To reduce the transmission attenuation of millimeter-wave communications, beamforming techniques based on antenna arrays can be adopted to pursue the optimal antenna weight vector, aiming at achieving higher received SNR. One common beamforming technique is the switching beamforming with constant amplitude because of its practicability. The purpose of this study is to design effective beamforming algorithms to reduce the computation complexity as much as possible so that the search time can decrease dramatically.
This paper proposes two search schemes. They are TS (Ternary Search) Scheme and BST (Binary Search with Threshold setting) Scheme.
Theoretical analysis on the design for codebook structures and search algorithms of the two schemes has been made respectively in this paper. This study also completes the MATLAB simulation experiments to prove the feasibility and the veracity of the two schemes. Besides, this paper demonstrates the optimality of the computation complexity and the stability of the two schemes under different premises, and compares their search performances to those of other schemes. Finally, this study draws a conclusion that both TS Scheme and BST Scheme can decrease the search time to some extent. The two schemes, however, have different advantages and disadvantages in different aspects. The computation complexity of BST Scheme is smaller, while TS Scheme overweighs the other in the stability.
Millimeter-wave communications, Beamforming, Ternary search, Binary search, Codebook design