Performance analysis of energy harvesting communications using multiple time slots

Abstract

Energy harvesting provides a promising alternative to batteries and mains used by current wireless devices. However, the power supply in energy harvesting communications becomes dynamic due to the random channels. In this work, the authors study two energy harvesting communications protocols, `harvest-store-use' and `harvest-use'. A linear harvester is used to collect energy over multiple time slots for the two protocols. The effective throughput for `harvest-store-use' and the average bit error rate for `harvest-use' are derived. Numerical results show that there exists an optimum number of time slots for the `harvest-store-use' protocol to balance the transmission probability and the delay and that the effective throughput approaches an upper limit when the number of time slots increases. Also, for the `harvest-use' protocol, one should use a small number of time slots to balance the bit error rate performance and the battery consumption.