JP2979751B2 - Diagnosis method of PCM multiple call highway - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PCM multiplex communication highway diagnostic system, and more particularly, to a PCM multiplex communication highway capable of diagnosing a communication path even during a call and enabling a failure in the communication path to be found immediately. Diagnosis method.

[0002]

2. Description of the Related Art The configuration of a communication path system of a conventional digital switching system will be described with reference to FIG.

The digital switching system has a common rack 1 as a control unit and port racks 2a, 2b,.
, and the common rack 1 and each of the port racks 2a, 2b,..., 2n are connected by multiple communication highways (communication paths) 3a, 3b,.

The common rack 1 includes a main control unit (hereinafter, referred to as MCPU) 1a and a transmission control unit (hereinafter, referred to as HWC) 1b, which are connected by a data bus 1c. ing. The MCPU 1a controls the operation of the entire system and manages the HWC 1b. The HWC 1b controls a communication path system, and
By controlling a memory switch in the multi-channel multi-channel highway connected to the trunk of each port rack, exchange processing is performed.

Next, a conventional diagnostic method for a communication path system of the digital exchange system having the above-described configuration will be described with reference to FIG. When diagnosing the communication system,
A diagnostic trunk is connected to one of the port racks 2a, 2b,..., 2n, and an arbitrary trunk connected to a communication path system to be diagnosed is designated. Now, it is assumed that the diagnostic trunk is connected to the trunk 5 of the port rack 2a and the trunk 6 of the port rack 2b is designated.

FIG. 7 is a block diagram showing the connection at this time, and the diagnostic trunk 5 and the trunk 6 are connected via the multiple communication highways 3a, 3b and the HWC 1b. The diagnostic trunk 5 includes, for example, a single sound source 5a that outputs a signal of 400 Hz, a codec 5b, and a detector 5c that detects a return signal. Also,
The trunk 6 includes a codec 6a, a hybrid 6b,
It comprises a diagnostic switch 6c. The input / output line 6d connected to the hybrid 6b is connected to a terminal (not shown). The diagnostic switch 6c may not be provided, or may be provided, depending on the diagnostic method.

First, a description will be given of an operation when diagnosing a communication path system using a trunk having no diagnostic switch 6c. First, for example, 400H from the single sound source 5a
The signal of z is output. Then, this signal is coded by the codec 5b and sent to the HWC 1b via the communication path. The HWC 1b exchanges data with the trunk 6. As a result, the 400 Hz signal is sent to the trunk 6 via the communication path, and the trunk 6 decodes this signal with the codec 6a. This signal is input to the hybrid 6b.

The hybrid 6b transmits the input signal to the line in the counterclockwise direction.
Most of the signal of z is sent to the input / output line 6d,
A small signal leaks on line 6e. This leak signal passes through the codec 6a and the communication path, and is sent to the diagnostic trunk 5 via the HWC 1b and the communication path. The codec 5b of the diagnostic trunk 5 decodes the input signal and sends it to the detector 5c. When the detector 5c detects 400 Hz, it is determined that the communication channel system is normal. On the other hand, the 400 Hz
Is not detected, it is determined that the communication path system is abnormal.

When a communication path system is diagnosed using a trunk provided with a diagnostic switch 6c, the diagnostic switch 6c is turned on at the time of diagnosis. For this reason, the signal of 400 Hz is turned back by the diagnostic switch 6c and returns to the diagnostic trunk 5c. Therefore, a signal that is hardly attenuated is input to the detector 5c of the diagnostic trunk 5. Therefore, it is possible to diagnose the communication path system even if the detector 5c having much lower accuracy is used.

[0010]

However, the above-mentioned conventional diagnostic system has the following problems.

(1) In the case of the system using the return signal of the hybrid 6b, since the returned signal is weak, an accurate detector is required.

(2) In the case of the system using the diagnostic switch 6c, an on / off control device is required, and the control is troublesome.

(3) If the above diagnosis is performed while a call is being made using the trunk 6, the 400 Hz is mixed into the call path, which hinders the call. Therefore, the diagnosis cannot be performed during a call.

(4) Normally, since the trunk operates for 24 hours, it is very difficult to diagnose.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned problems of the conventional system, eliminate the need for an accurate detector as described above, and provide a highly reliable PCM multi-way highway capable of performing diagnosis at any time. To provide a diagnostic method.

