JP2001126264A - Inter-code interference analyzer and recording medium recording inter-code interference analytic program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an inter-code interference analyzer visually and intuitively judging an interference result and efficiently performing analysis and a recording medium recording an inter-code interference analytic program. SOLUTION: This device improves the inter-code interference analyzer analyzing an inter-code interference by the code length data of a code signal of an optical disk. This device is provided with a code length data storage part storing the code length data, an extraction means extracting continuous two code length data from the code length data of the code length data storage part as a set of the front data, the rear data, an extracted data storage part holding the data extracted by the extraction means and a display means line-displaying the ideal code lengths of the front data, the rear data and plot-displaying the data of the extracted data storage part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intersymbol interference analyzer and an intersymbol interference analyzer for analyzing intersymbol interference of code length data of a code signal of an optical disc, for example, a CD-R, CD-RW, DVD-RAM or the like. The present invention relates to an inter-symbol interference analysis device capable of efficiently analyzing a recording medium on which an analysis program is recorded, and a recording medium on which an inter-symbol interference analysis program is recorded.

[0002]

2. Description of the Related Art With the development of multimedia in recent years, data such as images, sounds, and moving images can be freely handled, but the file size increases, and more data can be stored and edited more quickly. It is becoming important. Along with this, the market for data rewritable optical disks, for example, CD-R, CD-RW, DVD-RAM, etc. has expanded, and the development of large-capacity, high-speed transfer rate writing drives and writable media has rapidly progressed. In. In this development, optimization of data writing control and the like are performed by analyzing a writing code length deviation.
An apparatus for performing such an analysis is shown in FIG. 9 and described.

In FIG. 1, a code length data storage unit 11 stores
It holds the code length data of the code signal of the optical disk. In the case of DVD, the code length data is the code length of 10 types of pulse width modulation (Eight-to-Fourteen Modulation), that is,
It is pulse width measurement data of 3T to 11T and 14T (T: cycle of sampling clock).

[0004] The operation unit 12 is composed of, for example, a switch. The extraction condition storage unit 13 holds extraction conditions. The extraction condition setting means 14 extracts an extraction condition to be extracted from the code length data storage unit 11 by the input of the operation unit 12.
Set to 3.

[0005] The extraction means 15 extracts the corresponding data from the contents of the code length data storage unit 11 and the extraction condition storage unit 13 in accordance with an instruction from the operation unit 12. Extracted data storage unit 1
Reference numeral 6 holds the extracted data extracted by the extraction means 15.

The statistical calculation means 17 calculates a statistical value (average value, jitter value, etc.) based on the code length data of the code length data storage section 11 or the extracted data of the extracted data storage section 16 and classifies the code length. Create a histogram for each. The statistic storage unit 18 holds the statistic of the statistic calculation unit 17. The histogram storage unit 19 holds the histogram of the statistical operation unit 17.

[0007] The display means 20 displays the statistical value of the statistical value storage unit 18 and the histogram of the histogram storage unit 19 on a display screen. Further, the display means 20 displays the extraction conditions input by the operation unit 12 on a display screen. Display 2
Reference numeral 1 denotes a CRT, a liquid crystal monitor, or the like, which displays a display screen.

The extraction condition setting means 14, the extraction means 15, the statistical calculation means 17, and the display means 20
0.

Next, a display screen displayed on the display unit 21 will be described with reference to FIG. In the figure, the display screen 30
An extraction condition display section 31, an analysis start button 32, a statistics display section 33, an extraction statistics display section 34, a histogram display section 35,
It consists of an extraction histogram display section 36.

The operation of such an apparatus will be described below with reference to FIGS. FIG. 11 is a flowchart showing the operation of the device shown in FIG. 9, and FIG. 12 is a diagram for explaining the operation of the device shown in FIG.

The input of the operation unit 12 causes the display means 20
Displays the extraction condition on the extraction condition display unit 31. At the same time, the extraction condition setting means 14 stores the extraction conditions in the extraction condition storage unit 13 (S1). Here, the extraction condition is such that a 3T mark (a portion where data has been written) is a trigger, and a target (analysis target) is a space (a portion where no data has been written) after the trigger code length.

Then, when the analysis start button 32 is pressed by the operation unit 12, the extraction means 15 extracts the relevant data from the contents of the code length data storage unit 11 and the extraction condition storage unit 13, and extracts the data. (S2). Therefore, since the data is after the 3T code length, as shown in FIG. 12, 7T, 6T, 10T, 3T.
It is stored in the extracted data storage unit 16.

