Recording method and apparatus for digital signals in which lower order bits are separated into upper and lower side bits and separately recorded

• US 6,021,010 A
• Filed: 10/22/1998
• Issued: 02/01/2000
• Est. Priority Date: 03/21/1996
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nakata, Junichi, Sugita, Takehiro, Tajima, Mie
• Primary Examiner(s): Sniezek, Andrew L.
• Application Number:
  US09/177,006
• Time in Patent Office: 467 Days
• Field of Search: 360/22, 360/48, 360/32, 360/39, 360/57, 360/61, 360/64
• US Class Current: 360/22
• CPC Class Codes: G11B 15/125 conditioned by the operating function of the apparatus
• CPC Class Codes: G11B 15/1875 adaptations for special effects or editing signal processing or indexing therefor G11B27/00
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: G11B 20/1208 for continuous data, e.g. digitised analog information signals, pulse code modulated [PCM] data
• CPC Class Codes: G11B 2020/10592 specifically adapted for recording or reproducing multichannel signals
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 2220/913 Digital audio tape [DAT] format
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783
• CPC Class Codes: G11B 27/032 on tapes G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/036 Insert-editing
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 5/0086 using cyclically driven heads providing segmented tracks
• CPC Class Codes: G11B 5/09 Digital recording

Abstract

A recording/reproducing method for recording/reproducing digital signals on plural slanted tracks of a tape-shaped recording medium, in which, even if some of the slanted tracks are erased due to junction recording or after-recording, the signals can be reproduced satisfactorily. The input digital signals are divided into upper order bits and lower order bits, and the upper order bits are further divided into upper order side bits and lower order side bits. The data corresponding to the upper order bits, the data corresponding to the upper order side bits of the lower order bits and the data corresponding to the lower order side bits of the lower order bits are recorded in respective different slanted tracks.

Claims

1. A digital recording apparatus employing a tape-shaped recording medium having formed thereon a plurality of slanted tracks corresponding to digital information signals of two channels, comprising:

a signal processing unit for separating one of the two channels of the digital information signals into first upper order bits and first lower order bits and for separating the other channel of the digital signals into second upper order bits and second lower order bits, said signal processing unit separating said first lower order bits and said second lower order bits into respective upper order side bits and lower order side bits; and

a recording unit for recording an output of said signal processing unit on the tape-shaped recording medium, said recording unit having a rotary drum and at least one head mounted on said rotary drum, said recording unit causing said at least one head to record said first and second upper order bits, said upper order side bits of said first lower order bits, said upper order side bits of the second lower order bits, said lower order side bits of said first lower order bits and said lower order side bits of the second lower order bits from said signal processing unit as different tracks,

wherein said signal processing unit outputs the lower order side bits of said first lower order bits with a portion of the first upper order bits and the lower order side bits of said second lower order bits with a portion of the second upper order bits as one data, said recording unit causing said at least one head to record said one data on the tape-shaped recording medium to form a track.

2. The digital signal recording apparatus as claimed in claim 1 wherein said signal processing unit, when separating each channel of the two channels of the digital information signals into the first and second upper order bits and the first and second lower order bits, generates and appends a discrimination code for discriminating the first and second upper order bits and the first and second lower order bits from each other.

3. The digital signal recording apparatus as claimed in claim 1 wherein said signal processing unit outputs the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits as additional data, said recording unit causing said head to record said additional data on the tape-shaped recording medium to form a track.

4. The digital signal recording apparatus as claimed in claim 3 wherein said recording unit records data including the lower order side bits of said first lower order bits with a portion of said first upper order bits and said lower order side bits of the second lower order bits with a portion of the second upper order bits, data including the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits, and data including the first and second upper order bits in this order on the tape-shaped recording medium beginning from a leading end position of an interleaving block.

5. The digital signal recording apparatus as claimed in claim 1 wherein said signal processing unit includes an encoder for separating the digital signal into said first portion, second portion, upper order side bits and lower order side bits of said second portion and for generating said discrimination code, and a memory for recording an output of said encoder.

6. The digital signal recording apparatus as claimed in claim 5 wherein said signal processing unit includes an address generating unit for generating a write address and a readout address based on an interleaving period and a sampling word period used in said recording unit.

7. The digital signal recording apparatus as claimed in claim 1 further comprising:

a second head mounted on said rotary drum, said second head having an azimuth angle different from an azimuth angle of said at least one head, with tracks recorded using said at least one head on said tape-shaped recording medium being arrayed in alternation with and in partially overlapped relation to tracks recorded using said second head on said tape-shaped recording medium.

8. A digital signal recording/reproducing apparatus employing a tape-shaped recording medium having formed thereon a plurality of slanted tracks corresponding to digital information signals of two channels, comprising:

a first signal processing unit for separating one of the two channels of the digital information signals into first upper order bits and first lower order bits and for separating the other channel of the digital signals into second upper order bits and second lower order bits, said first signal processing unit separating said first lower bits and said second lower order bits into respective upper order side bits and lower order side bits;

a recording unit for recording an output of said first signal processing unit on the tape-shaped recording medium, said recording unit having a rotary drum and at least one head mounted on said rotary drum, said recording unit causing said at least one head to record said first and second upper order bits, said upper order side bits of said first lower order bits, upper order side bits of the second lower order bits, lower order side bits of said first lower order bits and lower order side bits of the second lower order bits from said first signal processing unit as different tracks; and

a second signal processing unit for re-arraying the upper order side bits of the first lower order bits, the upper order side bits of the second lower order bits, the lower order side bits of the first lower order bits and the lower order side bits of the second lower order bits in the signal read out by said at least one head for the first lower order bits and for the second lower order bits, and outputting the re-arrayed bits,

wherein said first signal processing unit outputs the lower order side bits of said first lower order bits with a portion of the first upper order bits and the lower order side bits of said second lower order bits with a portion of the second upper order bits as one data, said recording unit causing said at least one head to record said one data on the tape-shaped recording medium to form a track.

