KR20030010322A - Optical recording medium on which wobble signal having header information is recorded, method and apparatus for recording the wobble signal, method and apparatus for reproducing the wobble signal - Google Patents

Abstract

PURPOSE: An information recording medium in which a wobble signal including header information is recorded, an apparatus and a method for recording the wobble signal, a reproducing apparatus and method are provided to record larger amount of user data, extract header information and obtain a stable clock signal. CONSTITUTION: An information recording medium includes a track on which user data is recorded, and a wobble signal recorded in the track. The wobble signal includes header information. The header information corresponds to digital data having the first level represented in the basic wave of a sine wave and the second level represented in a composite wave obtained by adding up the basic wave and at least one harmonics. An apparatus for recording the wobble signal includes a wobble signal generator(4) and a recording unit(5). The wobble signal generator generates the wobble signal including the header information. The recording unit records the wobble signal in the information recording medium.

Description

Optical recording medium on which wobble signal having header information is recorded, method and apparatus for recording the wobble signal, method and apparatus for reproducing the wobble signal}

The present invention relates to an information recording medium, and more particularly, to an information recording medium having a wobble track on which a wobble signal is recorded, a wobble signal recording method, a recording device, a wobble signal reproducing method, and a reproducing device.

In a recordable optical disc such as a DVD-RAM (Digital Versatile Disc-RAM), concentric or spiral tracks (groove tracks or land tracks) are formed. A wobble signal is recorded in the track using a change in the amplitude direction. The track on which the wobble signal is recorded is called a wobble track. The wobble signal may be used as a means for recording an auxiliary clock signal for obtaining synchronization information during recording / reproducing. That is, the wobble signal has a frequency of a band which does not affect the tracking servo mechanism provided in the recording / reproducing apparatus, and is used as an auxiliary clock signal to assist the system clock.

User data is recorded on the wobble track by the pickup apparatus. In order to record the user data through the laser beam, the pickup device provided in the recording apparatus and oscillating the recording laser should be able to move to a desired position. For this purpose, addressing information is recorded on the optical disc to enable the pickup apparatus to move to a desired position. Here, the "addressing information" refers to "identification information given to each unit recording block when the information track is divided into a plurality of unit recording blocks."

A typical method of recording addressing information on a conventional optical disc is to form a header area separately from a track on which user data is recorded and to record the addressing information therein.

1 is a schematic diagram of a conventional optical disk.

Referring to Fig. 1, a track (land track and / or groove track) which is a user data area is formed on an optical disc, and a header area in which header information is recorded as a pre-pit is provided separately from the track. The header area is arranged in a predetermined area of a sector (unit recording block), and the pickup device provided in the recording / reproducing apparatus can easily move to a desired position through the addressing information recorded in the header area. Further, the sector number, sector type, information track, etc. recorded in the header area can be recognized, and servo control can be performed.

The header information recording method according to the 1999 DVD RAM standard version 2.0 is CAPA (Complementary Allocated Pit Address) method. As shown in FIG. 1, the CAPA method records four header information in one sector, but records two sets of two tracks each shifted by 1/2 track from the center of the information track.

However, providing a separate header area not only complicates the optical disc manufacturing process but also requires additional circuitry to compensate for the wobble signal being not properly obtained while the pickup apparatus passes through the header area. Furthermore, when the demand for high density recording media is increasing as the use of multimedia contents becomes more common, providing a separate header area results in narrowing the area where user data can be recorded.

It is therefore an object of the present invention to provide an information recording medium, a wobble signal recording method, a recording device, a wobble signal reproducing method and a reproducing apparatus capable of recording more user data.

Another object of the present invention is an information recording medium having a wobble signal recorded therein capable of extracting header information and obtaining a more stable clock signal, a wobble signal recording method, a recording device, a wobble signal reproducing method, and a reproducing apparatus. To provide.

1 is a schematic diagram of a conventional optical disk,

2 is a schematic diagram of an information recording medium according to a preferred embodiment of the present invention;

3a and 3b are examples of the formation of the information track of FIG.

4 is a block diagram of a wobble signal recording apparatus according to the present invention;

FIG. 5 is a detailed block diagram according to the first embodiment of the wobble signal recording apparatus of FIG. 4;

6 is a schematic diagram of signals generated by the carrier signal generator 42 of FIG.

