Arrangement for recording clock run-in codewords at the beginning of a track on a magnetic record carrier

- U.S. Philips Corporation

In a helical seen recorder, a sequence of n-bit first codewords (W.sub.1) and n-bit second codewords (W.sub.2) if any, are stored in second track parts (TP2) which form the beginning of the tracks (T.sub.1, T.sub.2 . . . ), these codewords having a form so that both a PR1 detection and a PR4 detection is possible on reproduction. The second codewords are the inverses of the first codewords. An optional form of the first codeword may be: 0001110001110000011100011.

Skip to:  ·  Claims  ·  References Cited  · Patent History  ·  Patent History

Claims

1. Arrangement for recording a digital signal in tracks on a magnetic record carrier, said tracks running parallel with each other over said record carrier and at an angle relative to the longitudinal axis of said record carrier, while the digital signal is recorded in a first track part of the tracks, said arrangement comprising an input terminal for receiving the digital signal, and recording means for recording the digital signal in the first track part, characterized in that the arrangement further comprises codeword generating means for generating n-bit first codewords, and in that the recording means is arranged for recording the n-bit first codewords in second track pars which form the beginning of the tracks, in that the first codewords each contain a sequence of, successively, p bits having a first binary value, q bits having a second binary value being the inverse binary value of the first binary value, and r bits having the first binary value, and in that p, q and r are odd integers for which the following holds p.gtoreq.3, q.gtoreq.3, and r.gtoreq.3.

2. Arrangement as claimed in claim 1, characterized in that the arrangement is furthermore arranged for generating n-bit second codewords and for recording the second codewords in the second track parts, and in that the second codewords are the inverse codewords of the first codewords.

3. Arrangement as claimed in claim 1, characterized in that r is equal to p.

4. Arrangement as claimed in claim 3, characterized in that the first codewords contain a sequence of successive p bits having the fist binary value, q bits having the second binary value, p bits having the first binary value and again q bits having the second binary value.

5. Arrangement as claimed in claim 1, characterized in that the first codewords additionally contain p+2 successive bits of the first binary value.

6. Arrangement as claimed in claim 1, characterized in that the first codewords additionally contain q+2 successive bits of the second binary value.

7. Arrangement as claimed in claim 1, characterized in that p, q and r are equal to 3 or 5.

8. Arrangement as claimed in claim 2, characterized in that for generating a pilot signal in the information recorded in the second track parts, said pilot signal consisting of a carrier having a relatively low frequency with respect to the frequency of the recorded information, the arrangement is arranged for alternately recording the first codewords and the second codewords in the second track parts so that the mean value of the recorded information in essence varies with the variation of the relatively low-frequency carrier.

9. Arrangement as claimed in claim 8, characterized in that for this purpose the disparity of the first and second codewords is unequal to zero.

10. Arrangement as claimed in claim 1, characterized in that n=25.

11. Arrangement as claimed in claim 10, characterized in that the first codeword is equal to the 25-bit binary number "0001110001110000011100011"..Iadd.

