MIMO Gaussian Broadcast Channels with Common, Private and Confidential Messages
Abstract
The two-user multiple-input multiple-output (MIMO) Gaussian broadcast channel (BC) with common, private and confidential messages is considered. The transmitter sends a common message to both users, a confidential message to User 1 and a private (non-confidential) message to User 2. The secrecy-capacity region is characterized by showing that certain inner and outer bounds coincide and that the boundary points are achieved by Gaussian inputs, which enables the development of a tight converse. The proof relies on factorization of upper concave envelopes and a variant of dirty-paper coding (DPC). It is shown that the entire region is exhausted by using DPC to cancel out the signal of the non-confidential message at Receiver 1, thus making DPC against the signal of the confidential message unnecessary. A numerical example illustrates the secrecy-capacity results.
Keywords
Cite
@article{arxiv.1608.06057,
title = {MIMO Gaussian Broadcast Channels with Common, Private and Confidential Messages},
author = {Ziv Goldfeld and Haim H. Permuter},
journal= {arXiv preprint arXiv:1608.06057},
year = {2019}
}