Secrecy Outage Probability of Multiple-Input–Multiple-Output Secure Internet of Things Communication Systems

The multiple-input-multiple-output (MIMO) scheme enhances the capacity and reliability of secure Internet of Things (IoT) communication systems. In this article, an MIMO secure IoT communication system which includes a multiantenna transmitter, a multiantenna legitimate receiver, and a multiantenna eavesdropper is investigated. Considering that the transmitter and receiver are deterministic whereas the eavesdropper is either deterministic or randomly distributed, we theoretically derive the secrecy outage probabilities (SOPs) in independent and identically distributed (i.i.d.) as well as full-correlated Rayleigh fading channels. The i.i.d. or full-correlated Wishart matrices are introduced to express the mutual information rates from the transmitter to the legitimate receiver and eavesdropper. By analyzing the joint probability density functions of unordered eigenvalues of Wishart matrices, we obtain the moment generating functions (MGFs) of mutual information rates. Employing inverse Laplace transforms of the MGFs, the SOPs are obtained. Simulation results show the close agreement between the simulated and analytical results.