US 5,963,525 A · Process for reading information

Abstract

A process for reading binary information written on a carrier. The carrier has at least one track and the binary information is written onto the carrier at a frequency Fbit. The process includes the step of reading binary information at the sampling frequency F.sub.e to form a succession of successive read samples SAM(k) of the same track. SAM(k) is the read sample of order k, each read sample having a phase .phi.(k) lying between 0 and 2.pi.. The method further includes a step of interpolating to make it possible to calculate an interpolated sample I(k) with phase equal to .pi. which corresponds to read sample SAM(k) on the basis of the read sample and on the i+j read samples which bracket the original read sample SAM(k) such that: I(k)=a.sub.k-i SAM(k-i)+ . . . +a.sub.k SAM(k)+ . . . +a.sub.k+j SAM(k+j) The coefficients have values which depend on the chosen law of interpolation and a step of validation makes it possible to generate an information item intended to validate or invalidate the interpolated sample. The process is especially useful for the reading of binary information written on a large number of tracks.

Claims20

Dependent claims

A process for reading binary information written on a carrier in at least one track, the binary information having been written onto the carrier at a frequency Fbit, said process comprising:

reading said binary information at a sampling frequency F.sub.e so as to form a succession of successive read samples from the at least one track, each read sample being a read sample of order k, k being a positive integer, each of the read samples of order k having a phase .phi.(k) lying between 0 and 2.pi.;
calculating an interpolated sample with a phase equal .pi. to using a particular read sample and a number of successive ones of the succession of read samples which precede and follow the particular read sample, with each of the number of successive ones of read samples and the particular read sample being weighted by a related coefficient having a respective value dependent on a particular law of interpolation chosen;
and
providing an information item indicating whether or not the calculated interpolated sample is a validated interpolated sample or an invalidated interpolated sample.

1 more element

A system for reading binary information written on a magnetic carrier in at least one track, the binary information having been written onto the carrier at a frequency Fbit, comprising:

a magnetic head reading said binary information at a sampling frequency F.sub.e so as to form a succession of k successive read samples from the at least one track, k being a positive integer;
an interpolation portion calculating an interpolated sample for each read sample using a particular read sample and a number of successive ones of the succession of read samples which precede and follow the particular read sample, with each of the number of successive ones of read samples and the particular read sample being weighted by related coefficients, each of the related coefficients having a respective value dependent on a particular law of interpolation chosen;
and
a validation generator providing an information item indicating whether or not the calculated interpolated sample is a validated interpolated sample or an invalidated interpolated sample.

1 more element

A system for reading binary information written on a magnetic carrier in at least one track, the binary information having been written onto the carrier at a frequency Fbit, comprising:

a magneto-optic reading head transforming into luminous information the binary information read simultaneously on the at least one track at a sampling frequency F.sub.e ;
a charge-transfer photosensitive device gathering the luminance information and transforming the luminance information into a succession of successive voltage samples, the photosensitive device further comprising at least one output supplying the voltage samples,
a delay portion connected to the at least one output and rearranging the voltage samples supplied by the at least one output so as to obtain a succession of k voltage samples from the at least one track, k being a positive integer;
an interpolation portion calculating an interpolated sample for each voltage sample using a particular voltage sample and a number of successive ones of the succession of voltage samples which precede and follow the particular voltage sample, with each of the number of successive ones of voltage samples and the particular voltage sample being weighted by related coefficients, each one of the coefficients having a respective value dependent on a particular law of interpolation chosen;
and
a validation generator providing an information item indicating whether or not the calculated interpolated sample is a validated interpolated sample or an invalidated interpolated sample.

3 more elements

Dependencies are inferred from the claim text.

Process for reading information

Life of this patent

Process for reading information

Life of this patent

Abstract

Claims20