Secrecy capacity of a class of broadcast channels with an eavesdropper
EURASIP Journal on Wireless Communications and Networking - Special issue on wireless physical layer security
Cooperation with an untrusted relay: a secrecy perspective
IEEE Transactions on Information Theory
Two-hop secure communication using an untrusted relay
EURASIP Journal on Wireless Communications and Networking - Special issue on wireless physical layer security
Hi-index | 754.90 |
We investigate the effects of user cooperation on the secrecy of broadcast channels by considering a cooperative relay broadcast channel. We show that user cooperation can increase the achievable secrecy region. We propose an achievable scheme that combines Marton's coding scheme for broadcast channels and Cover and El Gamal's compress-and-forward scheme for relay channels. We derive outer bounds for the rate-equivocation region using auxiliary random variables for single-letterization. Finally, we consider a Gaussian channel and show that both users can have positive secrecy rates, which is not possible for scalar Gaussian broadcast channels without cooperation.