Space Time Block Coding aided physical layer security in Gaussian MIMO channels

This paper analyze the problem of secret communication between two nodes over a wireless channel, in the presence of a passive eavesdropper. The effect of fading is also considered. It is assumed that the transmitter and receiver both have 2 antennas each while the eavesdropper consists of a single antenna. The article investigates this scenario using Alamouti Space Time Block Coding (STBC) and artificial noise. This approach significantly improves the physical layer security of the system. Moreover, the secrecy capacity of this system is also computed.