Secrecy Capacity Region of Fading Broadcast Channels

TL;DR

This paper characterizes the secrecy capacity region of fading broadcast channels with confidential messages, deriving optimal power allocations and applying results to Gaussian and fading scenarios.

Contribution

It establishes the secrecy capacity region for the fading broadcast channel with confidential messages, including the Gaussian case, and derives optimal power allocations.

Findings

Secrecy capacity region for parallel Gaussian BCC derived.

Optimal source power allocations identified.

Ergodic secrecy capacity region for fading BCC established.

Abstract

The fading broadcast channel with confidential messages (BCC) is investigated, where a source node has common information for two receivers (receivers 1 and 2), and has confidential information intended only for receiver 1. The confidential information needs to be kept as secret as possible from receiver 2. The channel state information (CSI) is assumed to be known at both the transmitter and the receivers. The secrecy capacity region is first established for the parallel Gaussian BCC, and the optimal source power allocations that achieve the boundary of the secrecy capacity region are derived. In particular, the secrecy capacity region is established for the Gaussian case of the Csiszar-Korner BCC model. The secrecy capacity results are then applied to give the ergodic secrecy capacity region for the fading BCC.