Energy Harvesting Transmitters that Heat Up: Throughput Maximization under Temperature Constraints

TL;DR

This paper investigates optimal data transmission strategies for energy harvesting sensors that must limit temperature rise, deriving solutions that maximize throughput while respecting thermal constraints.

Contribution

It introduces a novel model linking temperature dynamics with energy harvesting, providing structural solutions for optimal power policies under thermal constraints.

Findings

Optimal power policy is piecewise monotone decreasing with jumps at energy arrivals.

In single energy arrival scenarios, power decreases monotonically and temperature increases monotonically.

Solutions are generalized for multiple energy arrivals, maintaining temperature constraints.

Abstract

Motivated by damage due to heating in sensor operation, we consider the throughput optimal offline data scheduling problem in an energy harvesting transmitter such that the resulting temperature increase remains below a critical level. We model the temperature dynamics of the transmitter as a linear system and determine the optimal transmit power policy under such temperature constraints as well as energy harvesting constraints over an AWGN channel. We first derive the structural properties of the solution for the general case with multiple energy arrivals. We show that the optimal power policy is piecewise monotone decreasing with possible jumps at the energy harvesting instants. We derive analytical expressions for the optimal solution in the single energy arrival case. We show that, in the single energy arrival case, the optimal power is monotone decreasing, the resulting temperature is monotone increasing, and both remain constant after the temperature hits the critical level. We then generalize the solution for the multiple energy arrival case.