PRACH Power Control Mechanism for Improving Random-Access Energy Efficiency in Long Term Evolution

Abstract

The Random Access (RA)procedure is one of the most frequently used and energy consuming operations in LTE User Equipment (UE)devices. However, little attention has been given to its energy-efficient operation in the literature. In this paper, we propose two Physical Random Access Channel (PRACH)power control mechanisms for improving the energy efficiency of the overall RA procedure. Our proposals increase the preamble transmit power based on special characteristics of the UE energy consumption behavior. By doing this, the number of transmitted preamble per successful RA procedure decreases, thus obtaining important energy savings. Our simulation results show that our proposals can reduce up to 41 percent the energy consumption of the RA procedure when compared to the standardized PRACH power control mechanism with power ramping.