7 is a spectral diagram of the signals shown in FIG. 6;

8 is an exemplary diagram of an edge-modulated wobble signal using the signals shown in FIGS. 6A and 6B;

9 is a flowchart for explaining a wobble signal recording method according to a first embodiment of the present invention;

10 is a detailed block diagram according to a second embodiment of the wobble signal recording apparatus of FIG. 4;

11 is a schematic diagram of each signal generated from the wobble signal generation unit 4 of FIG.

12 is a flowchart for explaining a wobble signal recording method according to a second embodiment of the present invention;

13 and 14 are reference diagrams for explaining another example of a wobble signal according to the present invention;

15 is an example of addressing information of a header information section in which a wobble signal is recorded according to the present invention;

16 is a block diagram of a playback apparatus according to the present invention;

17 is an embodiment of FIG. 16;

18 is a waveform diagram of each signal detected from the playback device of FIG. 17;

19 is a flowchart for explaining a header information reproducing method according to the present invention;

20 is a flowchart for describing a method for extracting header information according to an embodiment of the present invention.

The object includes: a wobble signal including first header information formed of a fundamental wave of a sinusoidal wave and a second level formed of a synthesized wave obtained by adding the fundamental wave and at least one harmonic; And a wobble track in which user data is recorded and the wobble signal is recorded. Here, the harmonics are preferably the 2n + 1 harmonics (n is a positive integer) of the sine wave.

More specifically, the object may include a wobble signal including first header information of a first level of digital data represented by a fundamental wave of a sinusoidal wave and a second level of first header information represented by a combined wave of the fundamental wave and a third harmonic; And a wobble track in which user data is recorded and the wobble signal is recorded. Here, the difference X between the magnitude A of the spectrum of the fundamental wave and the magnitude B of the spectrum of the synthesized wave is preferably less than 30 dB.

The wobble signal may be a single frequency signal, and second header information may be phase-modulated in at least a portion of a section in which the first header information is loaded.

More preferably, the second header information is amplitude-modulated on at least a portion of the section in which the first header information is loaded.

On the other hand, according to another aspect of the present invention, the above object is an apparatus for recording a wobble signal on an information recording medium, wherein a first level of digital data is represented by a fundamental wave of a sinusoidal wave and a second level of the fundamental wave and at least one harmonic wave. A wobble signal generation unit configured to generate a wobble signal including first header information indicated by the combined wave; And a recording unit for recording the wobble signal generated by the wobble signal generating unit on the information recording medium.

The wobble signal generation unit includes a sine wave and a sine wave generator for generating harmonics of the sine wave; A fundamental wave of the generated sinusoidal wave and an edge-modulator for generating a synthesized wave by combining the fundamental wave and at least one second n + 1 harmonic and modulating header information using the generated fundamental wave and the synthesized wave (n Is a positive integer).

The edge-modulator modulates the header information into an analog signal by respectively corresponding the fundamental and synthesized waves to first and second levels of digital data.

In addition, the above object is an apparatus for recording a wobble signal on an information recording medium, wherein a first level of digital data is represented by a fundamental wave of a sine wave and a second level is represented by a sum of the fundamental wave and at least one harmonic wave. A wobble signal generation unit configured to generate a wobble signal having a single frequency including information and phase-modulated second header information; And a recording unit for recording the wobble signal generated by the wobble signal generating unit on the information recording medium.

The wobble signal generator includes a sine wave generator for generating the fundamental and synthesized waves; An edge-modulator for edge-modulating the first header information using the fundamental and synthesized waves; A phase-modulator for phase-modulating the second header information using the fundamental or synthesized waves; And a signal synthesizer for synthesizing the edge-modulated signal output from the edge-modulator and the phase-modulated signal output from the phase-modulator and outputting the single frequency wobble signal.

On the other hand, the object of the present invention is a method for recording a wobble signal on an information recording medium, comprising: (a) generating a fundamental wave of a sinusoidal wave and generating a synthesized wave by adding the fundamental wave and at least one harmonic of the sinusoidal wave; (b) generating a single frequency wobble signal containing edge-modulated header information using the fundamental wave and the synthesized wave; And (c) recording the generated single frequency wobble signal.

