Energy efficiency of partial-cooperative multi-cell system based on interference zero-forcing

Recently the escalation of energy consumption in wireless communication system leads an increasing interest to consider the energy efficiency (EE) of the system. One of the possible approaches for reducing the energy consumption is base station (BS) cooperation, which is referred as coordinated multipoint (CoMP) transmission. In this paper, an energy efficient optimization problem is considered for a partial-cooperative multi-cell MIMO system. The interference zero-forcing (I-ZF) technique is proposed to solve the optimization problem. The I-ZF technique is similar to the the zero-forcing beamforming method in a single cell system. It can fully cancel the interference, which contains the inter-cell interference and intra-cell interference. Based on the I-ZF, the optimal EE and optimal power allocation are gained. We compare the optimal EE with the conventional capacity maximizing schemes. The simulation results demonstrate that the optimal EE based on I-ZF has a better EE performance than the conventional schemes. Moreover, the EE is affected by the circuit power consumption, backhaul link dissipation, path loss factor and distance between BS and the user.