Summary: | 碩士 === 國立臺灣大學 === 電信工程學研究所 === 87 === Recently, bearing estimation using signal cyclostationarity
has been a new topic of great interest. By given the cycle frequency of the signals of interest, we can easily achieve
signal-selective bearing estimation without other distinctive attributes.
In this thesis, we mainly study the problems of bearing estimation using signal cyclostationarity in some nonideal conditions. At first, we consider the bearing estimation problem due to cycle frequency error. We observe that the performance of bearing estimation using signal cyclostationarity
will severely deteriorate even if there exists a small mismatch between the presumed and actual cycle frequencies. Several methods are then presented to alleviate the performance degradation due to the cycle frequency error.
On the other hand, we also consider the bearing estimation problem for cyclostationary signals when the sensor location is randomly perturbed.By restoring the inherent properties of the cyclic correlation matrices for a uniform linear array, the effect of the sensor position error on array performance can be reduced.
Finally, the bearing estimation problem in the presence of near-field cyclostationary sources is discussed. In conjunction with the FFA algorithm, we present a new bearing estimation method to effectively find the directions of these near-field cyclostationary signals.
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