Dynamic two-stage beam training for energy-efficient millimeter-wave 5G cellular systems

This paper proposes a polynomial-time protocol for energy-efficient link configuration between 28 GHz millimeter-wave 5G base station antennas and 28 GHz millimeter-wave mobile user antennas. According to the narrow beamwidth of 28 GHz millimeter-wave cellular radio communication links, the link configuration procedure needs to evaluate a lot of link search spaces. Therefore, evaluating an intensively large search space needs a lot of training signal wireless transmission, which dramatically increases the wireless communication power consumption. Therefore, our proposed algorithm reduces the number of training signal transmission, i.e., the number of search space evaluation, using a two-stage dynamic operation for energy-efficient link configuration.