Energy and Spectrum Efficient Systems with Adaptive Modulation and Spectrum Sharing for Cellular Systems

Increasing concern about the energy consumption of cellular networks is driving operators to optimise energy utilisation without sacrificing user experience. In this paper, we consider the capability of spectrum sharing between two or more operators with the objective of achieving energy-efficient operation. Since each operator has a fixed amount of spectrum, they are required to increase the modulation index to achieve a higher data rate for a targeted QoS, which increases the demand on energy. We study the effect of using energy-efficient multilevel quadrature amplitude modulation (MQAM) with the capability of spectrum sharing between operators. Simulations show that using adaptive modulation with spectrum sharing between base stations of different operators can give a more flexible region for the system to operate with a reasonable trade-off.