调频连续波激光测距系统及其信号处理算法研究

发布时间：2018-01-11 04:03

本文关键词：调频连续波激光测距系统及其信号处理算法研究　出处：《天津大学》2014年硕士论文　论文类型：学位论文

【摘要】：实时、大范围、高精度现场测量成为大尺寸测量的重要发展趋势,调频连续波激光测距是一种新型的激光测距方法,可以进行无合作目标的非接触测量,其测距范围大、精度高、分辨率高,相比其他激光测距方法具有显著的优势,在大尺寸高精度工业测量中拥有着广阔的应用前景。对调频连续波激光测距系统及其信号处理的研究,对于提高系统的测距精度、分辨率和测量范围具有十分重要的意义。本文首先对调频连续波激光测距系统的信号处理算法的国内外研究现状进行了总结,发现相关课题组对调频连续波激光测距中激光器的频率调制线性度及频率扫描范围对测距精度的影响的研究较少。明确了本文将研究通过信号处理算法减小调频连续波激光测距的激光器的非线性调制对测距精度的影响,突破激光器频率扫描范围的限制,减小频率测量时的误差。本文提出了一种通过增加辅助干涉光路对测量信号进行等频率间隔的采样、然后对采样信号进行拼接,最后对频率测量进行校正的方法来提高调频连续波激光测距系统的测距分辨率和精度的方法。设计搭建了一种双干涉系统的光纤调频连续波激光测距系统,利用辅助干涉系统产生的时钟信号对测量干涉系统的信号进行等光频间隔采样,然后对采样的拍频信号进行拼接,最后对测得的频率进行校正,从而得到目标的距离。使用LabVIEW设计实现了信号错误检测处理、等频率间隔采样、拼接和频率校正的信号处理系统。理论和实验验证了将等光频间隔的采样信号进行拼接的方法可以突破激光器扫描范围的限制,减少光源非线性的影响,从而提高系统的测距分辨率。实验结果表明,调频连续波激光测距系统采用的信号处理算法可以提高调频连续波激光测距系统的测距精度和分辨率。对测量目标分别进行了8.7米和14.2米的测距实验以及测距分辨率的实验,证明了测距系统所采用的信号处理算法的测距分辨率可达70?m,接近于理论值,并且具有较高的测距稳定性,可以实现远距离的高精度测量。
[Abstract]:Real-time, large-scale, high-precision field measurement has become an important development trend of large-scale measurement. FM CW laser ranging is a new laser ranging method, which can be used for non-contact measurement without cooperative targets. It has a large range of ranging, high accuracy, high resolution, and has significant advantages over other laser ranging methods. The research on FM CW laser ranging system and its signal processing can improve the range accuracy of the system. The resolution and measurement range are of great significance. Firstly, this paper summarizes the research status of signal processing algorithms of FM CW laser ranging system at home and abroad. It is found that the influence of frequency modulation linearity and frequency scanning range on ranging accuracy in frequency modulated CW laser ranging is less studied by related research group. It is clear that this paper will reduce frequency modulation by signal processing algorithm. The influence of nonlinear modulation of CW laser ranging on ranging accuracy. By breaking through the limit of laser frequency scanning range and reducing the error in frequency measurement, a sampling method with equal frequency interval by increasing the auxiliary interference light path is proposed in this paper. Then the sampling signal is spliced. Finally, the method of correcting the frequency measurement to improve the resolution and precision of the frequency modulation CW laser ranging system is proposed. A double-interference system based on fiber frequency modulation CW laser ranging system is designed and built. The clock signal generated by the auxiliary interference system is used to sample the signal of the measuring interference system with equal optical frequency interval, then the sampled beat frequency signal is spliced together, and the measured frequency is corrected. In order to get the distance of the target, the signal error detection processing is realized by using LabVIEW design, and the sampling at equal frequency interval is realized. Signal processing system of splicing and frequency correction. Theoretical and experimental results show that the method of splicing the sampling signals with equal optical frequency interval can break the limit of laser scanning range and reduce the nonlinear influence of light source. In order to improve the range resolution of the system, the experimental results show that. The signal processing algorithm used in the FM CW laser ranging system can improve the ranging accuracy and resolution of the FM CW laser ranging system. The ranging experiments of 8.7 and 14.2 meters for the target are carried out, respectively. And ranging resolution experiments. It is proved that the range resolution of the signal processing algorithm used in the ranging system can reach 70? M, which is close to the theoretical value, and has high ranging stability, which can realize high precision measurement in long distance.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TH744.5;TN911.7

【相似文献】