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Collection InformationProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection.
AbstractToday I will describe the application of the Autocorrelation function to the Magnetic Recording Channel. I will explain what is an autocorrelated function, how does it behave and where may it be applied in the Magnetic Recording channel. There will be a brief description of Kodak San Diego’s Autocorrelator and how we apply this technology. If I have done my job well at the end of this presentation you will have enough knowledge about autocorrelation to access your own application. Before I start, let me give a brief overview on the application of an Autocorrelator. The Autocorrelator can be used to collect information on signals in a magnetic recording system and display this information graphically as a statistical plot. Autocorrelation, in the time domain, is the counter part to a spectrum analyzer in the frequency domain (Fourier Pair). The information about the signal of interest must be stored for post analysis. This information called a database must then be processed by a computer. The computer passes the database through the autocorrelation algorithm and produces a second database. This second database represents a plot of the autocorrelated function. The next step is to plot the database on a video screen. This plot can be examined for periodicities, randomness, and relational influences on a captured signal. In our application, this signal is an error flag or a dropout flag. We want a statistical picture of the magnitude of errors and their relative frequency. The information gained from Autocorrelation can aid in solutions for: Error Correction Codes Media Evaluation/Qualifications Media Process Defect Identification Mechanical Eccentricities Modulation Code Performances System’s Figure of Merit To use a cliche, “one picture is worth a thousand words,” is exactly the point of the Autocorrelator’s graphical display. It yields information useful to those disciplines which often find difficulty in describing an event in understandable terms.
SponsorsInternational Foundation for Telemetering