基于Walsh变换的GPS C/A码快速捕获算法  

The Fast GPS C/A Code Acquisition Algorithm Based on Walsh Transform

作　　者：李仰志[1] 程剑[1] 吕晶[1] 李广侠[1] 李志强[1] 

机构地区：[1]解放军理工大学通信工程学院卫星通信重点实验室,江苏南京210007

出　　处：《电子学报》2011年第6期1384-1388,共5页Acta Electronica Sinica

基　　金：国家高技术研究发展计划(863计划)课题(No.2008AA12Z307);国家自然科学基金(No.61032004)

摘　　要：根据m序列的相移组合多项式,给出Walsh序列与m序列行对应关系的计算方法.利用Walsh序列与Gold序列的映射关系,提出利用移位相加电路减小矩阵运算量的方法,解决Gold序列的快速相关运算问题.采用连续帧相关的方法,消除导航信号符号跳变对相关运算的影响,同时,针对GPS卫星码字的特点,提出了一种多星捕获方法,利用第一颗卫星的捕获运算结果,减小后续卫星捕获的计算量.The relationship between the rows of Walsh and m sequence matrix is presented depending on the polynomial produce phase shift of m sequence.By using a mapping relation between Gold sequences and Walsh sequences,a fast algorithm is proposed to deal with the problems lying in fast correlation of Gold sequence.The algorithm utilizes the shift accumulator to reduce the computation cost.A consecutive frame correlation method is investigated to solve the influence of data bit transition on correlation.A multi-satellite code acquisition method is presented according to the characteristic of the GPS C/A codes,which reduces the calculation operation of the subsequent satellite acquisition based on the acquisition result of the first satellite code.

关 键 词：捕获 快速Walsh变换 GPSC/A码 

分 类 号：TN967.1[电子电信—信号与信息处理]