By Topic

Joint estimation of data and timing in the presence of inter-symbol interference

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
B. A. Wilson ; Almaden Res. Center, IBM Corp., San Jose, CA, USA ; R. New ; J. Campello ; B. Marcus

A channel with inter-symbol interference and random perturbations to timing is approximated using a finite-state Markov model. The inter-symbol interference is approximated by a finite-impulse response and the timing perturbations are approximated by a first-order random walk. A Viterbi algorithm is then applied to find the maximum-likelihood sequence of states on this model. The resulting state sequence defines the data sequence and timing trajectory which jointly maximize a likelihood function on the observed signal. This approach provides a means of detecting data with rapidly fluctuating timing perturbations at low signal-to-noise ratio. This is particularly relevant to data storage applications where mechanical fluctuations are translated into timing perturbations. Codes can be incorporated into the detector. The coding gain improves the reliability of both data detection and timing recovery. Codes which can be represented using a reasonably small state machine, such as trellis codes and high rate block parity codes, can be incorporated directly into the finite state model. For iterative decoders a BCJR algorithm can also be applied to this state machine to yield a posteriori probabilities on the data bits.

Published in:

IEEE Transactions on Magnetics  (Volume:39 ,  Issue: 5 )