Fundamental Limits of Energy-Efficient Resource Sharing, Power Control and Discontinuous Transmission

TL;DR

This paper investigates the fundamental limits of energy savings in cellular base stations through power control and discontinuous transmission, demonstrating potential savings of up to 5.5 dB under low load conditions.

Contribution

It provides a comprehensive analysis of power optimization strategies, including DTX and power control, under QoS constraints, and quantifies the maximum achievable energy savings.

Findings

Potential savings of 5.5 dB at low load

Potential savings of 2 dB at high load

Comparison of conventional and optimized schemes

Abstract

The achievable gains via power-optimal scheduling are investigated. Under the QoS constraint of a guaranteed link rate, the overall power consumed by a cellular BS is minimized. Available alternatives for the minimization of transmit power consumption are presented. The transmit power is derived for the two-user downlink situation. The analysis is extended to incorporate a BS power model (which maps transmit power to supply power consumption) and the use of DTX in a BS. Overall potential gains are evaluated by comparison of a conventional SOTA BS with one that employs DTX exclusively, a power control scheme and an optimal combined DTX and power control scheme. Fundamental limits of the achievable savings are found to be at 5.5 dB under low load and 2 dB under high load when comparing the SOTA consumption with optimal allocation under the chosen power model.