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A Range and Velocity Ambiguity Resolution Method Based on Ambiguity Matrix Completion and Elimination with Low SNR

In space-borne surveillance radar, the medium pulse repetition frequency (MPRF) is preferred to avoid the transmit pulse eclipsing in range domain meanwhile to obtain a large unambiguous Doppler detectable zones, especially for ultra-high speed targets. However, there exist great challenges in acquiring the unambiguous information of targets due to the serious range and velocity ambiguity. In this paper, a new method is proposed to resolve two-dimensional (2D) ambiguity and suppress the ghosts simultaneously. Firstly, a 2D ambiguity matrix consists of all the possible range and velocity information from multiple PRFs is constructed. The element of this matrix is calculated by counting the target number located in the same position. Secondly, the element value related to detected target will be replaced by the updating strategy. Then the accurate range and velocity information can be obtained by calculating the mean range-Doppler value measured from different PRFs. The numerical results show that the proposed algorithm has a lower computation complexity with less ghosts in low-SNR case compared to the 1D clustering method.