Cooperative sensing and communication beamforming design for low-altitude economy

This paper proposes a cooperative integrated sensing and communication (ISAC) framework to support the low-altitude economy with high-accuracy sensing and high-rate communication. In the framework, ground base stations (BSs) use coordinated beamforming to cooperatively serve heterogeneous unmanned aerial vehicles (UAVs) performing either ISAC or sensing-only tasks. To maximize the weighted sum rate subject to sensing signal-to-interference-plus-noise ratio (SINR) constraints, we jointly optimize the BS transmit beamforming, UAV receive filtering, and UAV trajectories. An efficient alternating optimization algorithm, incorporating semidefinite relaxation (SDR) and successive convex approximation (SCA), is developed to solve the challenging non-convex problem. Simulation results demonstrate that the proposed joint cooperative design achieves superior communication throughput while ensuring sensing robustness, and underscore the necessity of adapting UAV trajectories to varying sensing requirements, BS transmit power and altitudes.