Abstract: Cooperative transmission in a decode-and-forward (DF) two-hop network where multiple cooperative nodes coexist with a potential eavesdropper can be secured with enhanced relay selection strategy and interference can be reduced by the use of an adaptive filter at the receiver. Under the practical assumption that only the channel distribution information (CDI) of the eavesdropper is known, also we propose an Arti?cial jamming and beamforming, where a “best” cooperative node is chosen among a collection of N possible cooperative nodes based on the transmission rate and SNR to forward the con?dential signal and the others send jamming signals to confuse the eavesdroppers. Since the optimization problems are non-convex, we use a sequential parametric convex approximation (SPCA) algorithm to locate the Karush Kuhn-Tucker (KKT) solutions; we generalize the analysis with multiple eavesdroppers, and find the asymptotic analytical results of the achievable ESR. Simulation results con?rm our analytical results. We also obtain the simulation of capacity and BER with respect to SNR to show the effectiveness of the system.

Keywords: Adaptive filters, beam forming, decode and forward, ergodic secrecy rate, extreme order statistics, outdated CSIs, Sequential parametric convex approximation.