Td-scdma Base Station Side Of The Hsdpa Mac Design And Implementation

As the fast development of communications and information technology the demand of the downlink data service of mobile network is increasing tremendously. The 2Mbps peak speed of single frequency TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) data transportation became unable to satisfy some new data services. In this context, the multi-frequency HSDPA (High Speed Downlink Packet Access) is proposed by 3GPP in Release 5 specification.To satisfy the demand of unsymmetrical downlink packet data service, the multi-frequency HSDPA implements the MAC-hs entity into Node B. This dissertation is focus on discussing the design and implementing of the key algorithms of flow control, scheduling & priority handling and HARQ.This dissertation investigates the 3GPP module of TD-SCDMA system, analyzes the mechanism of flow control in HSDPA MAC in detail, and proposes a suitable method, which has low transport lag and low signaling cost. Furthermore, based on the thought of the Proportional Fairness Algorithm, the dissertation proposes a way to solve the problem of how to determine the priority of the HSDPA user, which proves to be practicable. In addition, the dissertation puts forward a way to implement HARQ entity based on the requirement of 3GPP R5 specification. By investigating some existed HSDPA technology documents, the dissertation raises a way to allocate the power that is a limited resource in Node B and proposes ways to determine the allocation of physical resources, the redundancy version and the way to calculate Nir.After discussing the key technologies of the MAC-hs, the dissertation is focused on how to implement the algorithms on TD-SCDMA Node B system. The dissertation gives a structure of the multi-frequency HSDPA MAC system. It discusses the methods and procedures of each function unit. Furthermore, according to the system structure of Node B, it proposes the definitions and procedures of the interfaces between HSDPA MAC system and other systems on Node B.In the end of the dissertation, it tests and verifies the feasibility of the designed system, and gives us a satisfying result.