JPH05260168A - Highway fault switching system - Google Patents

Abstract

PURPOSE:To prevent the whole of a device from being regarded as faulty by switching of only the fault position even in the case of the fault in a partial highway in the telephone exchange provided with plural highways. CONSTITUTION:In the device which has plural intra-device highways 2 for switch part 1, a spare highway 3 is provided, and each highway is divided into plural sections, and a fault detecting circuit 4 is provided for each section. A fault of intra-device highways is detected to output a fault detection signal, and a switching circuit 5 is provided, and the intra-device highway 2 in the fault section is switched to the spare highway 3 by the output of this fault detection signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fault recovery system for a telephone exchange, etc., and more particularly to a highway fault switching system for preventing the entire system from being considered as a fault even if a fault occurs on a part of the highways. It is about.

Generally, in a telephone exchange, a plurality of highways are provided for each switch unit in order to transmit a voice signal exchange-processed in the switch unit.

In such an apparatus having a plurality of highways, it is desired that the entire apparatus should not be regarded as a failure even if a failure occurs in a part of the highways.

[0004]

2. Description of the Related Art FIG. 6 shows a conventional fault in a telephone exchange.
10 is used for explaining the switching method at the time
(ACT) system, 11 and 12 are switch parts, 13_1,
Thirteen_2,… _,Thirteen_nIs a highway. 20 is spare
(SBY) system, 21 and 22 are switch parts, 23_1,
23_2,…_,23_nIs a highway.

Conventionally, in a telephone exchange, when the highway fails, it is common to switch the entire device to the standby system. For example, a failure occurs in the highway 13 ₂ of the ACT system 10 in FIG. If you do,
The entire ACT system 10 is regarded as a failure, and is switched to the SBY system 20.

[0006]

As described above, in the telephone exchange, even if a failure occurs in a part of the highway, the entire apparatus can be regarded as a failure and switched to the standby system. However, as shown in FIG. 6, a telephone exchange is usually provided with a plurality of highways per device. Therefore, the highways other than the faulty highway are normal. Switching is problematic for economical operation of the device.

The present invention is intended to solve such a problem of the prior art, and in a telephone exchange equipped with a plurality of highways, even if some of the highways have a failure, only the failure point is present. It is an object of the present invention to provide a highway failure switching method that prevents the entire device from being regarded as a failure by switching the.

[0008]

FIG. 1 shows the basic configuration of the present invention. The present invention relates to a device having a plurality of in-device highways 2 for the switch unit 1,
A fault detection circuit 4 for providing a spare highway 3 in the device, dividing each highway into a plurality of sections, detecting a fault in the highway 2 in the device and outputting a fault detection signal for each section, and a fault detection signal And a switching circuit 5 for switching the in-device highway 2 in the faulty section to the backup highway 3 in accordance with the output of 1.

Further, according to the present invention, in this case, the above-mentioned fault detection circuit 4 generates a specific pilot pattern signal and sends it to the in-apparatus highway 2, and the presence or absence of the pilot pattern signal. The pilot pattern detecting section 7 generates a fault detection signal.

[0010]

In the highway failure switching system of the present invention, the highway in the device is divided into several sections, and failure detection is performed in each section. At the same time, a spare highway is provided in the device. further,
When a fault is detected, the highway in the faulty section can be switched to the spare highway.

Therefore, according to the highway failure switching method of the present invention, even if a failure occurs in a part of the highways in the telephone exchange, it is possible to switch to the spare highway in the apparatus and deal with the entire apparatus. It is possible to operate the device economically without switching to the standby system as a failure.

[0012]

FIG. 2 shows an embodiment of the present invention, showing only the ACT system. The same parts as those in FIG. 6 are indicated by the same numbers, and 14 is a backup highway, 151 _,
15 ₂ is a pilot pattern generator circuit (G) for generating a pilot pattern signal for fault detection, 16 _1,
16 ₂ is a pilot pattern checker circuit (C) for detecting the presence / absence of a pilot pattern signal, 17 _1, 17 _2, 18
Reference numerals _{1 and} 18 ₂ denote switching circuits for switching between the working highway and the backup highway.

In FIG. 2, each switching circuit 17_1,17_2,
18_1,18₂ In normal operation, switch to the working highway side.
Have been replaced. Pilot pattern generator circuit
15 _1,15₂ Always has a pilot pattern for fault detection
To generate switch signals and include switch units 11 and 12, respectively.
It is sent to each highway in the section.

Pilot pattern checker circuit 16 _1, 1
6 ₂ always detects the presence / absence of a pilot pattern signal in each highway in the corresponding section. Each pilot pattern checker circuit does not control the switching circuit when detecting the pilot pattern signal in the corresponding highway.

Now, for example, if a failure occurs in a certain highway in the section including the switch section 11, the pilot pattern signal in that highway will not be detected by the corresponding pilot pattern checker circuit, so the switching circuits 17 at both ends of the failure section. _A fault detection output is generated for _1, 18 ₁ .

As a result, the switching circuits 17 _1, 18 ₁ are
The highway is switched to the spare highway 14. Therefore, since the signal of the highway is connected to the switch unit 11 via the spare highway 14, the ACT system can continue the normal operation, and it is not necessary to switch the system to the SBY system.

FIG. 3 shows an example of the configuration of the pilot pattern generator circuit. As a pilot pattern signal, 5 frames are used for each frame on the highway.
5 (01010101) and AA (10101010) are alternately output.

In FIG. 3, 31 is a preset type counter (CNT), 32 is a shift register (SF).
R), 33 are set-reset type flip-flops (FF), 34 is a selector, 35 and 36 are D-type flip-flops (DFF), and 37 is an exclusive OR circuit.

