Performance of Product Codes on Channels with Memory

A channel with memory has the characteristics of introducing correlated error bursts in transmitted data symbols. The inter-symbol interference and dropout effects in magnetic tape channels contribute to correlated error sequences in the read-back signal. A product-code-based error correcting scheme is used in conventional tape drive systems to combat these effects and to guarantee very high data fidelity. The read-back signal from the tape is decoded using a hard-decision distance-bounded decoder of the product code. In this paper, we present an analytical method to evaluate the performance of product codes on tape channels described as hidden Markov models. The performance measures of interest are symbol and codeword error rates of product codes. In addition to presenting the performance curves of the product code used in present day tape drive systems, we propose alternate error correcting schemes that can be considered for implementation in future generations.

By: S. Sankaranarayanan; Evangelos S. Eleftheriou

Published in: Proc. IEEE Int'l Symp. on Information Theory "ISIT 2005," Adelaide, Australia, September 2005 (IEEE, 2005).Adelaide, Australia in 2005

LIMITED DISTRIBUTION NOTICE:

This Research Report is available. This report has been submitted for publication outside of IBM and will probably be copyrighted if accepted for publication. It has been issued as a Research Report for early dissemination of its contents. In view of the transfer of copyright to the outside publisher, its distribution outside of IBM prior to publication should be limited to peer communications and specific requests. After outside publication, requests should be filled only by reprints or legally obtained copies of the article (e.g., payment of royalties). I have read and understand this notice and am a member of the scientific community outside or inside of IBM seeking a single copy only.

rz3579.pdf

Questions about this service can be mailed to reports@us.ibm.com .