The Design And Implementation Of The Baseband Processor Of WiMAX System

WiMAX(Worldwide Interoperability for Microwave Access), as a emerging broadband wireless access scheme for WMAN (Wireless Metropolitan Area Networks), is able to provide a better mobility in the application of high-speed data. WiMAX technology includes the fix and mobile access and contains two standards: IEEE802.16d (IEEE802.16-2004) and IEEE802.16e (IEEE802.16-2005). The article is the study of the baseband processor of WiMAX system, based on IEE802.16d.Firstly, the article introduces the wireless broadband access with a brief presentation. Then it fetches out the goal of the article: WiMAX and narrates the WiMAX standard and technology features. Then it makes a theoretical analysis and annotations on the orthogonal frequency division multiplexing (OFDM), which is IEEE802.16's basic.Currently, a lot of theoretical research is made for WiMAX technology, but its hardware implementation is less discussed. In this instance, WiMAX baseband processor, based on the IEEE 802.16, is studied in this paper, focusing on its universal programming hardware platform design. The entire system uses CPU + DSP + FPGA structure, the greatest feature is its flexible structure, suitable for modular design, which can increase algorithm efficiency. At the same time it shortens development cycle and the system is easy to maintain and expand, suitable for real-time signal processing.Afterwards it focuses on FPGA-based baseband processor interface logic, an important part of the baseband processor system. IP is used to realize OFDM modulation / demodulation requirement and given an efficient implement structure based on FPGA, which is occupied less resources, and high efficiency. In order to meet the demand of base station transmission, the thesis introduces the CPRI protocol to achieve data transmission by compare. And its characteristics and realization are detailed analyzed, including the CPRI control pathway-HDLC.