The CNT 31 loads the initial values D0 to DX by the highway frame sync pulse HWFP and counts up by the highway clock HWCLK to determine the highway time slot into which the pilot pattern signal is inserted.

The selector 34 selects and outputs the highway data HWDATA when the FF 33 is in the reset state. The FF 33 is set by the generation of the count-up output of the CNT 31, and switches the selector 34 so that the pilot pattern signal is generated.

SFR32 consists of 8 bits, and CNT3
The operation is started by the count-up output of 1, the highway clock HWCLK is shifted, and Q8 is output at the 8th bit. This resets FF33,
Therefore, the selector 34 again determines the highway data HWDA.
The TA is output. Therefore, the pilot pattern signal is output for 8 bits per frame, that is, for only one time slot.

The DFF 35 inverts its output and feeds it back to its input, whereby the highway clock HWCL.
"0" and "1" are alternately output for each K. Also DF
The F36 inverts its output and feeds it back to the input to alternately output "0" and "1" for each frame synchronization pulse HWFP.

The exclusive OR circuit 37 includes a DFF 35 and a DFF 35.
By taking the exclusive OR of the respective outputs of the FF 36, 55 and AA are alternately output for each frame.
Therefore, the selector 34 alternately outputs 55 and AA as a pilot pattern signal for one time slot for each frame.

FIG. 4 shows a configuration example of the pilot pattern checker circuit, and illustrates the configuration when 55 and AA are used as pilot pattern signals.

In FIG. 4, 41 is a shift register (S
FR), 42 is a comparator (CMP), 43 is an inverter,
44 is a preset type counter (CNT), 45 is a D type flip-flop (DFF), 46 is an inverter, 47 is an AND circuit, 48 is a D type flip-flop (DFF), 49 is a selector, and 50 is an inverter. ..

The SFR 41 converts the highway data HWDATA at the input into parallel data by the highway clock HWCLK and outputs it. CMP4
2 compares the parallel data at the inputs A0 to A7 with the pilot pattern signal at the inputs B0 to B7, generates an output “0” when they do not match, and outputs the inverter 4
3 inverts this and outputs "1".

The CNT 44 loads the initial values D0 to DX by the highway frame synchronization pulse HWFP and counts up by the highway clock HWCLK to output corresponding to the highway time slot in which the pilot pattern signal is inserted. To occur. When the output of the CNT 44 is generated, the DFF 45 latches the output of the inverter 43 and generates a fault detection output.

When no fault detection output is generated, the AND circuit 47 generates an output for each frame synchronization pulse HWFP of the highway in response to the signal inverted through the inverter 46, whereby the DFF 48 outputs "0" and "1". Are alternately output for each frame, whereby the selector 49 selects and outputs the input of “0” and the input of “1”.

The signal from the selector 49 and the inverter 5
A signal obtained by inverting the signal after passing through 0 is input to the CMP 42 as every other eight signals. By this, 55
And AA are alternately given to the CMP 42 as pilot pattern signals for each frame.

FIG. 5 shows an example of the configuration of the switching circuit, and illustrates only the switching circuit for the ACT side. , 61 are AND circuits, 63 is an OR circuit, and 64, 65 ,.

The AND circuits 61, 62, ... Respond to the fault detection outputs 0, 1, ... From the pilot pattern checker circuits of the highways HW0, HW1 ,.
W0, HW1, ... Are connected to the OR circuit 63. The OR circuit 63 connects the switched highway to the switch unit 11 via the backup highway 14.

The selectors 64, 65, ... Always connect the highways HW0, HW1, ... To the corresponding ports of the switch section 11. Highways HW0, HW1, ...
When the fault detection outputs 0, 1, ... From the pilot pattern checker circuit are input, the spare highway 14 is selected and connected to the highways HW0, HW1 ,.

[0033]

As described above, according to the present invention, in a telephone exchange device or the like having a plurality of highways, even if a part of the highways fails, the entire device is not regarded as a failure, Only the faulty part can be switched to the backup highway. Further, if the sections are not the same section, even if a plurality of faults occur, it is possible to switch to the spare highway in each section for relief. Therefore, according to the present invention, it is possible to economically operate a telephone exchange device or the like having a plurality of highways.

[Brief description of drawings]

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

FIG. 2 is a diagram showing an embodiment of the present invention.

FIG. 3 is a diagram showing a configuration example of a pilot pattern generator circuit.

FIG. 4 is a diagram showing a configuration example of a pilot pattern checker circuit.

FIG. 5 is a diagram showing a configuration example of a switching circuit.

FIG. 6 is a diagram illustrating a conventional switching method at the time of failure in a telephone exchange.

[Explanation of symbols]

 1 Switch Unit 2 Highway in Device 3 Backup Highway 4 Fault Detection Circuit 5 Switching Circuit 6 Pilot Pattern Generation Unit 7 Pilot Pattern Detection Unit

Claims (2)

[Claims] 1. A device having a plurality of in-device highways (2) for a switch section (1), wherein a spare highway (3) is provided in the device, and each highway is divided into a plurality of sections, and each section is divided into a plurality of sections. Each time, a fault detection circuit (4) that detects a fault in the intra-device highway (2) and outputs a fault detection signal, and an intra-device highway (2) in the fault section by the fault detection signal A highway fault switching system characterized in that a switching circuit (5) for switching to (3) is provided. 2. A pilot pattern generator (6) for causing the fault detection circuit (4) to generate a specific pilot pattern signal and send it to the in-device highway (2).
2. The highway fault switching system according to claim 1, further comprising a pilot pattern detection unit (7) that generates the fault detection signal according to the presence or absence of the pilot pattern signal.