JPS59143434A - Carrying device of cable - Google Patents

Abstract

PURPOSE:To eliminate the need for another pair of cables and to simplify an oscillation circuit by providing a voice direction filter and a voice LPF to a repeater and connecting these parts to a monitoring frequency oscillator. CONSTITUTION:The frequency of a cable is separated into high and low group frequency 12kHz-190kHz and the frequency 0.3kHz-8kHz for an ordering circuit and a repeater monitoring oscillator 6 by the voice direction filter 7. The frequency band of 12-120kHz is inputted to a low and high group direction filter 5 and the frequency band of 0.3-8kHz is inputted to the output side of the repeater monitoring oscillator 6 and a voice LPF8. The input frequency of the order OW is converted into the frequency band of 0.3-2.1kHz by the LPF8 and coupled by the filter 7 and the coupled frequency is sent to a manned station of the opposite terminal station. Since the monitoring and ordering circuits are coupled with the signal transmission band, another pair of cables are not requird and the monitoring frequency can be used within 2.5-4kHz in which line loss is low, so that the oscillation circuit can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to cable transport equipment, and more particularly to a monitoring and coordination circuit for cable transport lines used as short-haul transport multiplex communication lines.

Conventionally, cable conveyance devices have used a group-based two-wire transmission system, and the signal transmission frequency bands for transmission and reception are different. In addition, the repeater has a built-in amplifier for line loss correction and is deployed at sea for about 10 days, installed on a pole, in a manhole, etc., and has a tandem connection configuration. As shown in Fig. 1, the circuit of this relay device uses a directional filter 5 for the low group and high group to separate signal transmission frequencies of 12 to 60 KI (Z) on the low group side and 72 to 120 KI (Z) on the high group side. The line monitoring current of 60KHz (for low group) and 72KH2 (for high group) is transmitted to the trench at the same time, and the line amplifier 1 for low group and high group On the output side of the group line amplifier 2, the line monitoring current is constantly monitored for the presence or absence of a specified level by the low group pilot monitoring circuit 3 and the high group pilot monitoring circuit 4, and its output is monitored by the repeater monitoring oscillator. 6 (oscillation frequency is 12KH2 or less).This oscillator has the function of oscillating when the level is normal and stopping when there is an abnormality.The output is connected to a monitoring line separate from the required cable line, and the relay This monitoring line is also used as a 2W meeting line during maintenance between the terminal station and the relay device, and between the relay devices and the relay device. Visual signal oscillator frequency is 2W
Frequencies excluding the audio frequencies O03 to 4KH2 of the meeting line are used.

The conventional method requires a separate cable in addition to the signal transmission line cable. Furthermore, since the meeting line and cable are shared, there is a drawback that the low frequency of the repeater monitoring oscillator cannot be used.

The present invention provides a circuit that eliminates the drawbacks of the conventional system described above, and includes installing an audio direction filter and an audio low-frequency p-wave filter in a relay device of a cable carrier line, and using these to monitor frequencies. This device is characterized in that it is connected to an oscillator to form a relay device monitoring and negotiation circuit.

An embodiment of the present invention will be described below with reference to FIG.

In FIG. 2, the same components as those in FIG. 1 will be described with the same reference numerals.

In the embodiment, the frequency of the cable line is divided into high group and low group frequencies (12KHz to 12QK
Hz) and the oscillator 60 frequency (0°3KF (Z ~ 8KHz) for monitoring the meeting line and repeater.Then, the frequency band of 12KHz ~ 120IG (z is input to the low group and high group direction P wave generator 5). 0.3KHz~8KH
The frequency band z is input to the output side of the repeater monitoring oscillator 6 (output frequency 3 KHz to 8 KHz) and the audio low-pass p-wave generator 8.

The input frequency of the meeting OW is removed by the audio low frequency F-wave generator 8, which removes the high frequency side (2.1 KHz or more) and converts it into a frequency range of 0.3~
2, IK)Iz, which is synthesized with the output frequency of the repeater monitoring oscillator 6, combined by the audio direction filter 7, and sent to the opposite end station, which is a manned station, via the cable line.

Note that the separation and combination of low group and high group signal frequencies, and the connection and method of the repeater monitoring oscillator are the same as in the prior art.

As explained above, the present invention connects the monitoring and meeting lines, which were conventionally constructed with separately sealed cables, to the signal transmission band, thereby eliminating the need for separately sealed cables. In addition, the frequency for repeater monitoring is 2.5KHz~, which has very low line loss.
4 kHz can be used, and the oscillator circuit can be made simple and inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional example, and FIG. 2 is a block diagram showing an embodiment of the present invention. 1... Line amplifier for low group, 2... Line amplifier for high group, 3... Pilot monitoring circuit for low group, 4... Pilot monitoring circuit for high group, 5... Direction F wave device for low group and high group, 6... Oscillator for repeater monitoring. 7...Audio direction filter, 8...Audio low-frequency P-wave device patent applicant NEC Corporation

Claims (1)

[Claims] (1) A cable conveyance device characterized in that an audio direction filter and an audio low-frequency p-wave filter are installed in a relay device of a cable conveyance line, and these are connected to a frequency oscillator for monitoring.