Sensing-Assisted UAV-BS Recovery for Invisible Evacuee Demand Along Predefined Evacuation Corridors

Post-disaster emergency communication networks often suffer from coverage degradation
and limited network observability, which makes it difficult to maintain reliable connectivity
for evacuees. Existing UAV-assisted communication methods usually rely on network-side
visible metrics for deployment decisions. As a result, they may overlook evacuees whose
communication demands are hidden in coverage blind zones or observation blind zones
along predefined evacuation corridors. To address this problem, this paper proposes a
sensing-assisted UAV-BS recovery method for invisible evacuee demand. The method
constructs an invisible-demand map by combining sensed evacuee states, ground coverage
conditions, network observation states, and evacuation urgency. It further introduces
an evacuation-flow demand map to describe continuous communication demand along
evacuation corridors. These two maps are combined to guide temporary UAV-BS access
recovery. The simulation results show that the proposed method achieves the best overall
balance among invisible-demand recovery, evacuation-path coverage, and edge evacuee
rate. Compared with the blind-zone-only baseline, it improves DCR (demand coverage
ratio) from 0.365 to 0.373, DW-EPC (demand-weighted evacuation-path coverage) from
0.286 to 0.316, and the fifth-percentile evacuee rate from 1.559 to 1.672 bps/Hz. The
proposed method also shows more stable performance under sensing-output uncertainty
and constrained UAV response radius.