Non-orthogonal Multiple Access Enabled Power Allocation for Cooperative Jamming in Wireless Networks

Abstract

In this work, we investigate the non-orthogonal multiple access (NOMA) enabled power allocation for cooperative jamming under a two-user downlink scenario. In particular, we consider that there exists a malicious eavesdropper overhearing the data transmission of the mobile user (MU) with a stronger channel power gain. Meanwhile, exploiting the simultaneous transmission in NOMA, we consider that the other MU with a weak channel power gain provides cooperative jamming to the eavesdropper for enhancing the secure throughput of the stronger MU. In particular, we formulate a power allocation problem to maximize the secure throughput of the strong MU while satisfying the throughput requirement of the weak MU. Despite the non-convexity of the formulated problem, we provide an efficient algorithm to compute the optimal solution (i.e., the power allocations for the two users). Numerical results are provided to validate the effectiveness of our proposed algorithm and the performance of our optimal power allocation scheme.