Finite-Horizon Online Transmission Scheduling on an Energy Harvesting Communication Link with a Discrete Set of Rates


BACINOĞLU B. T., UYSAL BIYIKOĞLU E.

JOURNAL OF COMMUNICATIONS AND NETWORKS, vol.16, no.3, pp.293-300, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 16 Issue: 3
  • Publication Date: 2014
  • Doi Number: 10.1109/jcn.2014.000049
  • Journal Name: JOURNAL OF COMMUNICATIONS AND NETWORKS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.293-300
  • Middle East Technical University Affiliated: Yes

Abstract

As energy harvesting communication systems emerge, there is a need for transmission schemes that dynamically adapt to the energy harvesting process. In this paper, after exhibiting a finite-horizon online throughput-maximizing scheduling problem formulation and the structure of its optimal solution within a dynamic programming formulation, a low complexity online scheduling policy is proposed. The policy exploits the existence of thresholds for choosing rate and power levels as a function of stored energy, harvest state and time until the end of the horizon. The policy, which is based on computing an expected threshold, performs close to optimal on a wide range of example energy harvest patterns. Moreover, it achieves higher throughput values for a given delay, than throughput-optimal online policies developed based on infinite-horizon formulations in recent literature. The solution is extended to include ergodic time-varying (fading) channels, and a corresponding low complexity policy is proposed and evaluated for this case as well.