Practical Cooperative Relaying with Imperfect Channel Knowledge

Abstract

Cooperative Communications is a new and emerging concept in the world of wireless communications, which aims to overcome multipath fading effects by employing diversity. In a cooperative network, multiple antennae transmit the same information to receiver nodes known as relays. These relays then forward the information to destination nodes. The team attempted to demonstrate that employing relay selection techniques can significantly improve the quality of service in cooperative networks. The project aimed to implement a cooperative relaying network using software-defined radios (SDR) test-bed. The test-bed was implemented using GNU Radio and universal software radio peripheral (USRP) platform and the performance of the proposed scheme was empirically evaluated. The primary focus of the project was to outline the advantages of employing instantaneous relay selection in cooperative networks and improvements in bit error rate (BER) performances. In this respect, several experiments were conducted in the information processing and transmission (IPT) lab. These included setting up cooperative networks with a varying number of relays, hop distances and transmit powers. The BER for such networks were then determined at the destination node. It was seen that the BER performance improved after applying relay selection techniques.