JPH02177729A - 1:1 hot standby system communication equipment - Google Patents

Abstract

PURPOSE:To prevent silent failure by providing a means monitoring quality of a transmission line to a receiving end, controlling a switch and applying own station loopback to a line not in use as the line in its own station so as to always monitor the state of a standby equipment. CONSTITUTION:Suppose that active/standby detectors 6A, 6B are normal at a sending end while a transmission output is in fault due to a fault of an active modulation section 3A. Since the sending end cannot detect the fault in this state, a changeover device 8 keeps the active position. Then a monitor circuit 18 of the receiving end recognizes it that the active signal is in error. If the standby signal is in error and the state durates for a long time, a transmission switching request signal is sent to the sending end through an inverse line transmission circuit 13 under the control of the monitor circuit 18. When a circuit subject to own station loopback at the sending end is not in error on the other hand, a control circuit 9 at the sending end controls the switch 8 to select a standby modulation section 3B.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an l:l backup hot standby type communication device, and particularly to a communication device that prevents silent fariers caused by switching from active to standby. Possible l:i% [Related to hot standby communication device.

[Prior Art] FIG. 2 is a block diagram of a conventional l=1 backup hot standby type communication device.

In the figure, 1 is a transmitting side input terminal, 2 is a hybrid,
3A and 3B are modulation sections, 5A and 5B transmission sections, 6A and 6B are detectors that detect the output power of the transmission sections 5A and 5B, 8 is a switch, 10 is an air line, and these are the transmission ends. ing.

In addition, 12 is a hybrid, 14A and 14B are receiving sections,
17A and 17B are demodulators, 19 is a switch, and 20 is an output end, which together constitute a receiving end.

In the above configuration, the switching control at the transmitting end is performed by the transmitting unit 5A.
, 5B is detected by the detectors 6A and 6B, and the switching device 8
is switching.

Further, switching control at the receiving end is performed by the demodulator 17A.

The switch 19 is switched depending on the presence or absence of the alarm 17B.

Therefore, in the 1:1 backup hot standby type communication device having such a configuration, switching control is performed independently at the transmitting end and the receiving end.

[Problems to be Solved] The conventional 1:1 backup hot standby communication device described above cannot completely monitor failures at the transmitting end only at the transmitting end, so when a failure occurs on the transmission path, In some cases, it may not be possible to determine whether the fault is at the transmitting end or the receiving end, and switching is performed independently at the transmitting and receiving ends, resulting in a large amount of time being required to save the line. There was a problem that there was a possibility that the service would be disconnected for a long time.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an l:l standby hot standby type communication device that is capable of linking abnormality detection at the transmitting end and the receiving end to quickly repair the line. shall be.

[Means for Solving the Problems] In order to achieve the above object, the 1=1 standby hot standby type communication device of the present invention includes a transmitting means having a working and a standby transmission path, and switching between the working and standby transmitting means. a transmitting-side switching means; a transmitting-side abnormality detecting means for detecting an abnormality in the transmitting means and outputting switching information to the transmitting-side switching means; a receiving means having a working and a backup receiving path; receiving side switching means for switching the receiving means; receiving side abnormality detection means for detecting an abnormality in the receiving means and outputting switching information to the receiving side switching means; and a backup path between the transmitting means and the receiving means. A local loopback switching connection means that performs local loopback and detects an abnormality by connecting a local loop back, and a local loopback switching connection means that monitors the transmission path quality at the receiving end and requests the transmitting end to switch to the working backup when the transmission path quality deteriorates. A transmission line quality monitoring means for outputting a signal, a reverse line switching signal transmitting/receiving means for communicating a working/standby switching request signal from the receiving end to the transmitting end, and a working/standby switching request signal being communicated from the receiving end to the transmitting end. The configuration includes reverse line switching control means for controlling the transmitting side switching means to switch between active and standby lines in the case where the transmitting side switching means is used.

[Example] Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a block diagram of a [1 backup hot standby type communication device] according to an embodiment of the present invention, with the upper stage being the transmitting side and the lower stage being the receiving side. Note that parts common to or corresponding to those of the conventional example are denoted by the same reference numerals.

In the figure, 4 is a switch circuit, 7 is a reverse line multiplier circuit, 9 is a control circuit for the switch 8 (reverse line switching control circuit), 2
1 is a transmitter/receiver duplexer. Further, 13 is a reverse circuit transmission circuit;
15 and 16 are switch circuits, and 18 is a transmission path quality monitoring circuit that monitors the continuity of transmission signals. It should be noted that the switch circuits 4, 15 and 16 have the same structure, and there are two connection states in the figure: a connection indicated by a solid line and a connection indicated by a broken line.

On the transmitting side having the above configuration, a signal applied to the transmitting side input terminal 1 is branched in two directions by the hybrid 2,
The signal is input to modulators 3A and 3B.

The modulated human input signal is then input to the transmitters 5A and 5B, and further passes through the switch 8 and the duplexer 21 to the antenna l.
Guided by O.

On the other hand, on the receiving side, the signal received by the antenna 10 is input to the hybrid 12 via the duplexer 21, where it is split into two and input to the receiving sections 14A and 14B. Then, the demodulators 17A and 17B are manually operated, and there is also a switch for switching between working and standby! 9 and is output from the output end 20.

