Year: 2025
Type: conference-paper
Abstract: We consider the problem of synthesizing a memoryless channel between an unobserved source and a remote terminal. An encoder has access to a partial or noisy version Zn= (Z1, …,Zn) of a remote source sequence Xn= (X1, …,Xn), with (Xi,Zi) independent and identically distributed with joint distribution qX,Z. The encoder communicates through a noiseless link to a decoder which aims to produce an output Yncoordinated with the remote source; that is, the total variation distance between the joint distribution of Xnand Ynand some i.i.d. target distribution $q_{X,Y}^{ \otimes n}$ is required to vanish as n goes to infinity. The two terminals may have access to a source of rate-limited common randomness. We present a single-letter characterization of the optimal compression and common randomness rates. We also show that when the common randomness rate is small, then in most cases, coordinating Znand Ynusing a standard channel synthesis scheme is strictly sub-optimal. In other words, schemes for which the joint distribution of Znand Ynapproaches a product distribution asymptotically are strictly sub-optimal.
Authors: Yassine Hamdi, Deniz Gündüz
Institution: Imperial College London
Language: English
Subfield: Computer Networks and Communications
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4416514060