Step (a) may include: (a1) generating the synthesized wave by adding the fundamental wave and at least one second n + 1 harmonic of the fundamental wave; And (b2) edge-modulating the header information using the fundamental wave and the synthesized wave (n is a positive integer).

Preferably, the step (b2) corresponds to the first and second levels of digital data and modulates the fundamental and synthesized waves into analog signals.

In addition, the object is a method for recording a wobble signal on an information recording medium, comprising: (a) generating a fundamental wave of a sinusoidal wave and a synthesized wave obtained by synthesizing at least one harmonic of the fundamental wave and the sinusoidal wave; (b) generating a single frequency wobble signal including edge-modulated first header information and phase-modulated second header information using the generated fundamental and synthesized waves; And (c) recording the generated single frequency wobble signal.

The step (b) may include (b1) generating an edge-modulated signal by modulating the first header information by corresponding the fundamental and synthesized waves to first and second levels of digital data, respectively; (b2) phase-modulating the second header information; And (b3) synthesizing the single frequency wobble signal by overlapping the edge-modulated signal with the phase-modulated signal.

On the other hand, according to another aspect of the present invention, the above object is a method for reproducing header information from a wobble signal recorded on an information recording medium, wherein (a) the first level of digital data is represented by a fundamental wave of a sine wave and the second level. Reading a wobble signal of a single frequency carrying header information indicated by the sum of the fundamental and at least one harmonic; And (b) multiplying the read wobble signal by a predetermined sine wave to extract the header information.

The step (b) is preferably a step of extracting the header information by multiplying the wobble signal by a signal obtained by passing the wobble signal through a PLL (Phased Locked Loop).

Step (b) may include: (b21) generating a clock signal based on the wobble signal; (b22) generating a sine wave and outputting it in synchronization with the clock signal; And (b23) multiplying the output sinusoid by the wobble signal to extract the header information.

The above object is also an apparatus for reproducing header information from a wobble signal recorded on an information recording medium, wherein a first level of digital data is represented by a fundamental wave of a first sinusoidal wave and a second level is said fundamental wave and at least one harmonic wave. A detector for detecting a wobble signal having a single frequency on which header information indicated by the sum is loaded; A sinusoidal wave generator generating a second sinusoidal wave; And a header information extracting unit for extracting the header information by multiplying the wobble signal detected by the detecting unit with the second sinusoidal wave generated by the sinusoidal wave generating unit.

The header information extracting unit multiplies the detected wobble signal by the second sinusoidal wave; A rectifier for rectifying the signal output from the multiplier; The filter may include a low pass filter (LPF) for filtering a signal output from the rectifier to output a signal in which the header information is represented as digital data. The reproduction apparatus further includes a band pass filter (BPF) for removing noise from the signal output from the detector and outputting the noise to the multiplier, wherein the order of the band of the band pass filter is higher than the order of the low pass filter. More preferred.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

2 is a schematic diagram of an information recording medium according to a preferred embodiment of the present invention.

Referring to Fig. 2, a track (groove track / land track) of concentric circles a or spirals b is formed in the optical disk according to the present embodiment. The wobble signal is recorded in the track. The wobble signal is one of means for recording an auxiliary clock signal for obtaining synchronization information during recording / reproducing. The wobble signal has a frequency of a band which does not affect the tracking servo mechanism provided in the recording / reproducing apparatus and is used as an auxiliary clock signal to assist the system clock.

3A and 3B are examples of formation of the information track of FIG.

As shown, the wobble signal adds a certain amount of offset to the left and right sides of the laser beam when recording the groove track using the laser beam in the process of manufacturing the substrate of the optical disk, that is, the mastering process. It is recorded by changing the shape on both side walls of the groove track. Referring to FIG. 3A, the wobble signal is recorded on both wall surfaces of the groove track, and in FIG. 3B, the wobble signal is recorded only on one wall surface of the groove track. As such, the wobble signal according to the present invention may be recorded on one side or both side walls of the track as needed.

4 is a block diagram of a wobble signal recording apparatus according to the present invention.

Referring to FIG. 4, the wobble signal recording apparatus includes a wobble signal generation unit 4 and a recording unit 5. The wobble signal generator 4 generates a wobble signal according to the present invention. That is, a single frequency wobble signal containing the header information is generated by edge-modulating the header information using the fundamental wave of the sine wave and the synthesized wave of the fundamental wave and at least one harmonic wave. Edge-modulation is described below.

