3 research outputs found
An Achievable Rate Region for Three-Pair Interference Channels with Noise
An achievable rate region for certain noisy three-user-pair interference
channels is proposed. The channel class under consideration generalizes the
three-pair deterministic interference channel (3-DIC) in the same way as the
Telatar-Tse noisy two-pair interference channel generalizes the El Gamal-Costa
injective channel. Specifically, arbitrary noise is introduced that acts on the
combined interference signal before it affects the desired signal. This class
of channels includes the Gaussian case.
The rate region includes the best-known inner bound on the 3-DIC capacity
region, dominates treating interference as noise, and subsumes the
Han-Kobayashi region for the two-pair case.Comment: 9 pages, 3 figures; abbreviated version to be presented at IEEE
International Symposium on Information Theory (ISIT 2012
On Communication through a Gaussian Channel with an MMSE Disturbance Constraint
This paper considers a Gaussian channel with one transmitter and two
receivers. The goal is to maximize the communication rate at the
intended/primary receiver subject to a disturbance constraint at the
unintended/secondary receiver. The disturbance is measured in terms of minimum
mean square error (MMSE) of the interference that the transmission to the
primary receiver inflicts on the secondary receiver.
The paper presents a new upper bound for the problem of maximizing the mutual
information subject to an MMSE constraint. The new bound holds for vector
inputs of any length and recovers a previously known limiting (when the length
of vector input tends to infinity) expression from the work of Bustin
The key technical novelty is a new upper bound on the MMSE.
This bound allows one to bound the MMSE for all signal-to-noise ratio (SNR)
values a certain SNR at which the MMSE is known (which
corresponds to the disturbance constraint). This bound complements the
`single-crossing point property' of the MMSE that upper bounds the MMSE for all
SNR values a certain value at which the MMSE value is known.
The MMSE upper bound provides a refined characterization of the
phase-transition phenomenon which manifests, in the limit as the length of the
vector input goes to infinity, as a discontinuity of the MMSE for the problem
at hand.
For vector inputs of size , a matching lower bound, to within an
additive gap of order (where
is the disturbance constraint), is shown by means of the mixed
inputs technique recently introduced by Dytso Comment: Submitted to IEEE Transactions on Information Theor