Abstract:When interferometric SAR is used to measure the terrain elevation, the dense interference fringes in the complex terrain will lead to phase unwrapping failure, so that the terrain elevation information can not be obtained accurately. In this paper, a new method to reduce the error rate of phase unwrapping is proposed. The interference fringe gradient is decreased by increasing the size of the interference complex image, and the difficulties of phase filtering and phase unwrapping is reduced. Based on the relationship between the complex image frequency and the Nyquist frequency, the adaptability of the proposed method to the terrain is analyzed. The effectiveness of the proposed method is verified by theoretical analysis and simulation. Especially for the large gradient region conforming Nyquist sampling, this method has good filtering and unwrapping effect. The method proposed does not need extra data, is simple to implement and fast in operation, and can be applied to the ground processing system of interferometric SAR.
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