Three-state search algorithm for codebook-based beamforming

Beamforming is one of the most important techniques in MIMO wireless communication. It enhances the signal strength and also depresses the undesired signals. In this paper, we propose a beam searching method for the codebook-based beamforming technique, which is recently applied in the millimeter wave wireless network. As the element number of the antenna array increases, the time needed to search the best beam-pair for data transmissions becomes a critical problem in wireless communication performance. This method compares the ratio of the SINR received by two adjacent beams to obtain the information of the central beam. The simulation results with codebook in IEEE 802.15.3c standard prove that the proposed method can significantly reduce the time necessary to set up the beam pair in term of number of training sequences compared with conventional searching techniques.