結合直序展頻與糾錯編碼技術之研究

Abstract

擴展頻譜通訊（Spread Spectrum Communication-SSC）技術簡稱展頻技術，具有抗干擾強，抗多重路徑衰減好，保密性好等一系列的優點，在軍事通訊中得到應用與發展。近年來，直序展頻系統DS-CDMA在碼分多址 (CDMA) 等民用通訊中的應用也開始越來越受到人們的重視。另一方面，任何實際系統的通道都是有干擾的, 通道雜訊會影響通訊的可靠性。 提高通訊系統可靠性常用方法之一是採用錯誤更正碼技術。本文在分析直序展頻系統DS-CDMA的研究背景，發展現狀與意義的基礎上，利用錯誤更正碼技術實現在保證通訊系統的通訊容量的同時盡可能提高通訊的可靠性。研究了一種將M元展頻和錯誤更正碼相結合的通訊方案，詳細分析了系統的原理與實現，分析結果表明：它不僅在帶限通道中獲得了較高的資料傳輸速率，同時採用糾錯編碼增強了系統的可靠性。

Spread Spectrum Communcation (SSC) technology has the characteristic of high secrecy, and robustness to noise and multipath decay, and it has wide application in military communication. In recent years, the application of the direct sequence spread spectrum technology in code division multiple addresses (CDMA) has attracted increasing interests among the researches. On the other hand, there are noises in any practical channel, which can reduce the reliability of the communication. One of the approaches in improving the reliability of the communication system is to use the error correcting coding technology. Based on the investigation on the background and the development on the discrete sequence spread spectrum technology, we use the error correcting coding technology to improve the security and the system capacity. In the paper we discussed a realization of communication system by combing M-ary spread spectrum with error correcting coding technology. The analyzing results show that it can not only obtain higher data transmitted rate, but also improve the reliability of the system by error correcting coding strategy.