基于TDDM调制方式的sin-BOC信号精确捕获算法

针对时分数据调制(time division data modulation,TDDM)的正弦型二进制偏移载波(binary offset carrier,BOC)自相关函数多峰性导致的无法精确捕获的问题,提出了一种基于子相关函数组成的相关函数捕获算法。该算法通过接收信号和调制过的本地伪码分别与本地TDDM BOC信号子载波的每一个码片相关,根据两种相关函数之间的对应关系,合成一种精确的无模糊捕获算法,并详细介绍了捕获算法原理。理论和计算机仿真表明,该算法运算复杂度低,而且完全消除了副峰,在同一条件下,主峰峰值能量相对于相关重构算法提高了79.5%。

Accurate acquisition method of sin-BOC signal based on TDDM modulation

For the problem of ambiguous acquisition of sin-BOC (binary offset carrier) based on time division data modulation (TDDM), a method which is based on correlation function of sub-correlation is proposed. The method is related to each chip of the local TDDM-BOC signal subcarrier by received signals and the local pseudo code which is modulated. According to the correspondence between two correlation functions, an exact unambiguous acquisition algorithm is synthesized, and the principle of the acquisition algorithm is introduced in detail. Theoretical analysis and computer simulations show that the algorithm not only has lower complexity, but also completely eliminates secondary peak. Under the same conditions, its peak energy of the main peak increases by 79.5% than that of the correlation reconstruction algorithm.