多点定位系统高精度TOA提取方法

针对相关法检测报头时较低的采样频率对获取信号到达时间精度的不利影响，提出 一种基于改进相关法的局部高速采样的高精度TOA提取方法。该方法根据曼切斯特编码特性 在报头后第一个数据位时间内高频采样，使用两级移位寄存器作异或处理检测跳变沿提取到 达时间信息，使测时精度达到了纳秒级，在使用GPS秒脉冲对双接收通道时间进行精确同步 的 基础上，输出提取的时间信息，对比测时的一致性。实验结果表明在实际应用中，TOA测量 精度达到了理论预期。

High-accuracy TOA extraction method in multilateration

A method for extracting high accuracy TOA(Time of Arrival) with local high fre quency sa mpling based on improved correlation method is proposed in this paper for the ad verse effects on the accuracy of extracting TOA in correlation detection with lo w sampling frequency. High frequency sampling is done in the time of one d ata bit after the preamble according to the feature of Manchester encoding. The samples are stored in two shift registers for XOR treatment to detect the edge o f signal, which is the time to extract the TOA. The accuracy of TOA can reach na nosecond level on the basis of precise time synchronization. An experiment with two rece iving channels is performed to verify the accuracy class. The statistical result s show that the TOA measured accuracy has achieved the theoretical prospect in t he practical application.