Performance Analysis and Codebook Design for mmWave Beamforming System with Beam Squint

TL;DR

This paper analyzes the impact of beam squint on wideband mmWave beamforming systems and proposes a new codebook design that mitigates performance degradation caused by beam squint effects.

Contribution

It introduces an optimized codebook design that accounts for beam squint, improving wideband beamforming performance in mmWave systems.

Findings

The proposed codebook spreads beam coverage to counteract beam squint effects.

Simulation shows significant performance improvement with the new codebook.

The analysis derives the average spectrum efficiency considering beam squint.

Abstract

Beamforming technology is widely used in millimeter wave systems to combat path losses, and beamformers are usually selected from a predefined codebook. Unfortunately, the traditional codebook design neglects the beam squint effect, and this will cause severe performance degradation when the bandwidth is large. In this letter, we consider that a codebook with fixed size is adopted in the wideband beamforming system. First, we analyze how beam squint affects system performance when all beams have the same width. The expression of average spectrum efficiency is derived based on the ideal beam pattern. Next, we formulate the optimization problem to design the optimal codebook. Simulation results demonstrate that the proposed codebook deals with beam squint by spreading the beam coverage and significantly mitigates the performance degradation.