Loading…

ARQ with Subcarrier Assignment for OFDM Systems

We consider an automatic-repeat-request (ARQ) scheme in OFDM systems. When a transmission fails, the transmitter repeats the data symbols in the retransmission, but on different subcarriers. The receiver then performs maximal- ratio combining (MRC) on the data symbols in the original and ARQ transmi...

Full description

Saved in:
Bibliographic Details
Main Authors: Chin Keong Ho, Hongming Yang, Pandharipande, A., Bergmans, J.W.M.
Format: Conference Proceeding
Language:English
Subjects:
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We consider an automatic-repeat-request (ARQ) scheme in OFDM systems. When a transmission fails, the transmitter repeats the data symbols in the retransmission, but on different subcarriers. The receiver then performs maximal- ratio combining (MRC) on the data symbols in the original and ARQ transmissions, before symbol detection is carried out. Our goal is to determine subcarrier assignment of the data symbols in the retransmission, such that utility functions which determine system-level performances are maximized. We show that when the utility function is Schur concave, the optimum solution is to assign the ARQ subcarrier with the largest SNR to the original subcarrier with the smallest SNR. Further, we propose heuristic solutions when some imposed constraints are relaxed.
ISSN:1058-6393
2576-2303
DOI:10.1109/ACSSC.2007.4487527