The recording unit 5 records the wobble signal generated by the wobble signal generation unit 4 on the information recording medium 400. To this end, the recording unit 5 is provided with a pickup device provided with a laser diode capable of oscillating a laser beam.

FIG. 5 is a detailed block diagram of the wobble signal recording apparatus of FIG.

Referring to Fig. 5, the wobble signal generator 4 of the wobble signal recording apparatus includes a sine wave generator 42 and an edge-modulator 43. The sinusoidal wave generator 42 generates a fundamental wave and a harmonic of the sinusoidal wave, and generates a synthesized wave by synthesizing the generated sinusoidal wave and at least one harmonic. The synthesized wave is obtained by adding the fundamental wave of the sinusoidal wave and at least one of the first harmonic wave, the second harmonic wave, the third harmonic wave, and the odd-numbered harmonic wave. Accordingly, the fundamental wave and the synthesized wave have the same frequency but have different edge waveforms. The edge-modulator 43 uses edge-modulated header information by using the fundamental and synthesized waves generated from the sinusoidal wave generator 42. do. On the other hand, the header information includes addressing information.

FIG. 6 is a schematic diagram of fundamental and synthesized waves generated by the sinusoidal wave generator 42 of FIG. 5.

6 (a) shows a synthesized wave, and (b) shows a fundamental wave. As shown, the synthesized wave and the fundamental wave have the same frequency but different edge waveforms. If there is a pure wobble section in which no header information is included in the wobble signal, the pure wobble section may be displayed as a fundamental wave or a synthesized wave.

Sinusoidal harmonics are theoretically generated indefinitely. Harmonics are signals having an integer multiple of the frequency of the fundamental wave. When the frequency of the fundamental wave is ω, a signal having a frequency of 2ω is a second harmonic, and a signal having a frequency of 3ω is a third harmonic, a frequency of nω. The signal with n is called the nth harmonic. The square wave is represented by the infinite sum of the sine wave fundamental wave and the (2n + 1) harmonic wave (n is a positive integer).

If the high level is displayed as a fundamental wave, the low level is represented by a square wave, which is more preferable in terms of easier discrimination between high and low levels of digital data, that is, decoding of header information. However, recordable information recording media use signals in the RF band as recording signals. In other words, an RF band signal is used as a signal for forming a pit for recording user data in a land track or groove track. Therefore, when the synthesized wave includes a signal in the RF band, interference with the recording signal is problematic. In order to prevent this, in the present invention, a synthesized wave is obtained by adding a fundamental wave and a finite odd-numbered harmonic.

FIG. 7 is a spectral diagram of the signal a shown in FIG. 6. (A) shows the spectrum of the fundamental wave for synthesizing a signal having a trapezoidal waveform, and (B) shows the spectrum of the third harmonic. As the difference between the spectra of the two signals increases, that is, when the spectrum of the third harmonic becomes significantly smaller than that of the fundamental wave, the signal having the trapezoidal waveform is changed into a signal close to the sine wave. As described above, the signal having the trapezoidal waveform is preferably closer to the square wave from the detection side of the header information, and less preferably the closer to the sine wave. Therefore, the difference between the magnitude of the spectrum of the third harmonic and the spectrum of the fundamental wave should be at least 30 dB. This is expressed as follows.

X = A-B, A or B = 20log [10 (spectrum size)]

On the other hand, as the number of harmonics added to obtain the synthesized wave increases, more high frequency components are included, which increases the possibility of invading the RF band of the recording signal for recording user data. For this reason, the pure wobble interval is more preferably represented by the fundamental wave.

FIG. 8 is an exemplary diagram of an edge-modulated wobble signal using the signals shown in FIGS. 6A and 6B.

Referring to FIG. 8, when the header information bit string in which the header information is represented by digital data is "10101010", the high level "1" corresponds to (a) and the low level "0" corresponds to (b). That is, it can be seen that the wobble signal according to the present embodiment is an edge-modulated signal based on a signal having a trapezoidal waveform of FIG. 6 (synthetic wave) and a sine wave (basic wave).

The wobble signal recording method according to the first embodiment of the present invention will be described below based on the above configuration.

9 is a flowchart for explaining a wobble signal recording method according to the first embodiment of the present invention.

