Characterization of Hardware Impairments in Multiple Antenna Systems for DoA Estimation
The authors consider the effects introduced by hardware impairments on the estimation of the Direction of Arrival (DoA) deploying a multiple antenna radio system. They derive a system model from experimental measurements of a state-of-the-art hardware test bed based on RF direct-conversion architecture. The system model includes DC offsets, carrier frequency and phase offsets, and the phase noise. Then, they propose a simple digital compensation algorithm of the impairments for bi-dimensional DoA estimation (azimuth and elevation) with a 3D orthogonal linear array. The robustness of the algorithm in terms of minimum-mean-squared error as a function of the hardware impairments is evaluated and compared with that achieved using the root-MUSIC algorithm.