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arXiv · 2503.14054

Dynamic Joint Communications and Sensing Precoding Design: A Lyapunov Approach

Abolfazl Zakeri·Nhan Thanh Nguyen·Ahmed Alkhateeb·Markku Juntti
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Abstract

This letter proposes a dynamic joint communications and sensing (JCAS) framework to adaptively design dedicated sensing and communications precoders. We first formulate a stochastic control problem to maximize the long-term average signal-to-noise ratio for sensing, subject to a minimum average communications signal-to-interference-plus-noise ratio requirement and a power budget. Using Lyapunov optimization, specifically the drift-plus-penalty method, we cast the problem into a sequence of per-slot non-convex problems. To solve these problems, we develop a successive convex approximation method. Additionally, we derive a closed-form solution to the per-slot problems based on the notion of zero-forcing. Numerical evaluations demonstrate the efficacy of the proposed methods and highlight their superiority compared to a baseline method based on conventional design.

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Abolfazl Zakeri, Nhan Thanh Nguyen, Ahmed Alkhateeb, Markku Juntti. 2025-03-18. Dynamic Joint Communications and Sensing Precoding Design: A Lyapunov Approach. https://arxiv.org/abs/2503.14054

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