Rate-distortion perspectives in goal-oriented semantic communications

Stavrou, Photios
WOLIT 2023, International Workshop on Learning and Information Theory, 3-5 July 2023, Shenzhen & Hong Kong, China

In this talk, the goal is to stress the usefulness of rate distortion theory and its variants in identifying fundamental limitations in goal-oriented semantic communications. In the first part of the talk, we discuss a variant of a robust description lossy source coding problem. Particularly, for the proposed setup, we demonstrate the cardinal role of multiple fidelity constraints in designing selective decoders which in turn dictate the outcome of the reconstructed message depending on the task. We also discuss a less restrictive class of fidelity constraints, called f-separable distortions, which allow for a much richer class of distortion penalties (e.g., exponential, polynomial, logarithmic) between the transmitted signal and the received signal. An algorithm for computing the resulting rate-distortion characterizations via the alternating minimization approach is also discussed. In the second part of this talk, we consider a variant of rate distortion function, called rate-distortion-perception function, and explain its utility in goal-oriented compression. Here we primarily discuss optimization viewpoints and algorithms that allow the computation of this function for finite alphabet sources, when the distortion criterion is separable and the perception constraint belongs to the family of f-divergences. An interesting result herein is the derivation of a robust approximate iterative method with provable convergence guarantees, that is shown to converge to the globally optimal solution. In the third part of this talk and if time permits, we will also talk about a lower bound on the optimal performance theoretically attainable by causal and zero-delay codes, called non-anticipative rate distortion function, and demonstrate its utility in constructing achievable bounds in a low-delay variable-rate lossy source coding setup that necessitates causal reconstruction of the source message, one of the key features of goal-oriented semantic communications from an information-theoretic standpoint. The utility of this bound, is also demonstrated in identifying the synthesis and the performance analysis of a quantized closed-loop controlled network.


Type:
Talk
City:
Shenzhen
Date:
2023-07-05
Department:
Systèmes de Communication
Eurecom Ref:
7322
Copyright:
© 2023 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
See also:

PERMALINK : https://www.eurecom.fr/publication/7322