Dynamic magnetic information storage or retrieval – General processing of a digital signal – Head amplifier circuit
Patent
1994-08-17
1995-06-06
Psitos, Aristotelis
Dynamic magnetic information storage or retrieval
General processing of a digital signal
Head amplifier circuit
360 51, 360 65, G11B 509, G11B 2710, G11B 5035
Patent
active
054227607
ABSTRACT:
A class IV partial response, maximum likelihood data channel for a disk drive includes an encoder connected to a data sequencer for converting user data blocks into a predetermined 8/9ths code such as a (0,4,4,) code. A precoder conveys the 8/9ths code into class IV code. An analog write driver supplies the class IV code to a data transducer head during data write-to-disk operations. A read channel connected to the head amplifies and conditions analog signals during data read operations. A quantizer produces samples of the analog signals in accordance with a quantization clock generated by a clock generator. An adaptive FIR filter means is conditions the data samples in accordance with selectable, adaptive filter coefficients. A Viterbi detector puts out the class IV code from the filtered and quantized samples. A postcoder conveys the detected class IV code into detected 8/9ths code. A decoder converts the detected 8/9ths code into user data and supplies user data to the sequencer. The programmable FIR filter is provided with servo coefficients during reading of the servo sectors, and an asynchronous servo detector detects head position information from the quantized and filtered samples without phase locking of the quantization clock generator to the quantized servo samples. The asynchronous servo detector is also used to aid detection of sync field preamble information before the FIR filter is fully adapted. Multi-mode gain and timing loops are also a part of the present invention.
REFERENCES:
patent: 4504872 (1985-03-01), Peterson
patent: 4644564 (1987-02-01), Dolivo et al.
patent: 4750058 (1988-06-01), Hirt et al.
patent: 4847871 (1989-07-01), Matsushita et al.
patent: 4890299 (1989-12-01), Dolivo et al.
patent: 5060088 (1991-10-01), Dolivo et al.
patent: 5121263 (1992-06-01), Kerwin et al.
patent: 5132988 (1992-07-01), Fisher et al.
patent: 5150379 (1992-09-01), Baugh et al.
patent: 5220466 (1993-06-01), Coker et al.
patent: 5255131 (1993-10-01), Coker et al.
Wood, Peterson, "Viterbi Detection of Class IV Parrtial Response on a Magnetic Recording Channel", IEEE Trans on Comm. vol. Com-34, No. 5, May 1986, pp. 454-461.
Schmerbeck, Richetta, Smith, "A 27 MHz Mixed Analog/Digital Magnetic Recording Channel DSP using Partial Response Signalling with Maximum Likelihood Detection" Proc. 1991 IEEE Int'l Solid State Circuits Conf., pp. 136-137, 304, and pp. 96, 97, 256 Slide Supplement.
Wood, Ahigrim, Hollarnasek, Swenson, "An Experimental Eight-Inch Disc Drive with 100 MBytes per Surface", IEEE Trans on Magnetics, vol. MAG-20, No. 5, Sep. 1984 pp. 698-702.
Kobayashi, Tang, "Application of Partial--Response Channel Coding to Magnetic Recording Systems", IBM Journal of Research & Develop., Jul. 1970, pp. 368-375.
Kobayashi, "Application of Probabilistic Decoding to Digital Magnetic Recording Systems", IBM Journal Research & Develop., Jan. 1971, pp. 64-74.
Dolivo, "Signal Processing of High-Density Digital Magnetic Recording", Proc. 1989 IEEE VLSI & Computer Peripherals, Hamburg, W. Germany, May, 1989, pp. 1-91 to 1-96.
Coker, Galbraith, Kewin, Rae, Ziperovich, "Implementation of PRML in a Rigid Disk Drive", IEEE Trans. on Magnetics, vol 27, No. 6, Nov. 1991.
Cideciyan, Dolivo, Hermann, Hirt, Schott, "A PRML System for Digital Magnetic Recording", IEEE Journal on Selected Areas of Comm., vol. 10, No. 1, Jan. 1992, pp. 38-56.
Abbott William L.
Johnson Kenneth E.
Nguyen Hung C.
Harrison David B.
Kim Won Tae C.
Psitos Aristotelis
Quantum Corp.
LandOfFree
Disk drive method using zoned data recording and PRML sampling d does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Disk drive method using zoned data recording and PRML sampling d, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Disk drive method using zoned data recording and PRML sampling d will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-991915