The statistical operation means 17 classifies the code length data of the code length data storage unit 11 or the extracted data of the extracted data storage unit 16 for each code length, and generates a statistical value (average value, jitter value, number of corresponding data number). ) Is calculated and stored in the statistical value storage unit 18. As a result, the statistical values of the extracted data have the contents shown in FIG. In addition, the statistical operation unit 17 creates a histogram for each code length classification based on the code length data of the code length data storage unit 11 or the extracted data of the extracted data storage unit 16, and stores the histogram in the histogram storage unit 19 (S3). ).

Then, the display means 20 displays the statistical value storage unit 1
The statistical value from the code length data storage unit 11 is displayed on the statistical display unit 33, and the statistical value from the extracted data storage unit 16 of the statistical value storage unit 18 is displayed on the extracted statistical display unit.
The display means 20 displays the histogram from the code length data storage unit 11 of the histogram storage unit 19 on the histogram display unit 35, and displays the histogram from the extracted data storage unit 16 of the histogram storage unit 19 on the extracted histogram display unit 36. (S4).

[0015]

In such a device,
It is possible to analyze the interference to the adjacent code by one trigger. However, extraction conditions had to be changed many times in order to perform interference analysis between adjacent codes in all combinations. In addition, even if the extraction conditions are changed and the interference relations are analyzed in all combinations, the results of the statistical values and the histograms are independent of each other, so that the interference relations of all code length data can be visually and intuitively determined. could not.

An object of the present invention is to provide an intersymbol interference analysis apparatus and a recording medium storing an intersymbol interference analysis program capable of visually and intuitively judging interference results and efficiently analyzing the results. Is to do.

[0017]

According to the present invention, there is provided an intersymbol interference analyzer for analyzing intersymbol interference based on the code length data of a code signal of an optical disk, a code length data storage unit for storing the code length data, Extracting means for extracting two consecutive code length data from the code length data in the code length data storage unit as a set of preceding data and subsequent data;
An extracted data storage unit that holds the data extracted by the extracting means, and the preceding data, the ideal code length of the subsequent data is displayed as a line, and the data of the extracted data storage unit is
Display means for displaying a plot is provided.

Also, in a recording medium for recording an intersymbol interference analysis program for analyzing intersymbol interference based on the code length data of a code signal of an optical disk, two consecutive code length data are converted from the code length data to a previous data. , Extracted as a set of post-data, the ideal code length of the pre-data and post-data is displayed as a line, and the extracted data is plotted and displayed.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing one embodiment of the present invention. In the figure, a code length data storage unit 41 stores code length data of a code signal of an optical disk. The operation unit 42 includes, for example, a switch. The extraction condition storage unit 43 holds the extraction condition. Extraction condition setting means 44
Are input to the code length data storage 41
Are set in the extraction storage unit 43.

In accordance with an instruction from the operation unit 42, the extraction unit 45 extracts two consecutive code length data from the contents of the code length data storage unit 41 and the extraction condition storage unit 43,
A set of the two-dimensional array of the subsequent data is classified and extracted according to the code length. The extraction data storage unit 46 includes an extraction unit 45
The data extracted in is stored in a matrix.

The deviation calculating means 47 calculates an average by calculating an average value for each classification of the preceding data and the subsequent data in the extracted data storage unit 46. Deviation is the deviation from the ideal value, that is, (ideal value)-
(Average value). Deviation storage unit 48
Holds the deviation of the deviation calculation means 47 in a matrix.

The display means 49 displays the ideal code lengths of the preceding data and the succeeding data in a dashed line, and also plots and displays the data of the extracted data storage unit 46 two-dimensionally on a display screen. The display means 49 displays the deviation of the deviation storage unit 48 in a plot display or a linear interpolation display on a display screen. Then, the display unit 49 displays the operation unit 4
2 displays the extraction conditions input on the display screen. The display unit 50 displays a display screen on a CRT, a liquid crystal display, or the like.

The extraction condition setting means 44, the extraction means 45, the deviation calculation means 47, and the display means 49
The control unit 200 is configured. Further, extraction condition setting means 4
4. The extraction unit 45, the deviation calculation unit 47, and the display unit 49 are generally created by a program, and the program is recorded on a recording medium such as an FD or a CD-ROM. Then, the program is installed in the computer from the recording medium, and configures the intersymbol interference analyzer.

Next, a display screen displayed on the display unit 50 will be described with reference to FIG. In the figure, a display screen 60 includes an extraction condition display section 61, an analysis start button 62, and a matrix display section 63.

The operation of such an apparatus will be described below with reference to FIGS. FIG. 3 is a flowchart showing the operation of the apparatus shown in FIG. 1, FIGS. 4 and 5 are diagrams for explaining the operation of the apparatus shown in FIG. 1, and FIGS. 6 to 8 are examples of display screens of the apparatus shown in FIG.

