Secrecy Rate Maximization With Uncoordinated Cooperative Jamming by Single-Antenna Helpers Under Secrecy Outage Probability Constraint

The issue of physical layer security for single-input-multiple-output (SIMO) wiretap channel with uncoordinated cooperative jamming (UCJ) is addressed in this letter, and we focus on power allocation in secrecy rate maximization (SRM) problem. Differing from the existing works, a practical UCJ scheme is proposed by using multiple single-antenna helpers where each helper transmits a jamming signal independently to confound the eavesdropper. Assuming that statistical channel state information (CSI) concerning the eavesdropper is available, a modified DC (difference of convex function) programming method is provided to solve the SRM problem under secrecy outage probability constraint and an achievable solution of power allocation is obtained. Numerical results show that the proposed scheme has satisfactory secrecy performance especially when the number of helpers is large.