The sinusoidal wave generator 42 generates a fundamental wave of the sinusoidal wave in step 901. Next, the sinusoidal wave generator 42 generates at least one harmonic for the sinusoidal wave and generates the synthesized wave by adding the generated harmonics and the fundamental wave (step 902). The edge modulator 43 generates a wobble signal including the edge-modulated header information by using the fundamental wave and the synthesized wave provided from the sinusoidal wave generator 42 (step 903). The recording unit 5 records the generated wobble signal on the optical disk 400 (step 904).

FIG. 10 is a detailed block diagram of a wobble signal recording apparatus of FIG.

Referring to FIG. 10, the wobble signal generator 4 of the wobble signal recording apparatus includes a sine wave generator 92, an edge-modulator 93, a phase-modulator 94, and a signal synthesizer 95. Equipped. The sinusoidal wave generator 92 generates a fundamental wave and a harmonic of the sinusoidal wave, and generates a synthesized wave by synthesizing the generated sinusoidal wave and at least one harmonic. The synthesized wave is obtained by adding the fundamental wave of the sinusoidal wave and at least one of the first harmonic wave, the second harmonic wave, the third harmonic wave, and the odd-numbered harmonic wave. Thus, the fundamental wave and the synthesized wave have the same frequency but different edge waveforms. The edge modulator 43 edge-modulates the header information by using the fundamental wave and the synthesized wave generated from the sinusoidal wave generator 42. The edge modulator 93 receives the first header information and performs edge-modulation using the fundamental wave and the synthesized wave. The phase-modulator 94 receives the second header information and phase-modulates the fundamental wave or the synthesized wave. The signal synthesizer 95 synthesizes the edge-modulated signal and the phase-modulated signal to generate a wobble signal according to the present embodiment. The recording unit 5 records the generated wobble signal on the optical disk 400. Here, the first and second header information includes addressing information. As such, since the first and second header information can be carried in the same section, more header information can be recorded. That is, since the density of the header information carried on the wobble signal is increased, the header information section can be reduced. When the header information section of the wobble signal is reduced and the pure wobble section composed of sine waves increases, there is an advantage that the clock signal can be detected more stably. In addition, when at least some of the first and second header information are configured with the same information, the same information is repeatedly recorded, thereby reducing an error that may occur when the header information is reproduced.

FIG. 11 is a schematic diagram of each signal generated from the wobble signal generator 4 of FIG.

Referring to FIG. 11, (a) shows an edge-modulated signal edge-modulated by the edge-modulator 93 when the first header information bit string in which the first header information is represented as a digital signal is "101". . (b) shows a phase-modulated signal phase-modulated by the phase-modulator 94 when the second header information bit string indicated by the second header information as a digital signal is " 011 ". From (c), the signal synthesizing unit 95 can confirm the wobble signal obtained by combining the edge-modulation signal for the first header information bit string "101" and the phase-modulation signal for the second header information bit string.

The wobble signal recording method according to the second embodiment of the present invention will be described below based on the above configuration.

12 is a flowchart for explaining a wobble signal recording method according to a second embodiment of the present invention.

Referring to FIG. 12, the sinusoidal wave generator 92 generates a fundamental wave of a sinusoidal wave in step 1201. Next, the sinusoidal wave generator 92 generates at least one harmonic for the sinusoidal wave, and generates a synthesized wave by adding the generated harmonics and the fundamental wave (step 1202). The edge modulator 93 receives the first header information and performs edge-modulation using the fundamental wave and the synthesized wave (step 1203). The phase-modulator 94 receives the second header information and phase-modulates the fundamental wave or the synthesized wave (step 1204). The signal combiner 95 synthesizes the edge-modulated signal a and the phase-modulated signal b to generate a wobble signal c of a single frequency according to the present embodiment. The recording unit 5 records the generated wobble signal on the optical disk 400 (step 1106).

13 and 14 are reference diagrams for explaining another example of the wobble signal according to the present invention.

