Secure Miso Beamforming Optimization With Randomly Distributed Eavesdroppers And Interferers

In this paper, for the conventional MISO wiretap channel, we take into account the locations' random nature regarding those eavesdroppers and the ambient interferers in the wireless networks. For the convenience of mathematical analysis, these location distributions are modeled as Poisson point processes (PPPs). We assume that the transmitter Alice has no channel state information (CSI) about the other nodes except that it knows the statistical CSI of links about the legitimate user Bob and those eavesdroppers. In order to improve the security of Bob, we further set up a protected zone (PZ) to prevent excessive eavesdroppers from overhearing confidential signals. We investigate the probabilities of connection outage and secrecy outage to derive the closed form expression of secrecy transmission rate. Afterwards, we formulate an secrecy rate maximization problem and solve it to determine the optimized beamforming vector. The numerical results reveal the superiority of the proposed beamforming optimization over the relevant eigen beamforming design in [1].