Imperfect jamming cancellation on NOMA networks with randomly located eavesdroppers

This paper addresses the secrecy performance of the downlink of a non-orthogonal multiple access network in the presence of multiple randomly located eavesdroppers. The network consists of a base station and a near receiver that are located inside a protected zone, free of eavesdroppers, while a far user is located outside. Herein, it is considered that the source transmits a superposed jamming signal to enhance the secrecy performance. In this sense, imperfections on the removal of the jamming signal by the legitimate receivers are also investigated. Integral-form exact and closed-form approximate expressions for the secrecy outage probability are derived by employing stochastic geometry tools. The expressions are corroborated via Monte Carlo simulations.