On Bandwidth Efficiency Analysis for LS-MIMO With Hardware Impairments

Large scale multiple-input-multiple output (LS-MIMO) systems are one of the most promising candidates for 5th generation wireless communication networks. Many researchers have claimed that LS-MIMO systems increase energy efficiency (EE) and bandwidth efficiency (BE) exponentially because of large number of antennas. Significant increase in transmission directivity also increases sum rate and data throughput but implementation of LS-MIMO is complex in terms of hardware. As the number of antenna elements increase, it becomes necessary that the manufacturing material of antenna must be very cheap and size of antenna element should be very compact. Large number of antenna elements and other hardware components induce different impairments in the system due to amplifier distortion, quantization noise, and phase noise. Since these impairments come as a gift with large scale antenna regime and they effect EE and BE of the system, it is necessary to investigate them for practical scenarios. In this paper, we consider a LS-MIMO single cell scenario with the inclusion of hardware impairments. We derive new expressions for MMSE estimator and achievable rates including effects of hardware impairments. We analyze hardware impairments on the basis of derived expressions. We perform simulations using derived sophisticated impairments model with realistic measurements.