Unequal Error Protection: An Information Theoretic Perspective

TL;DR

This paper develops an information theoretic framework for unequal error protection, analyzing the effects of feedback and distinguishing between bit-wise and message-wise UEP on discrete memoryless channels.

Contribution

It introduces a formal information theoretic approach to unequal error protection, highlighting the impact of feedback and differentiating between types of UEP.

Findings

Feedback significantly improves UEP performance.

Distinct behaviors for bit-wise and message-wise UEP are demonstrated.

Results are achieved at rates close to channel capacity.

Abstract

An information theoretic framework for unequal error protection is developed in terms of the exponential error bounds. The fundamental difference between the bit-wise and message-wise unequal error protection (UEP) is demonstrated, for fixed length block codes on DMCs without feedback. Effect of feedback is investigated via variable length block codes. It is shown that, feedback results in a significant improvement in both bit-wise and message-wise UEP (except the single message case for missed detection). The distinction between false-alarm and missed-detection formalizations for message-wise UEP is also considered. All results presented are at rates close to capacity.