Analysis of One-Way and Two-Way Relay Networks Affected by Hardware Impairments

Abstract

Physical transceivers have impaired hardware which creates distortions that degrade the performance of the communication system. The majority of contributions in the technical area of relaying ignore hardware impairments and assume that the hardware is ideal.Such approximations are true for low rate systems but can provide very misleading results for a high rate system. Wireless relaying system with relay selection helps to improve the coverage and boost throughput in cellular network. Also, training based systems that obtain channel state information for performing their operation are extensively used in the modern LTE Advanced technology. However, the process of obtaining channel state information (CSI)by the channel estimation to is often accompanied by errors leading to degradation in the system performance. Also the hardware impairments in the transceivers of the relaying systems cause severe degradation in performance. Although, literature investigating their impact on relaying systems is limited. In this work,the impact of hardware impairments and channel estimation errors on one-way relay(OWR) and two-way relay(TWR) system for amplify and forward protocols have been investigated.This thesis also investigate the effects of hardware impairments on multi -relay system for both partial relay selection(PRS) and opportunistic relay selection (ORS). The expressions for end-to-end signal-to-noise ratio (SNR) and a exact closed-form expression for the analysis of outage probabilities (OP) are derived by taking a Rayleigh block fading channel.Finally, these results are validated through Monte Carlo simulations.