Dynamic magnetic information storage or retrieval – General processing of a digital signal – Pulse crowding correction
Patent
1991-01-22
1993-11-16
Pascal, Robert J.
Dynamic magnetic information storage or retrieval
General processing of a digital signal
Pulse crowding correction
360 40, 360 48, G11B 509
Patent
active
052629040
ABSTRACT:
A method and device for use in measurement and compensation of nonlinear bitshift in nonlinear communication media such as magnetic and optical recording devices. The method and device are based on special bit patterns constructed to eliminate at least one harmonic of the fundamental frequency of the data pattern if all bits are communicated without any nonlinear bitshift. The presence of nonlinear bitshift is manifested by the appearance of the harmonic. By measuring the magnitude of the harmonic, the amount of nonlinear bitshift is determined, and compensation adjustment is then used to offset its effect on the data detection scheme.
REFERENCES:
patent: 3686682 (1972-08-01), Behr et al.
patent: 4009490 (1977-02-01), Fassbender
patent: 4142215 (1979-02-01), Roberts
patent: 4167761 (1979-09-01), Best
patent: 4230799 (1980-05-01), Price
patent: 4251882 (1981-02-01), Pfefferkorn
patent: 4276573 (1981-06-01), Halpern et al.
patent: 4327383 (1982-04-01), Holt
patent: 4612586 (1986-09-01), Sordello et al.
patent: 4764915 (1988-08-01), Efron et al.
patent: 4796109 (1989-01-01), Sordello et al.
patent: 5068754 (1991-11-01), Garde
G. H. Sonu, "Dropout-Error-Rate Calculations for Maximum-Density Study", IEEE Transactions on Magnetics, vol. MAG-21, No. 5, Sep. 1985, pp. 1392-1394.
C. M. Melas et al., "Nonlinear Superposition in Saturation Recording of Disk Media", IEEE Transactions on Magnetics, vol. MAG-23, No. 5, Sep. 1987, pp. 2079-2081.
D. Palmer et al., "Identification of Nonlinear Writhe Effects Using Pseudorandom Sequences", IEEE Transactions, on Magnetics, vol. MAG-23, No. 5, pp. 2377-2379, Sep. 1987.
R. Herman, "Volterra Modeling of Digital Magnetic Saturation Recording Channels" IEEE Transactions on Magnetics, vol. 26, No. 5, Sep. 1990, pp. 2125-2127.
Tang Yaw S.
Tsang Ching H.
Dinh Tan
International Business Machines - Corporation
Kappos David J.
Pascal Robert J.
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