A review of UAV positioning in LAIN: toward a 5G-core “space−air−ground” integrated and cooperative architecture

• Standalone positioning technologies are inadequate in complex low-altitude settings; multi-source fusion and UAV swarm cooperative positioning are identified as pivotal future trends. • A novel “space−air−ground” integrated and cooperative positioning architecture centered on GNSS and 5G is proposed for low-altitude intelligent networks. • The three-layer (ground, aerial, space) architecture reuses existing infrastructure to reduce deployment costs and deeply integrates communication and navigation capabilities. • The proposed framework enhances positioning robustness and provides cost-effective, ubiquitous, and highly reliable positioning services, while highlighting promising research directions for LAIN.