Energy-Efficiency Optimization for Slow Fluid Antenna Multiple Access Using Mean-Field Game

Fluid antenna multiple access (FAMA) is a new technology that allows mobile devices equipped with a fluid antenna to have a space-division multiple-access (SDMA) capability. In this letter, we investigate the downlink energy efficiency (EE) of the above system. Specifically, the optimal control problem of BS’s transmit power and users’ fluid antenna positions is modeled as a mean-field game (MFG). Results show that the EE using our power control strategy increases as the space of fluid antenna increases and becomes close to the EE of MIMO-SDMA when the space is large.