Outage Behavior of Discrete Memoryless Channels Under Channel Estimation Errors

TL;DR

This paper investigates the outage behavior of discrete memoryless channels when channel estimates are imperfect, introducing the estimation-induced outage capacity concept and analyzing its dependence on various channel parameters.

Contribution

It develops a coding theorem and strong converse for estimation-induced outage capacity in channels with estimation errors, providing new theoretical insights.

Findings

Outage capacity depends on SNR, Ricean K-factor, and feedback rate.

Numerical simulations illustrate the impact of channel estimation quality.

Results offer practical insights for designing robust communication systems.

Abstract

Classically, communication systems are designed assuming perfect channel state information at the receiver and/or transmitter. However, in many practical situations, only an estimate of the channel is available that differs from the true channel. We address this channel mismatch scenario by using the notion of estimation-induced outage capacity, for which we provide an associated coding theorem and its strong converse, assuming a discrete memoryless channel. We illustrate our ideas via numerical simulations for transmissions over Ricean fading channels under a quality of service (QoS) constraint using rate-limited feedback channel and maximum likelihood (ML) channel estimation. Our results provide intuitive insights on the impact of the channel estimate and the channel characteristics (SNR, Ricean K-factor, training sequence length, feedback rate, etc.) on the mean outage capacity.