JPS61248269A - Method for transmitting digital signal and its processor - Google Patents

Abstract

PURPOSE:To improve the reliability of a transmission signal between recording and reproducing devices for a digital signal at the transmission of the signal by transmitting the output of a reproducing signal processing means through a recording signal processing means in an equipment on a transmitting side, and receiving the transmitted signal by a recording signal processing means through a reproducing signal processing means in the equipment on a receiving side. CONSTITUTION:Digital data 6a detected and corrected by a reproducing signal processing circuit 11a are inputted to a recording signal processing circuit 12a to add an additional signal such as an error correcting parity and a synchronizing pattern to the input signal 6a and the added signal is outputted to a reproducing signal processing circuit 11b on the recording side. The circuit 11b detects and corrects an error generated in a transmission line A at the time of transmission from a digital VTR 10a to a VTR 10b and outputs the corrected signal to a recording signal processing circuit 12b as an original digital signal 7b. The circuit 12b adds an additional signal such as an error correcting parity and a synchronizing pattern to the digital signal 7b sent from the circuit 11b and outputs the added signal to a magnetic recording/reproducing device 13b. The device 13 records a signal 8b outputted from the circuit 12b in a recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for transmitting digital signals between devices that record and reproduce 8A//i digital signals, and a processing device therefor.

[Background of the invention]

In recent years, the development of equipment for recording and reproducing digital signals has been remarkable, and even for analog signals, analog-to-digital conversion (
There are an increasing number of devices that perform recording and playback using analog-to-digital conversion (A/D conversion).

In such devices, the effects of code errors that occur during recording and reproduction are prevented by recording and reproducing digital signals using error correction codes and the like.

However, when transmitting digital signals reproduced by a device that records and reproduces digital signals to other devices, the number of cables in the transmission path, time errors between devices, or disturbances (instantaneous power outages)
In order to prevent code errors, a separate digital signal processing circuit must be installed between the devices (for example, Japanese Patent Application Laid-open No. 120213/1982), and the scale of the device is reduced. This is a problem in terms of economic efficiency.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a digital transmission method and a processing device thereof that do not impair the reliability of transmitted signals during signal transmission between devices that record and reproduce digital signals.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. In this embodiment, digital VTRs 10a and 10b are used as devices for recording and reproducing digital signals.

First, the configuration of the digital VTR 10a will be explained.

The digital signal 3a after A/D conversion taken into the input terminal 1a is output to the recording signal processing circuit 12a. The recording signal processing circuit 12a adds additional signals such as correction parity and synchronization pattern to the digital data 3a from the input terminal 1a, and outputs the added signals to the magnetic recording/reproducing device 13a. The magnetic recording/reproducing device 13a records the signal 4a output from the recording signal processing circuit 12a on a recording medium such as a magnetic tape, reproduces the ratio signal recorded on the recording medium, and transmits the reproduced signal 5a to the reproduced signal processing circuit 11a. Output as . The reproduction signal processing circuit 11a detects and corrects the next error that occurs during recording and reproduction of the magnetic recording and reproduction device 13a based on error correction parity, etc., and outputs it as the original digital signal 5a to the output terminal 2.
Output to a. Digital hVTR10a and digital fihVT
It has the same configuration as R10b.

Next, the case of transmitting a digital signal from the digital VTR 10a to the digital VTR 10b, which is the transmission method of the present invention, will be explained. The digital VTR 10a is on the reproduction side, and the digital VTR 10b is on the recording side. The digital data 6a detected and corrected by the reproduction signal processing circuit 111 is input to the recording signal processing circuit 12a. The recording signal processing circuit 12□ receives input digital signals 5aVc, V
Additional signals such as error correction parity and synchronization pattern similar to those output to the B recording/reproduction device 13a are added, and the signal is output to the reproduction signal processing circuit 11b on the recording side. The reproduced signal processing circuit 11b receives the digital V from the digital signal box 10a.
The next error that occurs in the transmission path during transmission of the TR, 10b is detected and corrected based on error correction parity, etc., and output as the original digital signal 7b to the recording signal processing circuit 12b. The recording signal processing circuit 12b adds additional signals such as error correction parity and synchronization pattern to the digital signal 7b from the reproduction signal processing circuit 11b, as in the case of the digital signal 3b from the input terminal 1b, and performs magnetic recording and reproduction. Output to device 13b. The magnetic recording/reproducing device 13b performs recording signal processing @4t
The signal 8b output from zb is recorded on a recording medium. With the above operations, the signal transmission from the digital fihVTR, 10a to the digital vTBlOb is completed. According to this embodiment, errors that occur during transmission using the digital transmission method can be effectively prevented, and the reliability of the transmitted signal can be greatly improved.

FIG. 2 shows a recording signal processing circuit 12a of the recording side VT box 10a.
A detailed block diagram is shown.

