use in real system directly. |
