Joint source-channel coding with time-varying channel and side-information
File(s)
Accepted version
Author(s)
Estella-Aguerri, I
Gunduz, D
Type
Journal Article
Abstract
Transmission of a Gaussian source over a timevarying Gaussian channel is studied in the presence of timevarying correlated side information at the receiver. A block fading model is considered for both the channel and the side information, whose states are assumed to be known only at the receiver. The optimality of separate source and channel coding in terms of average end-to-end distortion is shown when the channel is static while the side information state follows a discrete or a continuous and quasiconcave distribution. When both the channel and side information states are time-varying, separate source and channel coding is suboptimal in general. A partially informed encoder lower bound is studied by providing the channel state information to the encoder. Several achievable transmission schemes are proposed based on uncoded transmission, separate source and channel coding, joint decoding as well as hybrid digital-analog transmission. Uncoded transmission is shown to be optimal for a class of continuous and quasiconcave side information state distributions, while the channel gain may have an arbitrary distribution. To the best of our knowledge, this is the first example in which the uncoded transmission achieves the optimal performance thanks to the time-varying nature of the states, while it is suboptimal in the static version of the same problem. Then, the optimal distortion exponent, that quantifies the exponential decay rate of the expected distortion in the high SNR regime, is characterized for Nakagami distributed channel and side information states, and it is shown to be achieved by hybrid digital-analog and joint decoding schemes in certain cases, illustrating the suboptimality of pure digital or analog transmission in general.
Date Issued
2016-02-01
Date Acceptance
2015-07-08
Citation
IEEE Transactions on Information Theory, 2016, 62 (2), pp.736-753
ISSN
0018-9448
Publisher
Institute of Electrical and Electronics Engineers
Start Page
736
End Page
753
Journal / Book Title
IEEE Transactions on Information Theory
Volume
62
Issue
2
Copyright Statement
© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Identifier
https://ieeexplore.ieee.org/document/7348712
Subjects
Science & Technology
Technology
Computer Science, Information Systems
Engineering, Electrical & Electronic
Computer Science
Engineering
Distortion exponent
joint source-channel coding
fading channel and side information
side information diversity
uncoded transmission
hybrid digital-analog transmission
joint decoding
DISTORTION SNR EXPONENT
GAUSSIAN SOURCE
EXPECTED DISTORTION
BROADCAST
TRANSMISSION
DIVERSITY
CODES
Networking & Telecommunications
0801 Artificial Intelligence and Image Processing
0906 Electrical and Electronic Engineering
1005 Communications Technologies
Publication Status
Published
Date Publish Online
2015-12-07