Referring to FIG. 13, (a) shows an edge-modulated signal of which the first header information bit string is edge-modulated, and (b) shows a phase-modulated signal of which the second header information bit string is phase-modulated. In FIG. 3, a modulated signal obtained by modulating the third header information bit string is illustrated. The modulation signal in (c) is represented by a sine wave having the same waveform and frequency as the high level "1" and the low level "0", but some sections of the high level "1" have a difference of zero amplitude. That is, the number of repetitions of the circumferential waveform of "1" and "0" differs from each other. (d) shows a wobble signal obtained by combining the edge-modulated signal of (a), the phase-modulated signal of (b), and the modulation signal of (c). As such, since the first, second and third header information is carried in the same section, more header information can be recorded. Accordingly, as in the case of FIG. 11, the header information section of the wobble signal can be reduced. In addition, when at least a part of the first, second or third header information is the same, an error rate during reproduction of the header information is lowered.

Referring to FIG. 14, (a) shows an edge-modulated signal of which the first header information bit string is edge-modulated, and (b) shows a modulated signal of which the second header information bit string is modulated. (c) shows a wobble signal obtained by combining the edge-modulated signal of (a) and the modulated signal of (b). Similarly, since the first and second header information are carried in the same section, more header information can be recorded. Furthermore, as in the case of FIG. 11, when at least a part of the first and second header information are the same, an error rate when reproducing header information is lowered.

15 is an example of addressing information {PID (Physical Identification Data Structure) structure of a header information section in which a wobble signal is recorded according to the present invention.

Referring to FIG. 15, an optical disc according to the present embodiment includes header information including four header fields in one error correction code (ECC) block (implemented by 64 KB or 32 KB in this embodiment). The wobble signal is recorded. Each header field may include synchronization data for detecting an identifier ID, a PID storing addressing information for each sector, and an IED (ID ErrorDetection) storing error detection information of the identifier ID.

16 is a block diagram of a header information reproducing apparatus according to the present invention.

Referring to FIG. 16, the header information reproducing apparatus includes a reading unit 61, a sine wave generating unit 63, and a header information extracting unit 64. The reading unit 61 reads the wobble signal from the optical disc 600. The read wobble signal is a single frequency signal carrying header information in which the first level of the digital data is represented by the fundamental wave of the sine wave and the second level is the sum of the fundamental wave and at least one harmonic. The sinusoidal wave generator 63 generates a sinusoidal wave. The header information extracting unit 64 extracts the header information by multiplying the wobble signal read by the reading unit 61 by the sinusoidal wave generated by the sinusoidal wave generating unit 63.

FIG. 17 is an embodiment of the header information reproducing apparatus of FIG.

Referring to FIG. 17, the header information reproducing apparatus includes a pickup unit 71, a detection unit 72, a band pass filter 74, a sine wave generator 73, a multiplier 75, a rectifier 76, and a low pass filter. (77). The pickup section 71 reads the optical signal from the optical disk 700, and the detection section 72 detects the wobble signal from the optical signal. The sinusoidal wave generator 73 generates a sinusoidal wave using a signal output from a phase locked loop (PLL) (not shown) for generating an auxiliary clock signal from the wobble signal. Alternatively, the sinusoidal wave generator 73 may generate a sinusoidal wave separately from the wobble signal detected by the detector 72 to generate a sinusoidal wave and output the synchronous signal to the auxiliary clock signal generated based on the wobble signal. have. That is, the period of the sine wave generated from the sinusoidal wave generator 73 should be equal to that of the wobble signal. Since the signal output from the detector 72 contains a lot of noise, the band pass filter (BPF) 74 removes the noise to improve the detection performance. The multiplier 75 multiplies the detected wobble signal by the sinusoidal wave generated from the sinusoidal wave generator 73. The rectifier 76 rectifies the signal output from the multiplier 75, and the low pass filter (LPF) 77 filters the high frequency signal from the signal output from the rectifier 76 to output the header information.

18 is a waveform diagram of each signal detected from the playback device of FIG.

Referring to FIG. 18, (a) is a signal output from the detector 72, (b) is a signal b output from the bandpass filter 74, and (c) is output from the multiplier 75. Signal, (d) is a signal output from the rectifier 76, (e) represents a signal output from the low-pass filter 77. The horizontal axis of the graph represents frequency and the vertical axis represents amplitude.

