序列捕获的序列核变换方法

在序列扩频、加扰通信系统中，通常采用连续接收信号并进行滑动相关运算的方法，通过搜索相关峰进行序列捕获，需要接收多个完整周期的序列。随着序列周期的加大，一方面需要花费大量的接收端存储资源，另一方面，相关运算的计算开销会呈指数增长，导致很难实时捕获长周期序列。为解决这一问题，提出了一种序列核变换方法，变换后的每个元素均包含有完整的序列信息，实现了序列信息压缩。然后，基于该变换方法将捕获过程分为序列检测和序列捕获两个阶段，只在检测到目标序列后才开始捕获，进一步降低了计算开销。理论分析和仿真验证表明，算法通过牺牲部分低信噪比环境下的捕获成功率换取了计算资源的大量减少，算法可在一个序列周期内快速捕获不同周期的m序列，并且所节省的计算资源随序列周期变大而增多。

Sequential acquisition method based on sequence core transform

The existing sequential acquisition methods search the correlation peak continuously in receiving signals, thus wasting a great deal of calculation resources to search correlation peak in the received signal containing no target sequence. In another case, with the sequence period increasing, the calculation resources perform exponential growth. As a result, the target sequence can be hardly got. In order to reduce the calculation resources, the paper presented a sequence core transform method to acquire the sequence. The method compressed the entire sequence information into the local sequence core, and by this sequence core, the acquiring process was divided into two steps: sequence detection and sequence acquisition. In this process, the calculation resources were reduced because the sequence acquisition only occured in the second step. Furthermore, by using the down-sampling on received signals, the sequence core transform could decrease the sequence amount needed in the acquiring process. The theoretical analysis and simulation results show that, by losing some acquiring performance, the algorithm can reduce the calculation resources to complete acquisition in one sequence period. And the reduced calculation resources increase with the sequence period.