Here, one terminal of the switch circuit 4 is terminated, two of the other three terminals are connected to the modulation sections 3A and 3B, and the remaining terminals are connected to the switch circuit 15. Further, the remaining terminals of the switch circuit 15 are connected to the receiving section 1
4A, the demodulator 17A, and the switch circuit 16, one terminal of the switch circuit 16 is terminated, and the other two terminals are connected to the receiver 14B and the demodulator 17B.
It is connected to the. In addition, switch circuit 4゜15.16
If all are solid connections and the lines are normal, then
The transmission switch 8 selects the input/output of the transmitter 5, and the receiver switch 19 selects the demodulator 17A.

Now, even though the active/backup detectors 6A and 6B at the transmitting end are normal and the modulators 3A and 3B are not issuing an alarm, the transmission output becomes abnormal due to a failure in the active modulator 3A. Suppose it became.

In this state, since no abnormality can be detected at the transmitting end, the switch 8 remains on the working side, but at the receiving end, the monitoring circuit 18 recognizes that there is an abnormality in the working signal. If there is no abnormality in the circuit connecting the local station at the receiving end, connect the switch circuit 16 as shown in the broken line, and
Pass the signal to both spares.

However, at this time, there is an abnormality in the preliminary signal, and if this condition continues for a long time, a transmission switching request signal is sent to the transmitting end through the reverse circuit transmitting circuit 13 under the control of the monitoring circuit 18. On the other hand, if there is no abnormality in the circuit looping back to the local station at the transmitting end and a switching request signal is sent from the receiving end, the control circuit 9 at the transmitting end controls the switching device 8 and The device (modulator 3B) is selected.

Through these sequences, the transmission path is restored.

Furthermore, by connecting the switch circuit 4 at the transmitting end as indicated by a broken line, this can be used to investigate the cause of the previous transmission abnormality.

That is, here, the following sequence control is performed.

■Both the transmitting end and the receiving end are working lines, and the backup line is looped back to the local station.

■If an abnormality is detected in the working line at the receiving end and there is no abnormality in the protection line looped back to the local station, the loopback is canceled and the signal is passed to the protection line, and if no abnormality is detected, the A switch is used to switch from active to standby and save the line.

(2) However, if an abnormality is detected in the protection line when the signal is passed through the protection line, a transmission switching request signal is sent from the receiving end to the sending end to control the switching device at the sending end. If no abnormality is detected in the protection line that is looped back to the transmitting end when the switching request signal is received at the transmitting end, the switching device switches from the working line to the standby line and rescues the line.

In other words, the receiving end is equipped with means for monitoring the quality of the transmission path. This information is then used to switch between working and standby at the receiving end.

Additionally, circuits that are not used as lines are self-loopbacked to diagnose device failures.

When it is determined that there is no abnormality at the receiving end based on the diagnosis results and the quality monitoring results of the transmission path, the control information for the switching device at the transmitting end is used to efficiently switch the transmitting end and the receiving end. be able to.

[Effects of the Invention] As explained above, the present invention allows information in which signal continuity is lost to be sent from the receiving end to the transmitting end as a transmission switching request signal to control the switching device, and also to be used as a line at the own station. Since the status of the standby side is constantly monitored by looping back circuits that are not connected to the local station, switching between the transmitting end and receiving end can be done to the minimum necessary, making it possible to prevent silent faeria. Nal:】
This has the effect of providing a backup hot standby type communication device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a 1:1 standby hot standby communication device according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional 1:1 hot standby communication device.
FIG. 1 is a block diagram of a hot standby type communication device. 2, l 2 3A, 3B 4, 15. 16 5A, 5B 6A, 6B 8, l 9 14A, 14B: Hybrid: Modulation section: Switch circuit: Transmission section: Detector: Reverse line multiplier circuit: Switcher 2 control circuit: Antenna: Receiving section: Reverse line transmitting circuit 17A, 17B: Demodulator: Transmission path quality monitoring circuit Figure 1

Claims (1)

[Claims] a transmission means having a working and backup transmission path; a transmission side switching means for switching between the working and backup transmission means; and a transmission means for detecting an abnormality in the transmission means and outputting switching information to the transmission side switching means. a side abnormality detection means, a receiving means having a working and standby receiving path, a receiving side switching means for switching between the working and standby receiving means, and a receiving side switching means that detects an abnormality in the receiving means and detects an abnormality in the receiving side. receiving-side abnormality detection means for outputting switching information; local loopback switching connection means for performing abnormality detection by connecting a backup path in the transmitting means and receiving means to perform local loopback; and transmitting at the receiving end. a transmission path quality monitoring means for monitoring the path quality and outputting a working protection switching request signal to the transmitting end when the transmission path quality deteriorates;
reverse line switching signal transmitting/receiving means for communicating a working/standby switching request signal from the receiving end to the transmitting end; and controlling the transmitting side switching means when the working/standby switching request signal is communicated from the receiving end to the transmitting end. A reverse line switching control means for switching between active and backup lines.1:
1. Spare hot standby communication equipment.