In response to an input from the operation unit 42, display means 49
Displays the extraction condition on the extraction condition display section 61. At the same time, the extraction condition setting unit 44 stores the extraction condition in the extraction condition storage unit 43 (S1). Here, as the extraction condition, all code lengths are set as triggers, and the target is set as code length data after the trigger code length.

When the analysis start button 62 is pressed by the input of the operation unit 42, the extraction unit 45 extracts the relevant data from the contents of the code length data storage unit 41 and the extraction condition storage unit 43, and stores the extracted data. Stored in the section 46 (S
2). Therefore, since the data is after the entire code length, (3T, 7T), (11T, 4T),
(3T, 6T)... Are extracted. Since the data is arranged alternately like a mark, a space, a mark, etc., when a mark is used as a trigger, a set of (space, mark) is used, and when a space is used as a trigger, (mark, space) is used.
Is extracted as a set. At this time, the cells of the matrix
The values of the previous data and the subsequent data of all the corresponding data, the total number of data of the cells, and frequency information of the same set are stored. Then, using the preceding data as the Y axis and the following data as the X axis, the data is arranged and grouped for each code length.

Then, the deviation calculating means 47
An average value for each classification of the pre-data and post-data of the extracted data storage unit 46 is obtained, and a deviation value (deviation) of the code length data from the ideal value is calculated based on the average value, and stored in the deviation storage unit 48 as shown in FIG. (S4).

The display means 49 displays the ideal code length as a broken line, reads the data from the extracted data storage section 46, and plots the data on the matrix display section 63 with the previous data as the Y axis and the subsequent data as the X axis. Are displayed as shown in FIGS. 2 and 6 (S5). Here, FIG. 6 is an enlarged view of a part of the matrix display section 63 shown in FIG. Ideally, the code length is at the intersection of the XY code lengths. However, there is interference between adjacent codes. For example, when the preceding data is 3T and the following data is 6T, the code length is particularly shifted. It is visually and intuitively obvious that it is large.

At this time, the display means 49 can use the frequency information of the extracted data storage unit 46 to perform color display by color and display gradation. As a result, the information in the three-dimensional direction is added to the two-dimensional distribution information, and the analysis can be further assisted.

The display means 49 reads the deviation value from the deviation storage section 48 and displays the deviation value of the previous data on the Y-axis in the matrix display section 63.
The deviation value of the subsequent data is plotted on the X axis and displayed as shown in FIG. 7 (S5). With this display, the deviation for each code length can be visually and intuitively grasped as the distance from the intersection. Note that the deviation plot shown in FIG. 7 is a point located approximately at the center of the extracted plots of the preceding data and the subsequent data.

Then, the display means 49 linearly interpolates each deviation value of the two-dimensional cell of the deviation storage section 48 for each of the preceding data and the following data, and as shown in FIG.
It is displayed on the matrix display section 63 (S5). In this example, the deviation value in the X direction (post data) is plotted in the Y direction, and the deviation value in the Y direction (previous data) is plotted as X
It plots in the direction and performs linear interpolation. By doing so, the deviation of all post-data of a certain code length can be regarded as a deviation from the X-axis, and the deviation of all pre-data of a certain code length can be regarded as a deviation from the Y-axis. In this analysis, it is ideal that the axes of the respective code lengths coincide with the broken lines of the matrix display section 63. However, it is possible to visually determine qualitative quality based on the degree of lattice distortion.

In this embodiment, the extraction conditions are all data. However, it is also possible to perform inter-code interference analysis of adjacent data after a certain code length and before a certain code length.

The X-axis and the Y-axis of the preceding data and the succeeding data may be any one, and the ideal code length line may be a solid line instead of a broken line.

Then, the structure in which the extracting means 45 performs classification by the code length and stores it in the extracted data storage unit 46 has been described. However, the extraction unit 45 may store the data in the extracted data storage unit 46 without performing classification. In this case, the deviation calculation means 47 reads the extracted data from the extracted data storage unit 46 by classification based on the code length, calculates the average value, and calculates the deviation.

[0036]

According to the present invention, the following effects can be obtained. According to the first aspect, the extracting means sets two consecutive code length data from the code length data in the code length data storage unit as a set of front data and rear data, and the display means displays the set as front data, The post-data is putt-displayed as a vertical axis and a horizontal axis. Therefore, the interference result can be visually and intuitively determined, and the analysis can be efficiently performed.

According to the second aspect, the display means displays the gradation of the plot according to the frequency of the data in the extracted data storage unit, so that the information in the three-dimensional direction is added and the analysis can be further assisted.

According to the third aspect, the deviation calculating means calculates an average value for each classification of the pre-data and post-data in the extracted data storage unit, and calculates a deviation of the code length data from the ideal value based on the average value. Then, the deviation is plotted and displayed by the display means. Thereby, the distance from the intersection for each code length can be grasped visually and intuitively, and the analysis can be performed efficiently.

