Fpga Implementation Of The Frame Synchronization Algorithm In OFDM System Receiver

OFDM (Orthogonal Frequency Division Multiplexing) technology with high spectralefficiency, the capability of anti-multipath fading, being able to effectively combatinter-symbol interference, and many other prominent advantages,has been widely used inbroadband wireless access systems, and as the key technology of the future mobilecommunication systems, it becomes the research hotspot of today’s wireless communicationsfield. However, due to the OFDM system is sensitive to the time and frequencysynchronization errors,small synchronization error will cause great deterioration of systemperformance, and even unable to implement the communication. Therefore, thesynchronization performance has a directly impact on the performance of OFDM broadbandwireless data transmission system. This article is mainly for synchronization in OFDMsystems and its FPGA implementation.This article briefly describes the development and current situation of the OFDMtechnology, elaborates the basic principles of OFDM technology, features and technicaladvantages in detail. And it analyzes the radio channel propagation characteristics and thechannel model of this simulation. The article studied the synchronization algorithm based onthe data-aided algorithm, on the basis of the classical algorithm, proposes an OFDMsynchronization algorithm based on CHU sequence, and the simulation is using MATLABtools. According to the simulation results, the synchronization algorithm that is furtheroptimized can be reduced nearly half of the multiplication, making the hardwareimplementation is more straightforward. In the end, using production of Xilinx’s Spartan-3EFPGA development board as the hardware platform, design synchronization algorithms. Themain work of the paper is as follows:(1) Use the MATLAB tool to simulate of the whole OFDM transmission system, analysisof the OFDM system transceiver and set up the OFDM equivalent baseband system.(2) On the basis of the classical algorithm, propose the OFDM frame timingsynchronization algorithm with high synchronization performance based on the CHU sequence and do the simulation. Design a new header structure and the timing metric functionto complete the frame synchronization detection. The simulation result shows that thisalgorithm can achieve the synchronization requirements of the system in low signal to noiseratio and multipath fading channel.(3) Based on the above simulation results, the synchronization algorithm is furtheroptimized, just taking the real part of timing metric function. Using MATLAB to do the10,000Monte Carlo simulation, the simulation results show that the timing position iscompletely accurate, and can save nearly half of the resources occupied. Based on thesimilarity between optimized timing metric function and the FIR filter defined formula, usethe Xilinx FIR complier IP core to complete the synchronization algorithm designed,makingthe synchronization algorithm realization much simpler to realize.