以欠采样速率实现盲谱感知及二维DOA估计

提出了两种以欠采样率实现盲谱感知与二维波达方向(DOA)估计的算法。这两种算法利用了MWC的周期信号所对应的傅里叶级数系数矩阵来确定未知信号频谱所在的子频带位置，然后利用二维阵列的信号模型估计得到包含二维DOA的空间相位。通过空间相位信息与子频带位置信息能重构出子带谱信息，以此能得到频率的高精度估计，最后通过空间相位分别估计得到信号的方位角与俯仰角。仿真验证了所提欠采样接收机与相应算法的有效性，以及在低信噪比环境下依然有较好的鲁棒性。

Achieving Blind Spectrum Sensing and Two-Dimensional DOA Estimation with Sub-Nyquist Sampling Rate

This paper proposes two algorithms for achieving blind spectrum sensing and two-dimensional direction of arrival (DOA) estimation in an arbitrary two-dimensional array receiver with sub-Nyquist sampling. The two proposed algorithms utilize the Fourier series coefficient matrix of the periodic signal of modulated wideband converter (MWC) to determine the sub-band positions of signal spectra, and then take advantage of the signal model derived from the two-dimensional array to estimate the spatial phases which contains two-dimensional DOA. Based on the estimated information, the sub-band spectra are reconstructed so that carrier frequencies can be estimated with high precision. Finally, the azimuth- and elevation-angles of signals are estimated through spatial phases, respectively. Simulation results verify the effectiveness and high robustness of the proposed sub-Nyquist sampling receiver and the algorithms under environment with a low signal-to-noise ratio.