Performance analysis of multi-antenna multi-hop relay networks using antenna selection with delayed channel state information at the transmitter

Present wireless technologies demand high quality broadband services even at cell edges. Multi-hop relay (MHR) network is one of the suitable solutions for the above demands. The standards like IEEE 802.16j and Long Term Evolution (LTE) are using relay architecture which mainly focuses on capacity and coverage improvement. In recent days, multi antenna MHR networks are becoming more popular. However obtaining accurate channel state information (CSI) has become a crucial issue in MHR network performance. In this paper, we analyze the effect of delayed CSI at the transmitter (CSIT) in a system with N transmit antennas and one receive antenna, which uses antenna selection (AS). Assuming perfect CSI at the receiver (CSIR), only two out of the N transmit antennas is selected by the receiver and the indices for the same are fed back to the transmitter over a noiseless link with some finite delay. Thus this paper studied the reduced multiple input single output (MISO) systems for MHR networks which perform well even with delayed CSIT. The simulation results also validate the same.