A Differential Feedback Scheme Exploiting the Temporal and Spectral Correlation

TL;DR

This paper introduces a differential feedback scheme that leverages both temporal and spectral correlations in MIMO channels to significantly reduce feedback load, improving system efficiency in limited feedback scenarios.

Contribution

It proposes a novel differential feedback method that fully exploits temporal and spectral correlations, and analyzes the minimal feedback rate for doubly selective fading channels.

Findings

The scheme effectively reduces feedback bits in MIMO systems.

Analysis of minimal differential feedback rate is provided.

Simulation results confirm the scheme's efficiency.

Abstract

Channel state information (CSI) provided by limited feedback channel can be utilized to increase the system throughput. However, in multiple input multiple output (MIMO) systems, the signaling overhead realizing this CSI feedback can be quite large, while the capacity of the uplink feedback channel is typically limited. Hence, it is crucial to reduce the amount of feedback bits. Prior work on limited feedback compression commonly adopted the block fading channel model where only temporal or spectral correlation in wireless channel is considered. In this paper, we propose a differential feedback scheme with full use of the temporal and spectral correlations to reduce the feedback load. Then, the minimal differential feedback rate over MIMO doubly selective fading channel is investigated. Finally, the analysis is verified by simulations.