Energy Efficient Beamforming Optimization for Integrated Sensing and Communication

TL;DR

This paper proposes an iterative algorithm for optimizing energy-efficient beamforming in integrated sensing and communication systems, balancing multiuser communication performance with radar sensing requirements.

Contribution

It introduces a novel reformulation and solution approach using SCA and SDR techniques, with proven tightness of the relaxation for the first time.

Findings

The proposed algorithm effectively maximizes energy efficiency.

The SDR relaxation is proven to be tight.

Numerical results confirm the algorithm's effectiveness.

Abstract

This paper investigates the optimization of beamforming design in a system with integrated sensing and communication (ISAC), where the base station (BS) sends signals for simultaneous multiuser communication and radar sensing. We aim at maximizing the energy efficiency (EE) of the multiuser communication while guaranteeing the sensing requirement in terms of individual radar beampattern gains. The problem is a complicated nonconvex fractional program which is challenging to be solved. By appropriately reformulating the problem and then applying the techniques of successive convex approximation (SCA) and semidefinite relaxation (SDR), we propose an iterative algorithm to address this problem. In theory, we prove that the introduced relaxation of the SDR is rigorously tight. Numerical results validate the effectiveness of the proposed algorithm.