[0016]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a replacing means for replacing highway monitoring data with the least significant bit of an arbitrary channel of a sending multiplex communication highway, and a receiving multiplex communication highway. Detecting means for detecting whether or not the data returned via the highway monitoring data is the same as the highway monitoring data, and determining means for determining whether or not the multiple call highway is normal or abnormal according to the result of the detecting means. There is a characteristic in that.

[0017]

According to the present invention, an arbitrary channel of the transmission multiplex communication highway is selected, and the least significant bit of the channel is replaced with highway monitoring data. The detecting means detects whether the highway monitoring data returned via the receiving multiplex call highway is normal, and reports the result to the determining means. The determination means determines that a failure has occurred in the multiple call highway when the detection result of the detection means is continuously abnormal.

In the present invention, since highway monitoring data is inserted into the least significant bit of the digital voice signal of the channel, the influence on the voice signal is insignificant. Diagnosis can be performed.

Therefore, the occurrence of a fault in the communication path can be immediately detected, and a highly reliable communication path can be provided.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows a block diagram of one embodiment of the present invention.
In the figure, reference numeral 11 denotes an HWC arranged on a common rack.
And 21 indicates one of the trunks arranged on the port rack.

The HWC 11 is an MCPU (not shown)
CPU connected to data bus 1a (see FIG. 6)
12, a memory switch 13 for exchanging call data, a timing generation circuit 14 for outputting a timing signal a, a clock generation unit 15 for generating a clock signal, a signal from the memory switch 13 and the clock based on the timing signal a Switching circuit 1 for switching and outputting
6 and a comparison circuit 17. The timing generation circuit 14 can be composed of, for example, a counter and a gate circuit, and is configured to be able to generate, for example, an L-level signal at an arbitrary timing of an arbitrary channel among a plurality of channels.

On the other hand, the trunk 21 includes first and second codecs 22 and 24, a hybrid 23, and a gate circuit 25.

The HWC 11 and the trunk 21 are connected by a transmission multiplex communication highway 31 and a reception multiplex communication highway 32. 33 is a timing signal line.

Next, the operation of this embodiment will be described. First,
The operation when the HWC 11 is performing a normal replacement process will be described. At this time, the operation of the timing generation circuit 14 is stopped, and for example, the H level signal is always output. For this reason, the switching circuit 16
Output is selected.

Now, assuming that communication is being performed between the caller A (terminal 40) and the other party B (not shown), a call is transmitted from the caller A as shown in FIG. The received call data passes through the receiving multiplex call highway 32, and is stored in the first memory 13a in the memory switch 13, for example, at address 0.
00H is temporarily stored. Similarly, the call data transmitted from the other party B is stored, for example, at the address 110H.

Next, the data stored at the address 000H is transferred to the destination address 110H of the second memory 13b, while the data stored at the address 110H is stored at the address 000H of the caller A.

The data at the address 000H stored in the second memory 13b is then transmitted to the trunk 21 via the switching circuit 16 and the transmission multiplex highway 31, and transmitted from the trunk 21 to the terminal 40. On the other hand, the data stored in the address 110H of the second memory 13b is sent to the terminal of the other party B via another trunk. As a result, a call is made between the caller A and the other party B.

Next, the operation of diagnosing the multiple call highway will be described. The CPU 12 in the HWC 11 activates the timing circuit 14, and the timing circuit 14
Controls the timing circuit 14 so as to output a timing signal of a predetermined level at the timing when the digital audio data of the least significant bit of the channel to be diagnosed is output from the memory switch 13.

In this embodiment, the memory switch 13
Has the ability to perform 128 channel switching, as shown in FIG. Each channel is composed of 8-bit coded data D0, D1,..., D7. Here, it is assumed that D0 is data of the most significant bit (MSB) and D7 is data of the least significant bit (LSB).

Now, when diagnosing the n-th channel,
As shown in FIG. 3, the timing generation circuit 14 outputs the L-level signal a at the timing when the data D7, which is the LSB of the n-th channel, is output from the memory switch 13.
Is output. As an example, the timing generation circuit 14 is reset by a start pulse output only when the first audio data D0 of the 0th channel is sent out,
The output pulse of the audio data D output from U12 is counted, and when the number of pulses of the data D7, which is the LSB of the n-th channel, is counted, the L-level timing signal a may be output. .

