This paper addresses the problem of scalability for a cell-free massive MIMO (CF-mMIMO) system that performs integrated sensing and communications (ISAC). Specifically, the case where a large number of access points (APs) are deployed to perform simultaneous communication with mobile users and monitoring of the surrounding environment in the same time-frequency slot is considered, and a target-centric approach on top of the user-centric architecture used for communication services is introduced. In the paper, other practical aspects such as the fronthaul load and scanning protocol are also considered. The proposed scalable ISAC-enabled CF-mMIMO network has lower levels of system complexity, permits managing the scenario in which multiple targets are to be tracked/sensed by the APs, and achieves performance levels superior or, in some cases, close to those of the non-scalable solutions.

翻译：本文研究了执行集成感知与通信（ISAC）的无蜂窝大规模MIMO（CF-mMIMO）系统的可扩展性问题。具体而言，考虑了在相同时频资源块中部署大量接入点（AP）以同时执行与移动用户的通信及对周围环境监测的场景，并在用于通信服务的以用户为中心的网络架构基础上，引入了一种以目标为中心的方法。本文还考虑了前传负载与扫描协议等其他实际因素。所提出的可扩展支持ISAC的CF-mMIMO网络具有较低的系统复杂度，能够处理AP需跟踪/感知多个目标的场景，并且其性能表现优于或（在某些情况下）接近不可扩展的解决方案。