ECO-ISAC · Towards Cost- and Energy-Efficient Cell-Free ISAC In Sub-6 GHz and mmWave HetNets

Future sixth-generation (6G) networks will demand the seamless integration of communication, sensing, and computation to support emerging applications such as autonomous mobility, digital twins, healthcare for aging populations, and smart cities. Integrated sensing and communication (ISAC) has been identified by the ITU-R in its IMT-2030 vision as a key enabler of 6G. However, most existing ISAC studies are limited to either sub-6 GHz or mmWave-only networks and offer limited insight into cost- and energy-efficient large-scale deployment of ISAC systems. This project, ECO-ISAC, aims to develop a cost- and energy-efficient framework for cell-free massive MIMO (CF-mMIMO)-based ISAC, explicitly incorporating practical constraints while enabling multi-user communication and multi-target localization. The proposed approach will unify analytical modeling across sub-6 GHz and mmWave heterogeneous networks, providing insights into practical system designs such as resource allocation, frequency selection, and power control. In parallel, dedicated ISAC signal designs will be developed to guarantee both communication reliability and sensing accuracy. Novel algorithms will be developed for multi-target localization under realistic CF constraints and benchmarked against state-of-the-art methods. A distinctive feature of ECO-ISAC is its focus on physical implementation. A CF-ISAC prototype will be developed on a software-defined radio (SDR) platform, enabling cost-effective and flexible hardware realization. The expected outcomes include: (i) a unified analytical framework for CF-ISAC in sub-6 GHz and mmWave HetNets; (ii) efficient algorithms for multi-target localization and multi-user communication under practical constraints; and (iii) an SDR-based prototype demonstrating feasibility and scalability. Collectively, these results will provide both theoretical foundations and experimental validation for the cost- and energy-efficient deployment of CF-ISAC in future 6G networks.