Research On The Digital Signal Processing Technique Of 802.11a Physical Layer

Digital signal processing is one of the subjects expanding rapidly in the field of information science during the past several decades. Especially with the development of micro-electronics, DSP technology has become more and more application. At present, It has applied extensively in many subjects such as communications, radar, sonar, speech and image processing etc. general speaking, there are 3 ways to implement the digital signal processing algorithms, programming DSP for general purpose, ASIC and DSP chipset with invariable function for special purpose, FPGA that can be programmed by user.On the basis of analysis and research in 802.11a key technology-OFDM (Orthogonal Frequency Division Multiplexing), detailed research in digital signal processing technique has been made in this dissertation. The prototype of transmitter and receiver in the IEEE 802.11a protocol PHY layer have been designed firstly, and then respectively analyse and research the FIR module and FFT module in the OFDM system. On the basis of principle of FIR digital filter, this dissertation discusses the DA (Distribute Arithmetic) used in the FIR design, and analyses the advantage and disadvantage of kings of DA. The implementation of lowpass FIR adopts the parallel DA struct on the basis of 802.11a protocol regulation. Aimed at the features of the FIR filter symmetry and look-table datum redundancy, this dissertation adopts arithmetics of the pre-adder and compressing the look-table datum.The implementation of 64 points FFT has been rearched in the dissertation, included of kinds of FFT arithmetics feature. Especially aimed at the feature of 64 points FFT, emphases research and analysis the radix-2 arithmetic, radix-4 arithmetic and split radix arithmetic. This dissertation adopts a new multipath pipeline frame.