Analysis of the energy efficiency of a Virtual MIMO system with a large antenna array

By means of wireless cooperation, Virtual Multiple-Input Multiple-Output (V-MIMO) systems provide significant enhancements in terms of spectral efficiency and performance. A large V-MIMO system that implements bit-interleaved coded-modulation (BICM) transmission and decode-and-forward (DF) cooperation is considered in this paper. The energy consumption is an important metric so we study the energy efficiency (EE) and the effective throughput (E_T) of a V-MIMO with large antenna array. A comparison of the EE when the available resource blocks are constrained is presented. The EE simulation results show that the optimal throughput is obtained when there is no restriction on the use of resource blocks, since there is no overhead power consumption incurred by the relays. In a practical scenario where a number of users terminals (UTs) are sharing the resources, a cooperative system offers a higher EE than increasing the modulation order.