Performance of Diversity Combining Schemes and Power Allocation for Amplify-and-Forward Relaying Over Frequency Selective Fading Channel

摘要

Cooperative communication describes strategies to transfer the data from the source to the destination by employing relay nodes between the source and the destination. In order to reduce the complexity and power consumption, one or more relays are selected to send the data from the source to the destination. In this paper, the performance of different schemes of combining the output of the relays at the destination is studied over frequency selective fading channel. The relaying protocol is Amplify-and-Forward (AF) relaying protocol and the noise is assumed to be additive white Gaussian noise. Zero forcing equalization is used to reduce the effect of inter-symbol interference. Power allocation among the nodes is considered in order to distribute the limited resources in a best way. Simulation results are provided to evaluate the performance of different combining schemes. Results show that increasing the number of combined relay branches gives the best performance in terms of bit error rate but requires more power, while choosing the best relay requires less power but gives worse performance in terms of bit error rate.