12. Arrangement for recording a digital signal in tracks on a magnetic record carrier, said tracks running parallel with each other over said record carrier and at an angle relative to the longitudinal axis of said record carrier while the digital signal is recorded in a first track part of the tracks, said arrangement comprising an input terminal for receiving the digital signal, and recording means for recording the digital signal in the first track part, characterized in that the arrangement further comprises codeword generating means for generating n-bit first codewords, and in that the recording means is arranged for recording the n-bit first codewords in second track parts, in that the first codewords each contain a sequence of, successively, p bits having a first binary value, q bits having a second binary value being the inverse binary value of the first binary value, and r bits having the first binary value, and in that p, q and r are odd integers for which the following holds p.gtoreq.3, q.gtoreq.3, and r.gtoreq.3..Iaddend..Iadd.13. Arrangement as claimed in claim 12, for recording a first digital signal in the first track parts and for recording a second digital signal in third track parts in the tracks, characterized in that the recording means is arranged for recording the second track parts in between the first and the third track parts..Iaddend..Iadd.14. Arrangement as claimed in claim 13, characterized in that the arrangement is furthermore arranged for generating n-bit second codewords and for recording the second codewords in the second track parts, an in that the second codewords are the inverse codewords of the first codewords..Iaddend..Iadd.15. Arrangement as claimed in claim 13, characterized in that r is equal to p..Iaddend..Iadd.16. Arrangement as claimed in claim 15, characterized in that the first codewords contain a sequence of successive p bits having the first binary value, q bits having the second binary value, p bits having the first binary value, and again q bits having the second binary value..Iaddend..Iadd.17. Arrangement as claimed in claim 13, characterized in that the first codewords additionally contain p+2 successive bits of the first binary value..Iaddend..Iadd.18. Arrangement as claimed in claim 13, characterized in that the first codewords additionally contain q+2 successive bits of the second binary value..Iaddend..Iadd.19. Arrangement as claimed in claim 13, characterized in that p, q and r are equal to 3 or 5..Iaddend..Iadd.20. Arrangement as claimed in claim 14, characterized in that for generating a pilot signal in the information recorded in the second track parts, said pilot signal consisting of a carrier having a relatively low frequency with respect to the frequency of the recorded information, the arrangement is arranged for alternately recording the first codewords and the second codewords in the second track parts so that the mean value of the recorded information in essence varies with the variation of the relatively low-frequency carrier..Iaddend..Iadd.21. Arrangement as claimed in claim 20, characterized in that for this purpose, the disparity of the first and second codewords is unequal to zero..Iaddend..Iadd.22. Arrangement as claimed in claim 13, characterized in that n=25..Iaddend..Iadd.23. Arrangement as claimed in claim 22, characterized in that the first codeword is equal to the 25-bit binary number "0001110001110000011100011"..Iaddend..Iadd.24. A method recording a digital signal in tracks on a magnetic record carrier, said tracks running parallel with each other over said record carrier and at an angle relative to the longitudinal axis of said record carrier, while the digital signal is recorded in a first track part of the tracks, said method comprising the steps:

receiving the digital signal; and
recording the digital signal in the first track part, characterized in that the method further comprises the steps:
generating n-bit first codewords; and
recording the n-bit first codewords in second track parts, in that the first codewords each contain a sequence of, successively, p bits having a first binary value, q bits having a second binary value being the inverse binary value of the first binary value, and r bits having the first binary value, and in that p, q and r are odd integers for which the following

holds p.gtoreq.3, q.gtoreq.3, and r.gtoreq.3..Iaddend..Iadd.25. A method as claimed in claim 24, for recording a first digital signal in the first track parts, wherein said method further comprises the steps:

recording a second digital signal in third track parts in the tracks; and
recording the second track parts in between the first and the third track parts..Iaddend..Iadd.26. A method as claimed in claim 24, characterized in that the method further comprises the steps:
generating n-bit second codewords; and
recording the second codewords in the second track parts, and in that the second codewords are the inverse codewords of the first codewords.

.Iaddend..Iadd.27. A method as claimed in claim 25, characterized in that the method further comprises the steps:

generating n-bit second codewords; and
recording the second codewords in the second track parts, and in that the second codewords are the inverse codewords of the first codewords..Iaddend..Iadd.28. A method as claimed in claim 25, characterized in that r is equal to p..Iaddend..Iadd.29. A method as claimed in claim 28, characterized in that the first codewords contain a sequence of successive p bits having the first binary value, q bits having the second binary values, p bits having the first binary value, and again q bits having the second binary value..Iaddend..Iadd.30. A method as claimed in claim 25, characterized in that the first codewords additionally contain p+2 successive bits of the first binary value..Iaddend..Iadd.31. A method as claimed in claim 25, characterized in that the first codewords additionally contain q+2 successive bits of the second binary value..Iaddend..Iadd.32. A method as claimed in claim 25, characterized in that

p, q and r are equal to 3 or 5..Iaddend..Iadd.33. A method as claimed in claim 27, characterized in that for generating a pilot signal in the information recorded in the second track parts, said pilot signal consisting of a carrier having a relatively low frequency with respect to the frequency of the recorded information, the method comprises the step:

