MIMO Precoding Using Rotating Codebooks

TL;DR

This paper introduces a rotating codebook method for MIMO precoding that enhances performance without increasing feedback bandwidth by expanding the effective codebook size through multiple rotating codebooks.

Contribution

It proposes a novel rotating codebook technique that improves MIMO precoding performance while maintaining minimal feedback overhead.

Findings

Performance gain over conventional precoding

Effective codebook size expansion without additional feedback

Simulation results confirm improvements

Abstract

Next generation wireless communications rely on multiple input multiple output (MIMO) techniques to achieve high data rates. Feedback of channel information can be used in MIMO precoding to fully activate the strongest channel modes and improve MIMO performance. Unfortunately, the bandwidth of the control channel via which the feedback is conveyed is severely limited. An important issue is how to improve the MIMO precoding performance with minimal feedback. In this letter, we present a method that uses a rotating codebook technique to effectively improve the precoding performance without the need of increasing feedback overhead. The basic idea of the rotating codebook precoding is to expend the effective precoding codebook size via rotating multiple codebooks so that the number of feedback bits remains unchanged. Simulation results are presented to show the performance gain of the proposed rotating codebook precoding over the conventional precoding.