多项式相位信号时差估计方法
发布时间：2018-12-28 19:51
【摘要】：随着现代通信行业的飞速发展,无线定位技术渗透到了我们日常生活的方方面面。通信服务、定位追踪、信息安全等正成为当今无线定位技术的重要发展方向并愈发影响和改变着人类的工作和生活。无线定位技术本质是通过对基站与移动站之间传输信号的某一个或多个特征参数制定对应的算法来实现对于位置坐标的估计与获取。AOA、TOA、SOA、TDOA定位方法构成各自的定位体系,其中TDOA以其独特的优势得到了越来越多的重视。而在很多现实应用中,许多信号往往为非平稳信号,且其相位也具有连续特性,那么常用的广义互相关等基于平稳特性信号的方法将不再适用。现代信号处理中广泛涵盖的非线性、非平稳问题中信号模型都可以用多项式相位信号来近似。本文主要针对多项式相位信号的时差估计问题,基于不同阶数的多项式相位信号时差估计进行算法研究。主要内容有:1.研究了基于循环相关矩方法,将其幅度以及相位信息应用于线性调频信号时差估计方法,与传统广义互相关时差估计方法进行了比较,明确了其对于处理非平稳信号时差问题的优势。2.研究了分数阶傅里叶变换(FrFT)及基于FrFT的单分量/多分量线性调频信号时差估计方法,并仿真验证了其较好的估计性能。3.针对FrFT存在的伪峰干扰问题,引入了线性变换得到简化分数阶傅里叶变换消除伪峰干扰并应用于单分量/多分量线性调频信号时差估计中,与传统广义互相关方法进行了仿真比较并验证了其在各种信号环境中的良好估计性能。4.提出了基于SFFT的线性调频信号快速时差估计,利用预判法大幅度减小了二维搜索范围从而降低了计算量。通过仿真比较了其与常规方法以及GCC方法估计效果,验证了其在低信噪比环境下的良好估计性能。5.针对三阶相位信号引入了信号的瞬时相关量将相位降为二阶再利用上述二阶相关方法进行常规估计和快速估计,提取时差信息。仿真比较了其与传统广义互相关估计方法的效果,验证了瞬时相关量对于处理三阶相位信号时差问题的有效性和相关算法的稳健性。
[Abstract]:With the rapid development of modern communication industry, wireless positioning technology permeates every aspect of our daily life. Communication services, location tracking, information security and so on are becoming the important development direction of wireless location technology and increasingly affecting and changing the work and life of human beings. The essence of wireless location technology is to estimate and obtain the position coordinates by making corresponding algorithm for one or more characteristic parameters of the signal transmitted between the base station and the mobile station. AOA,TOA,SOA, TDOA positioning methods constitute their respective positioning systems, in which TDOA has been paid more and more attention for its unique advantages. However, in many practical applications, many signals are often non-stationary signals, and their phases also have continuous characteristics, so the commonly used methods based on stationary signals such as generalized cross-correlation will no longer be applicable. In modern signal processing, nonlinear and nonstationary signal models can be approximated by polynomial phase signals. In this paper, the time difference estimation of polynomial phase signal is studied based on the different order of polynomial phase signal. The main contents are: 1. Based on the cyclic correlation moment method, the amplitude and phase information is applied to the time difference estimation of LFM signals, which is compared with the traditional generalized cross-correlation time difference estimation method. The advantages of this method in dealing with the non-stationary signal moveout problem are clarified. 2. The method of time difference estimation for single-component / multi-component LFM signals based on fractional Fourier transform (FrFT) and FrFT is studied. In order to solve the problem of pseudo peak interference in FrFT, the simplified fractional Fourier transform is introduced to eliminate the pseudo peak interference and is applied to the time difference estimation of single / multi-component LFM signals. The simulation results are compared with those of the traditional generalized cross-correlation method and its good estimation performance in various signal environments is verified. 4. The fast time difference estimation of LFM signal based on SFFT is presented. The 2-D search range is greatly reduced by using the prejudgment method and the computational complexity is reduced. The performance of the proposed method is compared with that of the conventional method and the GCC method by simulation, and its good performance is verified in low SNR environment. For the third order phase signal, the instantaneous correlation is introduced to reduce the phase to the second order and then the conventional and fast estimation is carried out by using the second-order correlation method mentioned above, and the time difference information is extracted. The simulation results show that the instantaneous correlation is effective and robust in dealing with the third order phase signal time difference problem.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN911.23
，
本文编号：2394360
[Abstract]:With the rapid development of modern communication industry, wireless positioning technology permeates every aspect of our daily life. Communication services, location tracking, information security and so on are becoming the important development direction of wireless location technology and increasingly affecting and changing the work and life of human beings. The essence of wireless location technology is to estimate and obtain the position coordinates by making corresponding algorithm for one or more characteristic parameters of the signal transmitted between the base station and the mobile station. AOA,TOA,SOA, TDOA positioning methods constitute their respective positioning systems, in which TDOA has been paid more and more attention for its unique advantages. However, in many practical applications, many signals are often non-stationary signals, and their phases also have continuous characteristics, so the commonly used methods based on stationary signals such as generalized cross-correlation will no longer be applicable. In modern signal processing, nonlinear and nonstationary signal models can be approximated by polynomial phase signals. In this paper, the time difference estimation of polynomial phase signal is studied based on the different order of polynomial phase signal. The main contents are: 1. Based on the cyclic correlation moment method, the amplitude and phase information is applied to the time difference estimation of LFM signals, which is compared with the traditional generalized cross-correlation time difference estimation method. The advantages of this method in dealing with the non-stationary signal moveout problem are clarified. 2. The method of time difference estimation for single-component / multi-component LFM signals based on fractional Fourier transform (FrFT) and FrFT is studied. In order to solve the problem of pseudo peak interference in FrFT, the simplified fractional Fourier transform is introduced to eliminate the pseudo peak interference and is applied to the time difference estimation of single / multi-component LFM signals. The simulation results are compared with those of the traditional generalized cross-correlation method and its good estimation performance in various signal environments is verified. 4. The fast time difference estimation of LFM signal based on SFFT is presented. The 2-D search range is greatly reduced by using the prejudgment method and the computational complexity is reduced. The performance of the proposed method is compared with that of the conventional method and the GCC method by simulation, and its good performance is verified in low SNR environment. For the third order phase signal, the instantaneous correlation is introduced to reduce the phase to the second order and then the conventional and fast estimation is carried out by using the second-order correlation method mentioned above, and the time difference information is extracted. The simulation results show that the instantaneous correlation is effective and robust in dealing with the third order phase signal time difference problem.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN911.23
，
本文编号：2394360
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