Since a lot of noise is included in (a), it is preferable to remove the noise using the band pass filter 74. The low range of the band pass filter 72 goes down to the vicinity of the servo control band. The servo control band means a signal band for controlling the pickup unit 71 to read the wobble signal or to record or reproduce the user data. Therefore, it is preferable to use a high order high pass filter in the low range of the band pass filter 72. Furthermore, it is advantageous in terms of signal detection to use a low order low pass filter in the high range. It is not preferable to use a high order low pass filter in the high range because of the differential effect. The order of the filter is determined by the slope of the attenuation curve represented by the filter.

The signal passing through the band pass filter 74 from (b) can be seen that the noise is removed compared to (a). Multiplying (b) by the sine wave yields a signal like (c). The sinusoids must be multiplied in synchronization for signal detection. The dark portion of (c) represents a synthesized wave generated by adding the sine wave fundamental wave and the third harmonic wave among the wobble signals, and the light portion represents the fundamental wave. (d) is obtained by rectifying (c). When (d) passes through the low pass filter 77, a signal capable of detecting header information is obtained as shown in (e).

19 is a flowchart for explaining a header information reproducing method according to the present invention.

Referring to FIG. 19, the reading unit 61 reads a wobble signal from the optical disc 600. The sinusoidal wave generator 63 generates a sinusoidal wave (step 1901). The header information extractor 64 extracts the header information by multiplying the wobble signal read out from the reader 61 by the sinusoidal wave generated from the sinusoidal wave generator 63 (step 1902).

20 is a flowchart for describing a method for extracting header information according to an embodiment of the present invention. Referring to FIG. 20, the pickup section 71 of the playback apparatus reads out an optical signal from the optical disk 700, and the detection section 72 signals the optical signal read out by the pickup section 71 to generate a wobble signal. (Step 2001). According to the present embodiment, the sinusoidal wave generator 73 generates a PLL pass signal obtained by passing a wobble signal read out from the detector 72 through a PLL (not shown) (step 2002). The playback apparatus extracts the header information by multiplying the wobble signal output from the band pass filter 74 by the PLL pass signal generated from the sine wave generator 73 (step 2003). More specifically, when the WLL signal is multiplied by the PLL passing signal through the multiplier 75 and then rectified by the rectifier 76 and filtered through the low pass filter 77, the header information can be extracted.

The sinusoidal wave generator 73 generates a sinusoidal wave through a separate sinusoidal wave generator (not shown), and then outputs a sinusoidal wave in synchronization with the auxiliary clock signal outputted through the PLL (not shown). Can be.

As described above, the present invention provides an information recording medium capable of recording more user data, a wobble signal recording method, a recording device, a wobble signal reproducing method, and a reproducing apparatus. Further, header information can be extracted and a more stable clock signal can be obtained.

Claims (26)

