Synesthesia of Machines (SoM)-Enhanced ISAC Precoding for Vehicular Networks with Double Dynamics
Zonghui Yang, Shijian Gao, Xiang Cheng, Liuqing Yang
TL;DR
This work tackles ISAC precoding in vehicular networks under doubly dynamic conditions (time-varying channels and fast-moving targets). It introduces a synesthesia-of-machine (SoM) concept and a PSAC-based DRL framework to fuse multi-modal observations (CSI and position) for robust, real-time precoding via a hybrid action space. Complementing this, an optimization-based baseline with full state information and a frame-structured ISAC processing pipeline illustrate performance and complexity tradeoffs. Simulation results show DRL‑aided precoding yields notable SE and sensing improvements, with close-to-ideal performance under realistic dynamics and reduced computational burden. The approach offers a practical pathway toward timely, high‑fidelity ISAC in dynamic vehicular environments.
Abstract
Integrated sensing and communication (ISAC) technology is vital for vehicular networks, yet the time-varying communication channels and rapid movement of targets present significant challenges for real-time precoding design. Traditional optimization-based methods are computationally complex and depend on perfect prior information, which is often unavailable in double-dynamic scenarios. In this paper, we propose a synesthesia of machine (SoM)-enhanced precoding paradigm that leverages modalities such as positioning and channel information to adapt to these dynamics. Utilizing a deep reinforcement learning (DRL) framework, our approach pushes ISAC performance boundaries. We also introduce a parameter-shared actor-critic architecture to accelerate training in complex state and action spaces. Extensive experiments validate the superiority of our method over existing approaches.
