Power Efficient Transmission of Time Multiplexed Unicast and Broadcast Cellular Communications

Abstract

In this paper, a new power adjustment technique for the time multiplexing of LTEunicast and broadcast is proposed to reduce the wasted downlink powerin unicast slots. In addition to compensating the propagation losses (distance-loss, shadowing and fast fading), the proposed technique adapts the signal-tointerference-plus-noise ratio (SINR) to be fit in the required range. The power adjustmentalgorithm uses a predefined SINR threshold (SINR_th) specific for each service and data rate. When the measured SINR of the user equipment SINR_UE is above (lower) than the SINR_th, the decrease (increase) of power is ordered adaptively depending on the difference between the two values. The proposed techniqueis evaluated by simulation where numerical results quantitatively outline the benefits on system performance, achieved in terms of average downlink transmitted power, average saved energy and outage probability of SINR_UEversus userspeed.