  Beam training based on hierarchical codebook for millimeter wave (mmWave)
massive MIMO is investigated. Unlike the existing work using the same
hierarchical codebook to estimate different multi-path components (MPCs),
dynamic hierarchical codebooks which are updated according to the estimated
MPCs are adopted. Firstly, a generalized hierarchical codebook design method is
proposed. Then based on this method, a beam training method which dynamically
updates the hierarchical codebook by removing the contribution of the estimated
MPCs from the codebook is proposed. Simulation results verify the effectiveness
of our method and show that the proposed method outperforms the existing ones
in terms of the success detection rate of beam training.
