基于单比特信号的互相关算法研究

发布时间：2018-01-16 03:14

本文关键词：基于单比特信号的互相关算法研究　出处：《哈尔滨理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：互相关法在雷达、GPS等测距和定位领域的应用十分广泛,但传统的互相关算法运算量较大,需要高成本的数字信号处理能力。本文采用一种新的互相关算法,将超声波模拟信号经过比较器转换为单比特信号进行互相关运算,显著减少了运算量,同时也降低了对硬件的要求。针对超声波测距系统,通过分析传统互相关算法的运算过程,找出导致脉冲压缩信号互相关运算量大的主要因素,有针对性地采取措施,即采用单比特信号处理方法来减小算法的运算量。该方法原理是将原脉冲信号通过比较器进行量化,从而得到单比特信号,单比特信号在互相关运算中卷积运算可由逻辑运算来代替,单比特信号使离散傅里叶变换DFT中的输入信号与核函数的乘积相加运算变成只有加法运算,这可以使互相关运算量显著降低。此外,信号在介质传播过程中混有噪声而影响测量精度,互相关计算过程中必须进行去噪运算,这需要研究单比特滤波算法及其运算时间,本文针对高频震荡系统采用滑动平均滤波进行去噪处理,研究了单比特信号滤波算法的去噪效果及其运算时间。采用MATLAB针对单比特信号的互相关运算和多比特信号的互相关运算进行仿真实验对比、针对滑动平均滤波单比特信号去噪算法进行仿真实验。通过理论分析和仿真对比实验,验证单比特信号互相关算法的正确性和有效性,验证滑动平均滤波单比特信号去噪算法的去噪效果和运算时间。
[Abstract]:The cross-correlation method is widely used in radar and GPS ranging and positioning fields, but the traditional cross-correlation algorithm has a large amount of computation. In this paper, a new cross-correlation algorithm is used to transform the ultrasonic analog signal into a single bit signal by a comparator for cross-correlation operation, which can significantly reduce the amount of computation. At the same time, it also reduces the requirement of hardware. According to the ultrasonic ranging system, by analyzing the operation process of the traditional cross-correlation algorithm, we find out the main factors that lead to the large cross-correlation operation of the pulse compression signal. Some measures are taken, that is, the single bit signal processing method is adopted to reduce the computational cost of the algorithm. The principle of this method is to quantize the original pulse signal through the comparator, and thus to obtain the single bit signal. The convolution operation of single bit signal in cross correlation operation can be replaced by logical operation. Single bit signal makes the product addition of input signal and kernel function in discrete Fourier transform (DFT) into only addition operation. In addition, the signal is mixed with noise in the process of medium propagation, which affects the measurement accuracy, and the de-noising operation must be carried out in the process of cross-correlation calculation. This need to study the single bit filter algorithm and its operation time, this paper used moving average filter for high-frequency oscillation system to remove noise. The de-noising effect of single-bit signal filtering algorithm and its operation time are studied. The cross-correlation operation of single-bit signal and the cross-correlation operation of multi-bit signal are simulated and compared with each other by MATLAB. Simulation experiments are carried out for moving average filter single bit signal denoising algorithm. The correctness and effectiveness of single bit signal cross-correlation algorithm are verified by theoretical analysis and simulation and comparison experiments. The denoising effect and operation time of moving average filter single bit signal de-noising algorithm are verified.
【学位授予单位】：哈尔滨理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB559;TN713

【引证文献】