alternately recording the first codewords and the second codewords in the second track parts so that the mean value of the recorded information in essence varies with the variation of the relatively low-frequency carrier..Iaddend..Iadd.34. A method as claimed in claim 33, characterized in that for this purpose, the disparity of the first and second codewords is unequal to zero..Iaddend..Iadd.35. A method as claimed in claim 25, characterized in that n=25..Iaddend..Iadd.36. A method as claimed in claim 35, characterized in that the first codeword is equal to the 25-bit binary number "0001110001110000011100011"..Iaddend..Iadd.37. A record carrier having a digital signal recorded thereon in tracks, said tracks running parallel with each other over said record carrier and at an angle relative to a longitudinal axis of said record carrier, while the digital signal is recorded in a first track part of the tracks, said digital signal being recorded in the first track part, characterized in that the record carrier further comprises n-bit first codewords recorded in second track parts, the first codewords each containing a sequence of, successively, p bits having a first binary value, q bits having a second binary value being the inverse binary value of the first binary value, and r bits having the first binary value, and in that p, q and r are odd integers for which the following holds p.gtoreq.3, q.gtoreq.3, and r.gtoreq.3..Iaddend..Iadd.38. A record carrier as claimed in claim 37, having a first digital signal recorded in the first track parts and a second digital signal recorded in third track parts in the tracks, the second track parts being arranged in between the first and the third track parts..Iaddend..Iadd.39. A record carrier as claimed in claim 37, characterized in that the record carrier further comprises n-bit second codewords recorded in the second track parts, the second codewords being the inverse codewords of the first codewords..Iaddend..Iadd.40. A record carrier as claimed in claim 38, characterized in that the record carrier further comprises n-bit second codewords recorded in the second track parts, the second codewords being the inverse codewords of the first

codewords..Iaddend..Iadd.41. A record carrier as claimed in claim 38, characterized in that r is equal to p..Iaddend..Iadd.42. A record carrier as claimed in claim 41, characterized in that the first codewords contain a sequence of successive p bits having the first binary value, q bits having the second binary value, p bits having the first binary value, and again q bits having the second binary value..Iaddend..Iadd.43. A record carrier as claimed in claim 38, characterized in that the first codewords additionally contain p+2 successive bits of the first binary value..Iaddend..Iadd.44. A record carrier as claimed in claim 38, characterized in that the first codewords additionally contain q+2 successive bits of the second binary value..Iaddend..Iadd.45. A record carrier as claimed in claim 38, characterized in that p, q and r are equal to 3 or 5..Iaddend..Iadd.46. A record carrier as claimed in claim 40, characterized in that for generating a pilot signal in the information recorded in the second track parts, said pilot signal consisting of a carrier having a relatively low frequency with respect to the frequency of the recorded information, the first codewords and the second codewords are alternately recorded in the second track parts so that the mean value of the recorded information in essence varies with the variation of the relatively low-frequency carrier..Iaddend..Iadd.47. A record carrier as claimed in claim 46, characterized in that for this purpose, the disparity of the first and second codewords is unequal to zero..Iaddend..Iadd.48. A record carrier as claimed in claim 38, characterized in that n=25..Iaddend..Iadd.49. A record carrier as claimed in claim 48, characterized in that the first codeword is equal to the 25-bit binary number "0001110001110000011100011"..Iaddend.

Referenced Cited
U.S. Patent Documents
4390801 June 28, 1983 Kurata et al.
4851837 July 25, 1989 Baldwin
4855742 August 8, 1989 Verboom
5128811 July 7, 1992 Van Gestel
5136436 August 4, 1992 Kahlman
5142421 August 25, 1992 Kahlman et al.
Patent History
Patent number: RE36096
Type: Grant
Filed: Apr 26, 1995
Date of Patent: Feb 16, 1999
Assignee: U.S. Philips Corporation (New York, NY)
Inventor: Wilhelmus J. Van Gestel (Eindhoven)
Primary Examiner: Ali Neyzari
Attorney: Edward W. Goodman
Application Number: 8/429,363
Classifications
Current U.S. Class: In Specific Code Or Form (360/40); Data In Specific Format (360/48); 375/19
International Classification: G11B 509;