WO2009060525A1 - 磁気ヘッド評価方法、装置及び評価回路 - Google Patents

磁気ヘッド評価方法、装置及び評価回路 Download PDF

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Publication number
WO2009060525A1
WO2009060525A1 PCT/JP2007/071714 JP2007071714W WO2009060525A1 WO 2009060525 A1 WO2009060525 A1 WO 2009060525A1 JP 2007071714 W JP2007071714 W JP 2007071714W WO 2009060525 A1 WO2009060525 A1 WO 2009060525A1
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WO
WIPO (PCT)
Prior art keywords
magnetic head
code
evaluating
recording
recorded
Prior art date
Application number
PCT/JP2007/071714
Other languages
English (en)
French (fr)
Inventor
Hiroshi Uno
Keiji Shimatani
Original Assignee
Fujitsu Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Limited filed Critical Fujitsu Limited
Priority to JP2009539909A priority Critical patent/JPWO2009060525A1/ja
Priority to PCT/JP2007/071714 priority patent/WO2009060525A1/ja
Publication of WO2009060525A1 publication Critical patent/WO2009060525A1/ja

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Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/10009—Improvement or modification of read or write signals
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/10009—Improvement or modification of read or write signals
    • G11B20/10046—Improvement or modification of read or write signals filtering or equalising, e.g. setting the tap weights of an FIR filter
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/10009—Improvement or modification of read or write signals
    • G11B20/10046—Improvement or modification of read or write signals filtering or equalising, e.g. setting the tap weights of an FIR filter
    • G11B20/10055—Improvement or modification of read or write signals filtering or equalising, e.g. setting the tap weights of an FIR filter using partial response filtering when writing the signal to the medium or reading it therefrom
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/10009—Improvement or modification of read or write signals
    • G11B20/10046—Improvement or modification of read or write signals filtering or equalising, e.g. setting the tap weights of an FIR filter
    • G11B20/10055—Improvement or modification of read or write signals filtering or equalising, e.g. setting the tap weights of an FIR filter using partial response filtering when writing the signal to the medium or reading it therefrom
    • G11B20/10175—PR4, PR(1,0,-1), i.e. partial response class 4, polynomial (1+D)(1-D)=(1-D2)
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/10009—Improvement or modification of read or write signals
    • G11B20/10268—Improvement or modification of read or write signals bit detection or demodulation methods
    • G11B20/10287—Improvement or modification of read or write signals bit detection or demodulation methods using probabilistic methods, e.g. maximum likelihood detectors
    • G11B20/10296—Improvement or modification of read or write signals bit detection or demodulation methods using probabilistic methods, e.g. maximum likelihood detectors using the Viterbi algorithm
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/455—Arrangements for functional testing of heads; Measuring arrangements for heads
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B2220/00—Record carriers by type
    • G11B2220/20—Disc-shaped record carriers
    • G11B2220/25—Disc-shaped record carriers characterised in that the disc is based on a specific recording technology
    • G11B2220/2508—Magnetic discs
    • G11B2220/2516—Hard disks

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Probability & Statistics with Applications (AREA)
  • Algebra (AREA)
  • Pure & Applied Mathematics (AREA)
  • Digital Magnetic Recording (AREA)
  • Signal Processing For Digital Recording And Reproducing (AREA)

Abstract

　評価対象とする磁気ヘッドの記録素子に、入力符号に応じて所定の記録周波数のＮＲＺＩの記録電流を流して記録媒体に磁気的に記録した後、磁気ヘッドの読出素子により記録媒体に記録された符号を磁気的に読み出す。読出符号はパーシャルレスポンス等化波形に波形等化され後、最尤検出によりパーシャルレスポンス畳込み符号が検出される。この最尤検出処理から磁気ヘッドの良否を判定するための尤度情報を生成して出力する。
PCT/JP2007/071714 2007-11-08 2007-11-08 磁気ヘッド評価方法、装置及び評価回路 WO2009060525A1 (ja)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2009539909A JPWO2009060525A1 (ja) 2007-11-08 2007-11-08 磁気ヘッド評価方法、装置及び評価回路
PCT/JP2007/071714 WO2009060525A1 (ja) 2007-11-08 2007-11-08 磁気ヘッド評価方法、装置及び評価回路

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2007/071714 WO2009060525A1 (ja) 2007-11-08 2007-11-08 磁気ヘッド評価方法、装置及び評価回路

Publications (1)

Publication Number Publication Date
WO2009060525A1 true WO2009060525A1 (ja) 2009-05-14

Family

ID=40625440

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2007/071714 WO2009060525A1 (ja) 2007-11-08 2007-11-08 磁気ヘッド評価方法、装置及び評価回路

Country Status (2)

Country Link
JP (1) JPWO2009060525A1 (ja)
WO (1) WO2009060525A1 (ja)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000156042A (ja) * 1998-11-18 2000-06-06 Fujitsu Ltd 信号処理装置及び信号処理方法及び情報記憶装置並びに情報再生装置
JP2001156865A (ja) * 1999-11-30 2001-06-08 Matsushita Electric Ind Co Ltd 受信品質測定装置
JP2004127495A (ja) * 2002-09-13 2004-04-22 International Manufacturing & Engineering Services Co Ltd ハード磁気ディスクまたは磁気ヘッドの試験方法
WO2006126256A1 (ja) * 2005-05-24 2006-11-30 Fujitsu Limited 磁気記録再生装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000156042A (ja) * 1998-11-18 2000-06-06 Fujitsu Ltd 信号処理装置及び信号処理方法及び情報記憶装置並びに情報再生装置
JP2001156865A (ja) * 1999-11-30 2001-06-08 Matsushita Electric Ind Co Ltd 受信品質測定装置
JP2004127495A (ja) * 2002-09-13 2004-04-22 International Manufacturing & Engineering Services Co Ltd ハード磁気ディスクまたは磁気ヘッドの試験方法
WO2006126256A1 (ja) * 2005-05-24 2006-11-30 Fujitsu Limited 磁気記録再生装置

Also Published As

Publication number Publication date
JPWO2009060525A1 (ja) 2011-03-17

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