9. The digital signal recording/reproducing apparatus as claimed in claim 8 wherein said first signal processing unit, when separating each channel of the two channels of the digital signals into the first and second upper order bits and the first and second lower order bits, generates and appends a discrimination code for discriminating the first and second upper order bits and the first and second lower order bits from each other.

10. The digital signal recording/reproducing apparatus as claimed in claim 9 wherein said recording unit performs re-arraying based on said discrimination code.

11. The digital signal recording/reproducing apparatus as claimed in claim 9 wherein said recording unit records data including the lower order side bits of said first lower order bits with a portion of said first upper order bits and the lower order side bits of the second lower order bits with a portion of the second upper order bits, data including the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits, and data including the first and second upper order bits in this order on the tape-shaped recording medium beginning from a leading end position of an interleaving block;

and wherein, if, during reproduction, a relative speed between the at least one head and the tape-shaped recording medium is varied from that for normal reproduction, the first upper order bits and the second upper order bits of the data including the lower order side bits of said first lower order bits with a portion of said first upper order bits and the lower order side bits of the second lower order bits with a portion of the second upper order bits are read out.

12. The digital signal recording/reproducing apparatus as claimed in claim 8 wherein said first signal processing unit outputs the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits as additional data, said recording unit causing said at least one head to record said additional data on the tape-shaped recording medium to form a track.

13. The digital signal recording/reproducing apparatus as claimed in claim 12 wherein said first recording unit records data including the lower order side bits of said first lower order bits with a portion of said first upper order bits and the lower order side bits of the second lower order bits with a portion of the second upper order bits, data including the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits, and data including the first and second upper order bits in this order on the tape-shaped recording medium beginning from a leading end position of an interleaving block.

14. The digital signal recording/reproducing apparatus as claimed in claim 8 wherein said first signal processing unit includes an encoder for separating the digital signal into said first portion, second portion, upper order side bits and lower order side bits of said second portion and for generating said discrimination code, and a memory for recording an output of said encoder.

15. The digital signal recording/reproducing apparatus as claimed in claim 14 wherein said first signal processing unit includes an address generating unit for generating a write address and a readout address based on an interleaving period and a sampling word period used in said recording unit.

16. The digital signal recording/reproducing apparatus as claimed in claim 8 further comprising:

a second head mounted on said rotary drum, said second head having an azimuth angle different from that of said at least one head, with tracks recorded using said at least one head on said tape-shaped recording medium being arrayed in alternation with and in partially overlapped relation to tracks recorded using said second head on said tape-shaped recording medium.

17. A digital signal recording method employing a tape-shaped recording medium having formed thereon a plurality of slanted tracks corresponding to digital information signals of two channels, comprising:

separating one of the two channels of the digital information signals into first upper order bits and first lower order bits and for separating the other channel of the digital signals into second upper order bits and second lower order bits;

separating said first lower order bits and said second lower order bits into respective upper order side bits and lower order side bits; and

recording, by at least one head mounted on a rotary drum, said first and second upper order bits, said upper order side bits of said first lower order bits, the upper order side bits of the second lower order bits, the lower order side bits of said first lower order bits and the lower order side bits of the second lower order bits from said signal processing unit as different tracks,

wherein said step of recording includes recording the lower order side bits of said first lower order bits with a portion of the first upper order bits and the lower order side bits of said second lower order bits with a portion of the second upper order bits as one data, said recording unit causing said at least one head to record said one data on the tape-shaped recording medium to form a track.

18. The digital signal recording method as claimed in claim 17 wherein, when separating the digital signals of the two channels into the first and second upper order bits and the first and second lower order bits, a discrimination code for discriminating the first and second upper order bits and the first and second lower order bits is generated and appended to the upper order bits and to the lower order bits.

19. The digital signal recording method as claimed in claim 17 wherein the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits are recorded as additional data on the tape-shaped recording medium to form a track thereon.

20. The digital signal recording method as claimed in claim 19 wherein data including the lower order side bits of said first lower order bits with a portion of said first upper order bits and the lower order side bits of the second lower order bits with a portion of the second upper order bits, data including the upper order side bits of the first lower order bits and the upper order side bits of the second lower order bits, and data including the first and second upper order bits are recorded in this order on the tape-shaped recording medium beginning from a leading end position of an interleaving block.

21. The digital signal recording method as claimed in claim 17 wherein tracks recorded using a second head mounted on said rotary drum with an azimuth angle different from that of the head on said tape-shaped recording medium is arrayed in alternation with an in partially overlapped relation to tracks recorded using said at least one head on said tape-shaped recording medium.