A Power-Balanced Alamouti Scheme with Security Protection

Due to advancements in modern mobile communication technology, massive numbers of devices are now connected to the internet, but the associated information also has to be well protected. Many studies have proposed physical layer security (PLS) approaches utilizing artificial noise (AN), which is a simple approach to protecting information from an illegal receiver. However, this approach requires additional power allocation for AN. This paper proposes an efficient power balancing method for the Alamouti scheme, which provides efficient security capability as well as enhancement of power efficiency. The simulation results investigated in this paper reveal that the proposed scheme requires about 5 dB smaller power to achieve the same performance as that of the conventional AN-aided scheme, and eventually, about 2 dB less power than the conventional scheme without PLS.