The recording signal processing circuit 12a includes a changeover switch 121, a parity calculation circuit 122, and a synchronization pattern addition circuit 123).
configured. In the selector switch 121, the input terminal 1a is normally
When transmitting the signal 3a from the reproducing signal processing circuit 11a
The parity calculation circuit 1 selects the digital signal 6a from the
Output to 22.

This parity calculation circuit 122 calculates parity for detecting and correcting errors that occur on magnetic tape, etc.
It is added to the original digital signal 6a.

Next, the synchronization pattern adding circuit 123 adds identification data (synchronization pattern) for word synchronization, and then outputs a signal to the magnetic recording/reproducing device 13a or the recording side VTR 10b.

Next, FIG. 3 shows a detailed block diagram of the reproduction signal processing circuit 11b of the reproduction side VTR 10b. Reproduction signal processing circuit 11
a is a changeover switch 111 to a synchronization pattern detector 112;
It is composed of an error correction circuit 113 and a data restoration circuit 114. The changeover switch 111 switches between the signal 9b from the magnetic tape 13b and the transmission signal from the other reproduction side VTR 10a, and outputs the signal to the synchronization pattern detection circuit 112. The synchronization pattern detection circuit 112 detects a synchronization pattern in the reproduced or transmitted signal to achieve word synchronization, corrects the time axis fluctuation of the signal, and outputs the corrected signal to the correction circuit 113. Next, the error correction circuit 113 detects and corrects winter errors that occur during the recording/reproducing process or during transmission. Finally, the data restoration circuit 114 removes the synchronization pattern, error correction parity, etc., restores the original digital signal, and outputs it to the output terminal 2b and the recording signal processing circuit 12b.

In this embodiment, when transmitting a signal, parity is added to the signal as follows. The data after being reproduced from the magnetic tape and corrected is not directly transmitted as dubbing data, but is first passed through the parity calculation circuit 122 and synchronization pattern addition circuit 123 of the recording signal processing circuit 12a. . This allows the signal to be transmitted as a signal having Scherrer correction capability. In such devices, data is usually processed in bytes, and the data to be transmitted can be connected using nine signal lines, for example, data lines for each byte and a clock line. If the data is transmitted using a signal in the same format as the signal to be recorded (one or two channels of serial data), the data can be transmitted at high speed, but there is an advantage that only a few connection cables are needed between the devices.

The data with parity added in this way is sent to the recording side VTR.
The signal is input to the reproducing circuit, where it is subjected to synchronization detection, time axis correction, and error correction. That is, the reliability of transmitted data can be improved by adjusting the time axis between dubbing devices and correcting errors caused by momentary power outages.

FIG. 4 shows an example of a digital VTR 10a having input/output terminals necessary for implementing the present invention.

This device has at least two input terminals la.

20, and two output terminals 28,30.

12a is a recording signal processing circuit, 13a is a magnetic recording/reproducing device, and lla is a reproduction signal processing circuit.

A normal digital signal is input to the input terminal 1a, while a dubbing digital signal to which high IJT is added is input to the input terminal 20. Further, a normal digital signal is outputted from the output terminal 2a, and a digital signal for dubbing is outputted from the output terminal 30.

Although this embodiment shows an example of a digital VTR,
Needless to say, the present invention can be applied to general digital equipment such as digital audio tapes and optical discs.

〔Effect of the invention〕

According to the present invention, it is possible to significantly improve the reliability of transmission signals during signal transmission between devices that record and reproduce digital signals.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present method invention, FIG. 2 is a diagram for explaining the recording signal processing means of FIG. 1, and FIG.
FIG. 4 is a diagram for explaining the reproduced signal processing means shown in FIG. 4, and is a diagram showing an embodiment of the present invention. M2 Eye 3rd figure

Claims (1)

[Claims] 1. Recording signal processing means for adding an additional signal to a digital signal; recording and reproducing means for recording and reproducing the output signal of the recording signal processing means; detecting and correcting errors contained in the reproduced signal of the recording and reproducing means; A method of transmitting a digital signal between two or more devices comprising a reproduced signal processing means for reproducing a digital signal, the transmitting side device transmits the output of the reproduced signal processing means via the recorded signal processing means, and receives the output of the reproduced signal processing means. A digital signal transmission method 2, characterized in that the side device receives a transmitted signal by the recording signal processing means via the reproduction signal processing means, a recording signal processing means for adding an additional signal to the digital signal, and the recording signal processing means A digital signal processing device comprising a recording and reproducing means for recording and reproducing an output signal of the signal processing means, and a reproducing signal processing means for detecting and correcting errors contained in the reproduced signal of the recording and reproducing means and reproducing the original digital signal. wherein the recording signal processing means and the reproduction signal processing means each have two or more input terminals and output terminals, and switching means for switching the input terminals and the output terminals,
A digital signal processing device, characterized in that the output terminal of the reproduction signal processing means and the input terminal of the recording signal processing means are connected by the switching means.