Abstract: Due to the ambiguities in Direction Of Arrival (DOA) estimation for an interferometric array VHF radar, a novel ambiguity-resolution algorithm based on matrix completion is proposed. The algorithm with additional elements for ambiguity resolution in interferometry is extended to the interferometric array. Then the interferometric array becomes a completion array or fully augmentable array. The well-known Direct Augmentation Approach (DAA), MUSIC (MUltiple SIgnal Classification) and association method are orderly utilized to resolve the ambiguities and obtain nonambiguous but low-variance DOA estimation. An interferometric spatial smoothing technique for decorrelating coherent signals is also proposed in terms of the array geometry. Simulation results and the results of real data demonstrate the validity and effectiveness of the proposed algorithms. The matrix-completion algorithm has some computational and real-time advantages at the cost of a small increase in hardware.