Optimal Universal Power Management Policies for Channels with Slow-Varying Harvested Energy

In this paper, we study power management (PM) policies for an Energy Harvesting Additive White Gaussian Noise (EH-AWGN) channel. We assume that the arrival energy sequence varies independently across data packets (blocks) according to a known arbitrary distribution, but it remains constant during each data packet. The harvested energy sequence is known causally (online) at the transmitter. The transmitter is supplied with a battery, and the battery is rechargeable with unlimited storage capacity. The transmitter is able to adapt the allocated energy and the corresponding transmission rate of each block according to a PM policy. Three novel online PM policies are established. The policies are universal, in the sense of the distribution of the harvested energy, and simple, in the sense of complexity, and asymptotically optimal, in the sense of maximum achievable (long term) average data rates named as the channel throughput.