Multiple Antennas-Based Secure Communications With Channel Inversion Power Control

Abstract

In this letter, a multiple antennas-based truncated channel inversion power control (CIPC) secure transmission scheme with artificial noise (AN) is proposed. Specifically, the transmitter with multiple antennas varies the transmit power as per channel to ensure the received signal power equals a certain constant value <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> , and uses the residual power to transmit AN for interfering the eavesdropper. We first derive the expression for the probability of secure transmission. Relying on this, we then study the optimization problem in terms of the achieved effective secrecy throughput (EST), which quantifies the amount of information that the transmitter can securely send to the receiver, subject to the constraints that the probability of secure transmission is no less than a predetermined value. The numerical results show that increasing the transmission power will not continuously decrease the probability of secure transmission. Furthermore, we find that there exists an optimal <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> to maximize the EST performance, and the optimal value of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> increases with the number of antennas.