一种基于迭代交织的任意长度扩频码生成器

摘要

Spreading code design is an important item of China BDS signal structure.It is difficult to meet the requirements of flexible code length and good performance in spreading code design at the same time.Independent intellectual property right is another goal of BDS signal structure.A flexible-length spreading code generator based on interleaving operation and feedback-iterate structure is proposed in this paper.Random sequence is build by the random effect of interleaving operation.The output sequences of iterative operations forms the candidate set of spreading codes.The critical of interleaving operator and seed se-quence selection are discussed also.Four spreading codes families with 1023,2046,4092,10230 bits length are designed by u-sing iterative interleaving generator.The result of evaluation shows that the performance of new code families is equivalent or better than spreading codes of GPS,Galileo and BDS.The new generator can used to design spreading codes with flexible code length and good performance.The iterative interleaving code has the benefit of perfect code balance,low generation complexity and provides a candidate for BDS signal design.%扩频码设计是北斗系统信号体制的重要内容，同时满足码长选择灵活性和良好性能是扩频码设计中的难题，自主知识产权也是北斗信号设计的目标之一。基于交织运算和反馈-迭代结构提出一种适合任意长度的扩频码生成器，利用交织运算的随机化效应产生随机序列，通过反馈-迭代运算产生扩频码候选集合，讨论了交织运算器和种子序列的选择准则。采用迭代交织生成器构造1023、2046、4092、10230比特扩频码方案，评估结果表明，迭代交织扩频码与全球定位系统、欧洲伽利略系统和中国北斗卫星导航系统的扩频码方案相比性能相当或更优。迭代交织生成器可以生成任意长度、性能良好的扩频码方案，同时具有完美平衡性和计算复杂度低的优势，为我国北斗系统信号设计提供了一种候选方案。