The Design And Implementation Of Downlink Physical Layer And API In Edge Base Station System

GSM communication system, called the Global System for Mobile communication, has the world's most users and the most extensive coverage. GSM system is entirely in accordance with the European Telecommunications Standardization Committee (ETSI) to develop the GSM technical specifications. Any GSM digital cellular mobile communication system must meet the GSM specifications.In order to solve the contradiction between not high enough data transfer rate and the growth in demand for new services,3 GPP organization introduced the EDGE program (Enhanced Data Rates for GSM Evolution) GSM solution for enhanced data rate. The program adds 8PSK modulation (8 phase shift keying).8PSK modulated signal carrying 3bit information in EDGE system is 3 times more than the data transfer rate of GSM/GPRS system, the data transfer rate is greatly improved. EDGE is based on the original proposal of GSM/GPRS system and has backward compatibility, so the system does not require large scale replacement of equipment upgrades and save cost of system upgrades to the greatest degree.This paper describes and analyzes the downlink physical layer and Application Program Interface subsystem design and implementation for the base system of EDGE, which is based on the multi-core processors, picoArray. From the overall structure of EDGE to the downlink physical layer modules in EDGE system, this paper made a detailed introduction. The main content of the paper is divided into four parts to introduce the procedures of design and implement of the downlink physical layer and API for the base system of EDGE. First it conducted an overall introduction of EDGE system. The architecture of the downlink physical layer is given. Then picoArray, the multi-core processors, has been introduced. Thirdly, from the perspective of functional design and the implementation process, every module in the downlink physical layer has been defined in detail. Finally, API subsystem has been discussed, which consists of module structure design and implement procedure.