According to the fourth aspect, the deviation calculating means obtains an average value for each classification of the preceding data and the following data in the code length data storage unit, and calculates the deviation of the code length data from the ideal value based on the average value. The deviation point is calculated and displayed by the display means by linear interpolation. This makes it possible to visually determine qualitative quality based on the degree of lattice distortion.

According to the fifth aspect, two consecutive code length data from the code length data are set as a set of the front data and the rear data, and this set is defined as the front data and the rear data as the vertical axis and the horizontal axis. Putt display. Therefore, the interference result can be visually and intuitively determined, and the analysis can be efficiently performed.

According to the sixth aspect, the plot is displayed in gradation according to the frequency of the preceding data and the subsequent data.
The information in the three-dimensional direction is added, which can further assist the analysis.

According to the seventh aspect, the average value of the preceding data and the subsequent data is obtained for each classification, and the deviation of the code length data from the ideal value is calculated based on the average value, and the deviation is plotted and displayed. Thereby, the distance from the intersection for each code length can be grasped visually and intuitively, and the analysis can be performed efficiently.

According to the eighth aspect, an average value for each classification of the preceding data and the following data is obtained, a deviation from the ideal value of the code length data is calculated based on the average value, and the deviation point is linearly interpolated. indicate. This makes it possible to visually determine qualitative quality based on the degree of lattice distortion.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing a display screen of the device shown in FIG.

FIG. 3 is a flowchart showing an operation of the apparatus shown in FIG.

FIG. 4 is a diagram illustrating the operation of the device shown in FIG.

FIG. 5 is a diagram for explaining the operation of the device shown in FIG. 1;

FIG. 6 is a diagram showing a display screen of the device shown in FIG.

FIG. 7 is a diagram showing a display screen of the device shown in FIG.

8 is a diagram showing a display screen of the device shown in FIG.

FIG. 9 is a diagram showing a configuration of a conventional intersymbol interference analyzer.

FIG. 10 is a diagram showing a display screen of the device shown in FIG.

11 is a flowchart showing the operation of the device shown in FIG.

FIG. 12 is a view for explaining the operation of the device shown in FIG. 9;

[Explanation of symbols]

 41 Code length data storage unit 45 Extraction unit 46 Extracted data storage unit 47 Deviation calculation unit 48 Deviation storage unit 49 Display unit

Claims (8)

[Claims] 1. An intersymbol interference analyzer for analyzing intersymbol interference based on code length data of a code signal of an optical disk, comprising: a code length data storage unit for storing the code length data; Extracting means for extracting two consecutive code length data from the long data as a set of previous data and subsequent data; an extracted data storage unit for holding the data extracted by the extracting means; An intersymbol interference analysis apparatus, further comprising a display unit that displays an ideal code length in a line and plots and displays data of the extracted data storage unit. 2. The intersymbol interference analyzer according to claim 1, wherein the display means performs gradation display based on the frequency of the data in the extracted data storage unit. 3. A deviation calculating means for calculating an average value of the preceding data and the following data of the extracted data storage unit for each classification by code length, and calculating a deviation of the code length data from an ideal value based on the average value. 3. The inter-symbol interference analysis according to claim 1, further comprising a deviation storage unit for storing the deviation of the deviation calculation unit, wherein the display unit plots and displays a deviation point based on the deviation of the deviation storage unit. apparatus. 4. A deviation calculating means for calculating an average value of the preceding data and the following data of the extracted data storage unit for each classification by code length, and calculating a deviation of the code length data from an ideal value based on the average value. 3. A deviation storage unit for storing a deviation of the deviation calculation unit, wherein the display unit linearly interpolates and displays a deviation point for each deviation of the deviation storage unit. Interference analyzer. 5. A recording medium for recording an intersymbol interference analysis program for analyzing intersymbol interference based on the code length data of a code signal of an optical disk, comprising: A recording medium on which an intersymbol interference analysis program is extracted, which is extracted as a set of post-data, and the ideal code lengths of the pre-data and post-data are displayed in a line, and the extracted data is plotted and displayed. 6. The recording medium according to claim 5, wherein the gradation display is performed according to the frequency of the preceding data and the succeeding data. 7. An average value of the preceding data and the following data is obtained for each classification by code length, a deviation from the ideal value of the code length data is calculated based on the average value, and a deviation point is plotted and displayed based on the deviation. A recording medium on which the intersymbol interference analysis program according to claim 5 or 6 is recorded. 8. An average value of the preceding data and the following data is obtained for each classification by code length, a deviation from the ideal value of the code length data is calculated based on the average value, and a deviation point for each deviation is linearly interpolated. A recording medium on which the intersymbol interference analysis program according to claim 5 or 6 is displayed.