Interleaved Training Codebook Design for Millimeter-wave Communication System

In order to meet the high data-rate requirements in next-generation wireless systems, millimeter-wave (mmwave) band has drawn increasing attention. However, the channel training and transmission design become more challenging. Interleaved training-based transmission scheme can achieve the same outage performance as the traditional full-training scheme but with lower average training overhead. This paper studies improved designs of interleaved training codebook for mmwave hybrid massive antenna downlink systems. Via exploiting the spatial features of the mmwave massive downlink channel, the original discrete Fourier transform (DFT) codebook is adjusted via beamsteering design, flat topped design and codebook rearrangement. Simulations show that these specific codebook designs can further reduce the average training overhead of the interleaved scheme compared with existing DFT codebook.