Beamforming Codebook Design and Performance Evaluation for Millimeter-Wave WPAN

摘要

The paper proposes a codebook design to realize beamforming mechanism in a wide band millimeter-wave 60-GHz wireless personal area network (60GHz WPAN) in a realistic millimeter-wave environment. The codebooks are designed symmetrically in order to mitigate the possible beam shift due the large difference of wave length at different band of a wide band communication system. In order to provide a high data rate and high performance to minimize power consumption in 60GHz systems, the codebooks are generated with only 4 phase shifts (0 90 180 270 degree) without amplitude adjustment. The codebooks are designed for different number of antenna elements, supporting a multitude of antenna configurations. The paper provides codebook design mechanism, some of example codebooks and some analysis on antenna gain loss due to phase error of antenna array. Simulation results shows that: (1) To keep the gain loss at the intersection points of two beams lower than 1dB, the number of patterns inside the codebook shall be 2 times more than the number of antenna elements used for pattern generation; (2) With the help of proposed codebook design mechanism, the designed codebooks are robust to phase errors: the gain loss is lower than 1dB with only 10% outflow probability when standard deviation of phase error is 0.5 [28.6 degree] for each of phase shifters. The proposed codebooks are a feasible design, they are the key basis of beamforming protocol in 60GHz WPAN (IEEE 802.15.3c).