# Energy Efficient Beamforming for Massive MIMO Public Channel

## TL;DR

This paper proposes a novel beamforming design for massive MIMO public channels that minimizes transmit power while ensuring QoS, using an iterative optimization approach and hybrid implementation to improve efficiency.

## Contribution

It introduces a new beamforming method based on ideal beampattern derivation and multiconvex optimization, with practical hybrid implementation for energy efficiency.

## Key findings

- Reduced transmit power compared to existing schemes
- Improved power amplifier efficiency without changing beampattern
- Effective hybrid beamforming implementation verified by simulations

## Abstract

For massive MIMO public channel with any sector size in either microwave or millimeter wave (mmwave) band, this paper studies the beamforming design to minimize the transmit power while guaranteeing the quality of service (QoS) for randomly deployed users. First the ideal beampattern is derived via Parseval Identity, based on which a beamforming design problem is formulated to minimize the gap with the idea beampattern. The problem is transformable to a multiconvex one and an iterative optimization algorithm is used to obtain the full-digital beamformer. In addition, with the help of same beampattern theorem, the power amplifier (PA) efficiency of the beamformer is improved with unchanged beampattern. Finally, the practical hybrid implementation is obtained that achieves the full-digital beamformer solution. Simulations verify the advantages of the proposed scheme over existing ones.