Performance analysis of multi-antennas combining and selection schemes for wireless-powered communication

We propose and analyze spatial diversity combining and selection schemes in a wireless-powered communication network with multi-antennas at energy access point (EAP) and data access point (DAP). The EAP adopts either maximal-ratio transmitting or transmit antenna selection to wirelessly transfer power, and the DAP employs either maximal-ratio combining or receive antenna selection to combine the received information. It generates four schemes for the wireless-powered communication network. We derive new closed-form expressions for the statistical characterizations of the received signal to noise ratio (SNR). Based on these expressions, the outage probability and the average throughput are further derived. The diversity order of the proposed schemes is given through the asymptotic outage probability analysis at high SNR regime. Nakagami-m fading with non-identical fading parameters is assumed for both power transfer channel and information transmission channel. Numerical results are given to validate all the analytical results. The impact of EAP transmit power, the number of EAP/DAP antennas, and the energy harvesting time on the performance of the proposed schemes is also investigated.