Security gap assessment for the fast fading wiretap channel

Using the error rate as a metric is useful for assessing the performance of actual transmission schemes from the physical layer security viewpoint. The security gap concept has been used over the additive white Gaussian noise channel as a practical measure for combined reliability and security. In this paper, the definition of security gap is extended to a wire-tap channel with fast fading. Our aim is to show that by introducing scrambling and error correction coding can significantly reduce the required quality difference between the channel of the authorized user and that of the unauthorized one.