Research On High Speed Spread Spectrum And Design On FPGA

Modern aviation communication environment and objects are increasingly complex. Because of its bandwidth is small, low data rate, the traditional aviation can not meet the needs of a large number of real-time transmission of data. Based on the urgent needs of aviation development, development of high-speed, high reliability of aeronautical communications systems is significant. Possessing a lot of merits such as anti-interference, security and low probability of intercept, Direct Sequence Spread Spectrum (DSSS) Communication has become more and more important and its application can be found in many fields.This project is to design and implement a DBPSK DSSS spread spectrum communication system, which is based on FPGA to implement all-digital base band signal process transceiver. Transmission unit through the "ping-pong structure" processing, high-speed spread spectrum, multi-phase shaping filter, high-speed data interface processing between the FPGA and D/A to complete high-speed data spread spectrum modulation and base band shaping. Receiver unit through the high-speed data interface processing between the A/D and FPGA, rotation transformation, the parallel matched filter structure and other key technology to complete high-speed base-band signal dispreading.First of all, this paper will introduce the development of the spread spectrum technology home and abroad and the basic theory of the DSSS communication system which this project refers to. Then it will tell the analysis,design,simulation and implement of the sending part and receiving part separately. System of technical difficulties is the high-speed data link of spreading and dispreading. This paper also analyzed the content of these two aspects. Finally, this paper introduces the hardware platform and test cases, test results and conclusions are given. In the end, it will give out the summarization and prospects of the whole project.