Resource allocation for secret transmissions on parallel Rayleigh channels

A transmission between two agents, Alice and Bob, over a set of parallel sub-channels is overheard by a third agent Eve, through a second set of parallel sub-channels. All subchannels are flat with random and independent gains and additive white Gaussian noise (AWGN). Alice splits the total amount of available power among the sub-channels, with the purpose of maximizing the communication rate to Bob, under reliability and secrecy constraints. To this end, two schemes are considered. In one case the secret message is encoded with a single wiretap code and then split among the sub-channels. In the latter case the secret message is first split into a number of sub-messages, each separately encoded and transmitted on a different sub-channel. The achievable secrecy rates under a constraint on the secrecy outage probability (SOP) are derived and closed form expressions for Rayleigh fading sub-channels are obtained. In order to limit the complexity of resources optimization (power and rates) we also consider suboptimal solutions based on the selection of active sub-channels over which power is split either equally or according to a waterfilling algorithm with respect to the Alice-Bob channel.

[1]  Hsuan-Jung Su,et al.  On Secrecy Rate of the Generalized Artificial-Noise Assisted Secure Beamforming for Wiretap Channels , 2012, IEEE Journal on Selected Areas in Communications.

[2]  Vinod M. Prabhakaran,et al.  The secrecy capacity of a class of parallel Gaussian compound wiretap channels , 2008, 2008 IEEE International Symposium on Information Theory.

[3]  Shih-Chun Lin,et al.  On Ergodic Secrecy Capacity of Multiple Input Wiretap Channel with Statistical CSIT , 2012, ArXiv.

[4]  Shlomo Shamai,et al.  Secure Communication Over Fading Channels , 2007, IEEE Transactions on Information Theory.

[5]  Hesham El Gamal,et al.  On the Secrecy Capacity of Fading Channels , 2007, ISIT.

[6]  Matthew R. McKay,et al.  Rethinking the Secrecy Outage Formulation: A Secure Transmission Design Perspective , 2011, IEEE Communications Letters.

[7]  Mohamed-Slim Alouini,et al.  Product of shifted exponential variates and outage capacity of multicarrier systems , 2009, 2009 European Wireless Conference.

[8]  Gregory W. Wornell,et al.  Secure Broadcasting Over Fading Channels , 2008, IEEE Transactions on Information Theory.

[9]  H. Vincent Poor,et al.  High SNR secrecy rates with OFDM signaling over fading channels , 2010, 21st Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications.

[10]  H. Vincent Poor,et al.  Physical-Layer Secrecy for OFDM Transmissions Over Fading Channels , 2012, IEEE Transactions on Information Forensics and Security.