Research On OFDM Synchronization Technologies Of The High-rate Data Communication Interface

During recent years, traditional aviation bus can no longer satisfy the requirements of modern military communication, so developing high-rate data communication interface on the original 1553 bus has great significance. High-rate data communication interface is based on OFDM technology, and it provides a data highway which is compatible with existing network. However, high-rate bus system can work correctly only on the premise of precise synchronization.In this dissertation, firstly we introduce the basic principles of OFDM, and then analyze the effect of synchronization deviation on OFDM system. The emphasis is focused on the study of training symbol aided timing estimation method for burst packet transmission system. Three classic timing estimation algorithms are compared. On this basis, a novel training preamble as well as new timing estimation method for OFDM systems is proposed. Simulation results indicate the improved method eliminate the correlation plateau, keeps low complexity, has smaller MSE. In addition, pilot symbol aided sample clock synchronization method is presented and improved, thus compensating amplitude attenuation through AD converter.Finally, we illustrate the Physical Layer standard of high-rate data communication interface, test the channel characteristics. Then the new timing estimation method is applied to this system. Timing synchronization module is designed and implemented on the platform of FPGA. Through test of the module and system, the synchronization algorithm is proved to be stabile and feasible. It is low in complexity and easy to realize. It can save a lot of resources for hardware. Analysis shows that good synchronization performance contributes to the success of IF receiving system.