Research on Single-Snapshot DOA Estimation with Large-Scale Antenna Arrays

In the single-snapshot large-scale uniform antenna arrays, traditional subspace-based Direction of Arrival (DOA) estimation methods are ineffective due to the reliance on multi-snapshot data and high computational complexity. This paper proposes a novel DOA estimation method for single-snapshot conditions. Initially, the Inverse Discrete Fourier Transform (IDFT) is employed to acquire the initial DOA estimation value, upon which a new mathematical model is constructed. Subsequently, the initial estimation value is denoised by the unrolled gradient descent network, thereby enhancing the estimation accuracy. Ultimately, the offset angle is estimated via Taylor expansion, leading to the precise DOA angle. The simulations have shown that our proposed technique achieves satisfactory DOA estimation accuracy in scenarios with only a single snapshot. This approach significantly mitigates the shortcomings typically encountered with conventional techniques in such settings. Moreover, it presents an innovative strategy for effective DOA estimation with extensive antenna arrays under single-snapshot constraints.