LAUSR

Beam tracking can be utilized to compensate for beam misalignment and avoid performance degradation in millimeter wave (mmWave) systems. In order to reduce the training overhead, attitude information obtained from motion sensors has been proposed to assist beam tracking. In this letter, we extend attitude information aided beam tracking to the practical systems with codebook-based beamforming. Moreover, estimation errors of attitude information are inevitable in practical systems, and lead to a trade-off in codebook design: wider beams suffer more from insufficient power; narrower beams are more sensitive to the error. Therefore, it is necessary to design a codebook with appropriate beamwidth. We first derive the optimal beamwidth that maximizes the average transmission rate based on the sectored beam model. Further, we consider the codebook with overlapping beams, which can prevent misalignment. Then, both the optimal beamwidth and overlap ratio are derived. Finally, simulation results validate the performance of the proposed methods.