SWIPT in MISO Multicasting Systems

This letter considers simultaneous wireless information and power transfer (SWIPT) in multiple-input single-output (MISO) multicasting systems where each receiver is equipped with a power splitting device and can receive both information and energy from the base station (BS) continuously at the same time. We investigate the joint multicast transmit beamforming and receive power splitting problem for minimizing the transmit power of the BS subject to signal-to-noise ratio (SNR) and energy harvesting constraints at each receiver. Both scenarios of perfect and imperfect channel state information (CSI) at the BS are studied. Due to non convexity of the problems, we use semidefinite relaxation (SDR) technique to solve the problems. Interestingly, we show that the SDR is in fact tight in certain scenarios.