Abstract
Facing the challenges of global seamless connectivity and massive user access in 6G mobile communications, this paper investigates movable antenna (MA) enabled non-orthogonal multiple access (NOMA) technology in space-air-ground integrated network (SAGIN). Through dynamic adjustment of antenna spatial positions, MA technology achieves deep synergy between spatial degrees of freedom and power-domain multiplexing, effectively solving the insufficient power differences problem among edge users in traditional NOMA. This article establishes a layered MA-NOMA architecture with differentiated optimization strategies for satellite, aerial, and terrestrial layers, and constructs a cross-layer coordination control framework. Covert communication case studies demonstrate that the MA-NOMA scheme achieves higher system capacity improvements compared to fixed antenna NOMA and MA-OMA schemes respectively, providing important technical support for constructing high-performance 6G SAGIN.