A track for recording user data; And The first level of data is formed of a sine wave fundamental wave, and the second level includes a first header information formed of a synthesized wave plus the fundamental wave and at least one harmonic, and includes a wobble signal recorded in the track. Information recording medium. The method of claim 1, And the harmonics are second n + 1 harmonics of the sinusoidal wave (n is a positive integer). A track in which user data is recorded; And Information formed on the track, wherein the first level of the digital data is represented by a fundamental wave of a sine wave and the second level comprises a wobble signal containing first header information represented by a combined wave of the fundamental and third harmonics; Record carrier. The method according to any one of claims 1 to 3, And the difference X between the magnitude A of the spectrum of the fundamental wave and the magnitude B of the spectrum of the synthesized wave is less than 30 dB. The method according to any one of claims 1 to 3, And the wobble signal is a single frequency signal. The method of claim 5, And at least a portion of the section in which the first header information is loaded, the second header information being phase-modulated. The method of claim 5, And at least a portion of the section in which the first header information is loaded, the second header information being amplitude modulated. The method according to any one of claims 1 to 3, And the header information includes addressing information. An apparatus for recording a wobble signal on an information recording medium, A wobble signal generation unit configured to generate a wobble signal including first header information represented by a synthesized wave in which a first level of the digital data is represented by a fundamental wave of a sine wave and a second level of the fundamental wave and at least one harmonic; And And a recording unit for recording the wobble signal generated by the wobble signal generating unit on the information recording medium. The method of claim 9, The wobble signal generator A sine wave generator for generating sinusoids and harmonics of the sinusoids; A fundamental wave of the generated sinusoidal wave and an edge-modulator for generating a synthesized wave by combining the fundamental wave and at least one second n + 1 harmonic and modulating header information by using the generated fundamental wave and the synthesized wave. Recording device (n is a positive integer). The method of claim 9 or 10, And the edge-modulation unit modulates the header information into an analog signal by corresponding the fundamental and synthesized waves to first and second levels of digital data, respectively. The method of claim 9 or 10, And the header information includes addressing information. An apparatus for recording a wobble signal on an information recording medium, The first level of digital data is represented by a fundamental wave of a sine wave, and the second level is a single frequency wobble signal containing first header information represented by the sum of the fundamental wave and at least one harmonic, and phase modulated second header information. A wobble signal generation unit generating a; And And a recording unit for recording the wobble signal generated by the wobble signal generating unit on the information recording medium. The method of claim 13, The wobble signal generator A sine wave generator for generating the fundamental and synthesized waves; An edge-modulator for edge-modulating the first header information using the fundamental and synthesized waves; A phase-modulator for phase-modulating the second header information using the fundamental or synthesized waves; And And a signal synthesizing unit for synthesizing the edge-modulation signal output from the edge-modulation unit and the phase-modulation signal output from the phase-modulation unit and outputting the single frequency wobble signal. A method of recording a wobble signal on an information recording medium, (a) generating a fundamental wave of a sinusoidal wave and generating a synthesized wave by adding the fundamental wave and at least one harmonic of the sinusoidal wave; (b) generating a single frequency wobble signal containing edge-modulated header information using the fundamental wave and the synthesized wave; And (c) recording the generated single frequency wobble signal. The method of claim 15, Step (a) is (a1) generating the synthesized wave by adding the fundamental wave and at least one second n + 1 harmonic of the fundamental wave; And and (b2) edge-modulating the header information using the fundamental wave and the synthesized wave (n is a positive integer). The method of claim 16, And (b2) is a step of modulating the fundamental wave and the synthesized wave into analog signals by respectively corresponding the first level and the second level of digital data. A method of recording a wobble signal on an information recording medium, generating a synthesized wave obtained by synthesizing a fundamental wave of a sine wave and at least one harmonic of the fundamental wave and the sine wave; (b) generating a single frequency wobble signal including edge-modulated first header information and phase-modulated second header information using the generated fundamental and synthesized waves; And (c) recording the generated single frequency wobble signal. The method of claim 18 In step (b), (b1) generating an edge-modulated signal by modulating the first header information by mapping the fundamental wave and the synthesized wave to a first level and a second level of digital data, respectively; (b2) phase-modulating the second header information; And and (b3) synthesizing the single frequency wobble signal by superimposing the edge-modulated signal and the phase-modulated signal. A method of reproducing header information from a wobble signal recorded on an information recording medium, (a) reading a wobble signal of a single frequency on which a first level of digital data is represented by a fundamental wave of a sine wave and a second level is represented by a sum of the fundamental wave and at least one harmonic; And and (b) extracting the header information by multiplying the read wobble signal by a predetermined sine wave. The method of claim 20, Step (b) is And extracting the header information by multiplying the wobble signal by passing the wobble signal through a PLL (Phased Locked Loop). The method of claim 21, Step (b) is (b21) generating a clock signal based on the wobble signal; (b22) generating a sine wave and outputting it in synchronization with the clock signal; And (b23) reproducing the header information by multiplying the output sinusoid by the wobble signal. An apparatus for reproducing header information from a wobble signal recorded on an information recording medium, A detector configured to detect a wobble signal having a single frequency on which a first level of digital data is represented by a fundamental wave of a first sinusoidal wave and a second level includes header information represented by a sum of the fundamental wave and at least one harmonic; A sinusoidal wave generator generating a second sinusoidal wave; And And a header information extracting unit for extracting the header information by multiplying the wobble signal detected by the detecting unit by the second sinusoidal wave generated by the sinusoidal wave generating unit. The method of claim 23, wherein The header information extracting unit A multiplier that multiplies the detected wobble signal by the second sinusoidal wave; A rectifier for rectifying the signal output from the multiplier; And a low pass filter (LPF) for filtering the signal output from the rectifier to output a signal in which the header information is represented as digital data. The method of claim 24, And a band pass filter (BPF) for removing noise from the signal output from the detector and outputting the noise to the multiplier. The method of claim 25, And an order of a band of the band pass filter is higher than an order of the low pass filter.