混合信号到达角估计算法研究

发布时间：2018-06-29 23:17

本文选题：空间谱 + 到达角估计　；参考：《天津大学》2014年硕士论文

【摘要】：当前无线通信环境日趋复杂,独立信号和相干信号经常同时存在于无线信道中,而绝大多数现有的到达角估计技术都是只针对独立信号或相干信号进行研究的。在这种情况中,只针对独立信号的到达角估计算法不再适用。只针对相干信号的算法虽仍然有效,但会把独立信号和相干信号一起进行解相干处理,这样会进一步增大天线阵列的阵列孔径损失。同时,独立信号和相干信号之间也会相互干扰,降低算法的估计性能。本文针对混合信号的情况,提出了一种分步估计信号到达角的改进算法。该算法首先利用传统MUSIC算法估计独立信号的到达角,然后在信号协方差矩阵中分离出相干信号的协方差矩阵,只对相干信号进行空间平滑处理,进而估计出相干信号到达角。综合两步的结果,得到混合信号的全部到达角参数。相比传统空间平滑算法,本文算法创新点在于:新算法将独立信号和相干信号分开处理,在保持良好到达角分辨率的同时,避免了阵列孔径的不必要损失,减小了对天线阵列数的要求,在信噪比较低的情况下拥有更精确的估计性能。
[Abstract]:At present, the wireless communication environment is becoming more and more complex, independent signals and coherent signals often exist simultaneously in wireless channels, and most of the existing angle of arrival estimation techniques are only focused on independent signals or coherent signals. In this case, the angle of arrival estimation algorithm for independent signals is no longer applicable. Although the algorithm for coherent signals is still effective, it will decoherently process the independent signals and coherent signals together, which will further increase the array aperture loss of the antenna array. At the same time, the independent signal and coherent signal also interfere with each other, which reduces the estimation performance of the algorithm. In this paper, an improved step-by-step algorithm for estimating the arrival angle of mixed signals is proposed. Firstly, the traditional music algorithm is used to estimate the angle of arrival of the independent signal, then the covariance matrix of the coherent signal is separated from the signal covariance matrix, and only the coherent signal is processed by spatial smoothing, and the angle of arrival of the coherent signal is estimated. All the parameters of the angle of arrival of the mixed signal are obtained by synthesizing the results of the two steps. Compared with the traditional spatial smoothing algorithm, the innovation of this algorithm is that the new algorithm processes the independent signal and the coherent signal separately, while keeping the good angular of arrival resolution and avoiding the unnecessary loss of the array aperture. The requirement of antenna array number is reduced, and the estimation performance is more accurate under the condition of low SNR.
【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】：TN911.23

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