Power Allocation under Given Secret Key Generation Rate for Secure Wireless OFDM Systems.

Generating a secret key from the physical layer is one of the most challenging topics in cryptography. Secret key generation rate (SKGR) and secrecy rate (SR) are two important concepts for any secure communication scheme. In this paper, we first propose a new power allocation strategy to minimize the power consumption under a given SKGR constraint for orthogonal frequency division (OFDM) based communication systems. Due to the non-convex nature of the SKGR expression, we convert the optimization problem into a convex problem. In the continuation of this paper, we investigate the effects of the proposed power allocation strategy on the SR performance. Simulation results demonstrate that using the obtained optimum power vector, which was calculated in the key generation phase, we achieve a better level of SR in the data communication phase. The simulation results also verify that the average SR performance obtained by the proposed method is superior to the geometric programing (GP)-based method. [ABSTRACT FROM AUTHOR]