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arXiv · 1703.00143

Codebook Design for Channel Feedback in Lens-Based Millimeter-Wave Massive MIMO Systems

Wenqian Shen·Linglong Dai·Yang Yang·Yue Li·Zhaocheng Wang
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Abstract

The number of radio frequency (RF) chains can be reduced through beam selection in lens-based millimeter-wave (mmWave) massive MIMO systems, where the equivalent channel between RF chains and multiple users is required at the BS to achieve the multi-user multiplexing gain. However, to the best of our knowledge, there is no dedicated codebook for the equivalent channel feedback in such systems. In this paper, we propose the dimension-reduced subspace codebook, which achieves a significant reduction of the feedback overhead and codebook size. Specifically, we firstly utilize the limited scattering property of mmWave channels to generate the high-dimensional vectors in the channel subspace. Then, according to the function of lens and beam selector, we propose the dimension-reduced subspace codebook to quantize the equivalent channel vector.Moreover, the performance analysis of the proposed codebook is also provided.Finally, simulation results show the superior performance of the proposed dimension-reduced subspace codebook compared with conventional codebooks.

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Wenqian Shen, Linglong Dai, Yang Yang, Yue Li, Zhaocheng Wang. 2017-03-01. Codebook Design for Channel Feedback in Lens-Based Millimeter-Wave Massive MIMO Systems. https://arxiv.org/abs/1703.00143

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