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Title: Subspace-Aware Index Codes

Abstract

In this paper, we generalize the well-known index coding problem to exploit the structure in the source-data to improve system throughput. In many applications (e.g., multimedia), the data to be transmitted may lie (or can be well approximated) in a low-dimensional subspace. We exploit this low-dimensional structure of the data using an algebraic framework to solve the index coding problem (referred to as subspace-aware index coding) as opposed to the traditional index coding problem which is subspace-unaware. Also, we propose an efficient algorithm based on the alternating minimization approach to obtain near optimal index codes for both subspace-aware and -unaware cases. In conclusion, our simulations indicate that under certain conditions, a significant throughput gain (about 90%) can be achieved by subspace-aware index codes over conventional subspace-unaware index codes.

Authors:
ORCiD logo [1];  [1];  [1]
  1. Syracuse Univ., NY (United States). Department of EECS
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1393342
Report Number(s):
LLNL-JRNL-718227
Journal ID: ISSN 2162-2337
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
IEEE Wireless Communications Letters
Additional Journal Information:
Journal Volume: 6; Journal Issue: 3; Journal ID: ISSN 2162-2337
Publisher:
IEEE
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING; Indexes; Encoding; Optimization; Throughput; Decoding; Servers; Receivers

Citation Formats

Kailkhura, Bhavya, Theagarajan, Lakshmi Narasimhan, and Varshney, Pramod K. Subspace-Aware Index Codes. United States: N. p., 2017. Web. doi:10.1109/LWC.2017.2693362.
Kailkhura, Bhavya, Theagarajan, Lakshmi Narasimhan, & Varshney, Pramod K. Subspace-Aware Index Codes. United States. doi:10.1109/LWC.2017.2693362.
Kailkhura, Bhavya, Theagarajan, Lakshmi Narasimhan, and Varshney, Pramod K. Wed . "Subspace-Aware Index Codes". United States. doi:10.1109/LWC.2017.2693362. https://www.osti.gov/servlets/purl/1393342.
@article{osti_1393342,
title = {Subspace-Aware Index Codes},
author = {Kailkhura, Bhavya and Theagarajan, Lakshmi Narasimhan and Varshney, Pramod K.},
abstractNote = {In this paper, we generalize the well-known index coding problem to exploit the structure in the source-data to improve system throughput. In many applications (e.g., multimedia), the data to be transmitted may lie (or can be well approximated) in a low-dimensional subspace. We exploit this low-dimensional structure of the data using an algebraic framework to solve the index coding problem (referred to as subspace-aware index coding) as opposed to the traditional index coding problem which is subspace-unaware. Also, we propose an efficient algorithm based on the alternating minimization approach to obtain near optimal index codes for both subspace-aware and -unaware cases. In conclusion, our simulations indicate that under certain conditions, a significant throughput gain (about 90%) can be achieved by subspace-aware index codes over conventional subspace-unaware index codes.},
doi = {10.1109/LWC.2017.2693362},
journal = {IEEE Wireless Communications Letters},
number = 3,
volume = 6,
place = {United States},
year = {Wed Apr 12 00:00:00 EDT 2017},
month = {Wed Apr 12 00:00:00 EDT 2017}
}

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