Physical layer security in UWB networks

The omnipresent wireless medium provides high mobility, yet the very nature of open medium introduces vulnerability. Earlier designs of security mechanisms concentrated more on the upper layers, but physical layer techniques have recently gained popularity. Security is taken care of by maximizing the information rate of the signal sent from the source to the receiver, with an assumption that the eavesdropper´s channel is worse than the main channel. User cooperation scheme is utilized to jam the eavesdropper´s signal. We have considered a channel model including the path loss exponent and Rayleigh fading, with an aim to maximize secrecy rate under transmit power constraint. Simulations have been done for the secrecy rate in different environments and also how it varies with the position of the receiver and eavesdropper.