Detecting Unauthorized Drones with Cell-Free Integrated Sensing and Communication
Xinyue Li, Zinat Behdad, Ozan Alp Topal, Ozlem Tugfe Demir, Cicek Cavdar
TL;DR
This work addresses detecting unauthorized drones in a cell-free massive MIMO ISAC network while satisfying downlink communication requirements. It jointly optimizes sensing blocklength and transmit power to maximize sensing coverage and minimize Age of Sensing, introducing a CCP-based adaptive weight-selection method to balance precision and timeliness. A MAPR detector is employed for multi-static aerial target detection, and AoS together with sensing coverage serve as core performance metrics. Numerical results show the adaptive weighting approach can reduce AoS by up to 45% while achieving over 98% sensing coverage, demonstrating efficient resource utilization and real-time aerial threat detection capability.
Abstract
Integrated sensing and communication (ISAC) boosts network efficiency by using existing resources for diverse sensing applications. In this work, we propose a cell-free massive MIMO (multiple-input multiple-output)-ISAC framework to detect unauthorized drones while simultaneously ensuring communication requirements. We develop a detector to identify passive aerial targets by analyzing signals from distributed access points (APs). In addition to the precision of the sensing, timeliness of the sensing information is also crucial due to the risk of drones leaving the area before the sensing procedure is finished. We introduce the age of sensing (AoS) and sensing coverage as our sensing performance metrics and propose a joint sensing blocklength and power optimization algorithm to minimize AoS and maximize sensing coverage while meeting communication requirements. Moreover, we propose an adaptive weight selection algorithm based on concave-convex procedure to balance the inherent trade-off between AoS and sensing coverage. Our numerical results show that increasing the communication requirements would significantly reduce both the sensing coverage and the timeliness of the sensing. Furthermore, the proposed adaptive weight selection algorithm can provide high sensing coverage and reduce the AoS by 45% compared to the fixed weights, demonstrating efficient utilization of both power and sensing blocklength.
