One-Bit-Aided Modulo Sampling for DOA Estimation

Due to the limited dynamic range of the conventional ADC, the information loss is inevitable for direction-of-arrival (DOA) estimation in the near-far case. Recently, the modulo ADC is proposed to overcome this fundamental bottleneck. This paper introduces a sampling scheme that integrates the modulo ADC with a one-bit ADC and employs the one-bitaided blind integer-forcing (1bit-aided-BIF) algorithm for DOA estimation. First, the one-bit samples provide an estimate of the normalized covariance matrix of the unquantized measurements via the arcsin law. Then, the estimate of the normalized covariance matrix is used to implement the BIF decoder to unwrap the modulo samples. Given unfolded samples, the subspace methods can be used to perform the DOA estimation. Numerical experiments show that the proposed sampling architecture and algorithm achieve a bit-depth gain of 2 to 3 compared to the conventional ADC.