When this L-level signal is output from the timing generation circuit 14, the switching circuit 16 outputs the clock b output from the clock generation section 15 during the L-level period.
Select Further, the gate circuit 25 in the trunk 21 is turned on.

Therefore, assuming that the timing signal a is at L level during the period from time t0 to t5 in FIG.
During this period, the clock b is transmitted to the trunk 21 via the switching circuit 16 and the transmission multiplex highway 31. Next, the clock b passes through the gate circuit 25 and the receiving multiplex communication highway 32, and is delayed for a short time, so that the comparison circuit 1
Enter 7

The comparison circuit 17 compares the signal input via the receiving multiplex call highway 32 with the clock output from the clock generator 15. Then, the comparison result is reported to the CPU 12. For example, as shown in FIG. 5, the comparison circuit 17 outputs the times t1, t2, t3.
, T4 a plurality of times, and the CPU 12 determines that a speech path failure has occurred if the results of the non-coincidence are continuously obtained. Note that when a mismatch result is obtained continuously, the CPU 1
2 is determined to be a speech path failure because the result of the comparison circuit 17 may be inconsistent even if the speech path is normal due to the transition timing of the clock from H to L or vice versa. is there.

As described above, according to the present embodiment, the diagnosis is performed using the LSB of the n-th channel. Therefore, even if the n-th channel is busy, the communication data is not affected. The impact of this is insignificant. Therefore, according to the present embodiment, it is possible to monitor or diagnose the multiple call highway at any time, and the effect is great when applied to a digital switching system used for 24 hours.

[0035]

As is apparent from the above description, according to the present invention, the least significant bit of the digital audio signal of an arbitrary channel of the multi-channel multiplex communication highway is used as highway monitoring data. It is possible to monitor a communication path whether or not a call is in progress.

Further, since the communication path can be diagnosed in real time, the occurrence of a failure can be detected immediately, and the reliability of the communication path can be improved.

The diagnostic signal (ie, clock) is
Since it returns through the gate circuit of the trunk, there is an effect that a comparison circuit having a simple and inexpensive configuration can be used.

Further, since the gate circuit is turned on and off by a timing signal, the control is simple.

Further, since the diagnosis can be performed even when a call is being made using the trunk, it is suitable for the diagnosis of the communication path system of the digital switching system which operates for 24 hours.

[Brief description of the drawings]

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

FIG. 2 is an explanatory diagram of an n-channel digital audio signal.

FIG. 3 is a time chart showing a relationship between an n-th channel digital audio signal and a timing signal.

FIG. 4 is an explanatory diagram of an operation of a memory switch.

FIG. 5 is an operation explanatory diagram of the comparison circuit of FIG. 1;

FIG. 6 is a block diagram showing a configuration of a communication path system of a conventional digital exchange system.

FIG. 7 is a block diagram of a conventional PCM multiplex call highway diagnostic method.

[Explanation of symbols]

11: Transmission control unit (HWC), 12: CPU, 1
3 ... memory switch, 14 ... timing generation circuit, 15
... Clock generator, 16 switching circuit, 17 comparison circuit, 21 trunk, 25 gate circuit, 40 terminal.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04Q 11/04 H04M 3/22

Claims (2)

(57) [Claims] A transmitting and receiving multiplex call highway,
A diagnostic method for a PCM multiple call highway of a PCM switching system that performs a switching process, comprising: a replacement unit that replaces highway monitoring data with a least significant bit of an arbitrary channel of the transmission multiple call highway; Detecting means for detecting whether or not the data returned via the highway monitoring data is the same as the highway monitoring data; and determining means for determining whether the multiplex call highway is normal or abnormal according to the result of the detecting means. A diagnostic method for a PCM multiplex call highway. 2. A gate circuit which is turned on at the timing of replacing highway monitoring data with the least significant bit of the channel and electrically connects the sending and receiving multiplex communication highways is provided in a trunk of the PCM switching system. 2. The diagnostic method for a PCM multiplex call highway according to claim 1, wherein: