The Effect of the Broadband Jammer on a Distributed Beamforming Performance in a Relay Network

In this paper, the effect of the broadband jammer is considered in two relay communications networks for various positions of the jammer. The first and second network has one and r relays, respectively. In both networks, each relay has one antenna and use Amplify and Forward (AF) protocol to transmit messages. Each of the source and the destination uses one antenna to send and receive messages, respectively. In the first network, the source transmits its signal in two relay-link and direct-link path stoward the destination. In the second network, each relay transmits its received signal after adjusting its power toward the destination. Simulation results show for the first network that when a jammer is close to the source, the jamming effect increases, and in the second network, if the jammer is near to relays, quality of service decrease.