JPS592477A - System for testing digital signal generator - Google Patents

Abstract

PURPOSE:To measure simply and accurately an output of a signal generator, by measuring an output of a multiplex separation gate passing a specific time slot of a time division exchange output on a multiplex line at a digital signal test device. CONSTITUTION:Outputs of an audible signal generator 1 and a multi-frequency signal generator 2 generating respectively a digital signal are transmitted to an optional time slot TS on the 1st multiplex line 6 with a multiplexer 3. The signal on the line 6 is connected to the 2nd multiplex line 8 via a time division switch 7 to be corresponded to an optional TS and a signal of each TS on the line 8 is separted and extracted to an optional TS with an FF10A of a multiplex separating device 9. The device 9 is provided with a multiplex separating control circuit 11, an output of the circuit 11 according to an external command controls a multiplex separating FF10B to pass a specific TS on the line 8. An output of the FF10B is inputted to a digital signal test circuit 13 and a decoder 14, the circuit 13 tests the frequency an level of the digital signal for displaying it and the audible tone of the output of the decoder 14 is confirmed at a receiver 15.

Description

[Detailed description of the invention] The invention relates to an audio signal used in a time division switch.

The present invention relates to a digital signal generator test method for testing the normality of an output signal of a digital signal generator that outputs a multi-frequency signal or the like as a digital value.

Conventionally, in order to test the normality of this type of digital signal generator, a communication path test device was connected to the subscriber circuit of the exchange and a pseudo call was generated from the communication path test device. A method is adopted in which the communication path testing device receives and tests various audible signals, multi-frequency signals, etc. generated in the process by performing a general switching operation. Therefore, the test operation takes time, and since the signal is received in a decoded state as an analog signal, the only way to check the signal is to check the signal that has been attenuated or modified in the subscriber circuit, code decoding circuit, etc. Can not. That is, there are disadvantages in that the test requires time and it is not possible to accurately measure the output of the signal generator.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the above-mentioned conventional drawbacks and to provide a digital signal generator testing method that allows the output of a signal generator to be easily and accurately measured or audibly confirmed.

The test method of the present invention includes a digital signal generator that generates a digital audible signal, a digital multi-frequency signal, etc., and
a multiplexer that sends the output signals of these signal generators to arbitrary time slots on a first multiplex line;
a time division switch that connects any time slot on the multiplex line and any time slot on another second multiplex line, and separates any time slot on the second multiplex line; a time-division switching device for extracting a multiplexer and a demultiplexer, the multiplexer and demultiplexer including a demultiplexer gate that allows a specific time slot on the second multiplex line to pass through under the control of a demultiplexer control circuit; The demultiplexing control circuit is characterized in that it controls the demultiplexing gate by an external command to input the signal of a specific time slot on the second multiplexing line to a digital signal test circuit and/or a decoder. .

Next, the present invention will be explained in detail with reference to the drawings.

The figure is a block diagram showing one embodiment of the present invention. The audible signal generator 1 is a digital signal generator that digitizes and outputs audible signals such as dial tones, busy tones, and ringback tones, and the multifrequency signal generator 2 is a digital signal generator that generates digitized multifrequency signals. It is a signal generator. These digital output signals 3A and 3B are sent out to arbitrary time slots on the first multiplex line 6 via gates 4A and 4B, respectively, and supplied to the time division switch 7. Multiplex control circuit 5 has gate 4A.

The above operation is controlled by opening/closing control of 4B.

Multiplex control circuit 5 and gates 4A and 4B are built into multiplexer 3. The time division switch 7 is a switch that connects a signal on an arbitrary time slot on the first multiplex line 6 to an arbitrary time slot on the second multiplex line 8. The signals on each of the time slots 8 are separated and input by a demultiplexing flip-flop 10A in the demultiplexing device 9 to a code decoder, digital trunk, etc. (not shown) corresponding to each time slot. The above is similar to the configuration of a general time division switch, but in this embodiment, the demultiplexer 9
A demultiplexing flip-flop IOB is provided therein, which is a demultiplexing gate that allows the signal of a predetermined specific time slot on the second multiplexing line 8 to pass through under the control of the demultiplexing control circuit 11. The demultiplexing control circuit 11 controls the general demultiplexing operation of the demultiplexing flip-flop IOA, and also controls the demultiplexing flip-flop 10) 3 based on an external command to The signal is input to the digital signal test circuit 13 and decoder 14 via the test lead-in line 12.

The digital signal test circuit 13 has a function of measuring and displaying the frequency, level, sending cycle, etc. of the input digital signal. The decoder 14 also converts the input digital signal into an analog signal. The maintenance person can check the signal sound by the display on the test circuit 13 or by hearing using the receiver 15. Now, for example, when trying to test the normality of the audible signal generator 1, the maintenance person can check the signal sound by inputting a command. The multiplexing control circuit 5 controls the multiplexing gate 4A to insert the digital output signal 3A into a specific time slot on the first multiplexing line 6.

The digital output signal 3A is inserted into a predetermined specific time slot on the second multiplex line 8 via the time division switch 7. Then, the demultiplexing control circuit 11 controls the demultiplexing flip-flop 10 by a command.
B is controlled to input the signal on the specific time slot to the digital signal test circuit 13 and decoder 14.

That is, the digital output signal 3A output from the audible signal generator 1 is input to the digital signal test circuit 13. The test circuit 13 tests and displays the frequency, level, etc. of the digital signal. Also, the output of the decoder 14 is transmitted to the receiver 1.
It is also possible to confirm by b. In this embodiment, since the output signal of the digital signal generation circuit is measured as a digital value, it is not affected by attenuation, etc., and accurate measurement is possible. Further, unlike the conventional method, there is no need to generate a pseudo call, improving operability and making testing easier.

Also, a decoder allows audible confirmation, but the decoder is not an essential component of the present invention.

In the figure, 1...audible signal generator, 2...multifrequency signal generator, 3...multiplexer, 3A, 3B...digital switch, 8...second multiplex line , 9... Demultiplexing device, IOA, 10.B... Demultiplexing flip-flop, 11... Demultiplexing control circuit, 12... Test lead-in line, 13... Digital signal test circuit, 14...・
-Decoder, 15...receiver.

Agent: Patent attorney: 1) Sou Toshi

Claims (1)

[Claims] a digital signal generator that generates a digital audible signal, a digital multifrequency signal, etc.; a multiplexer that sends the output signals of these signal generators to any time slot on a first multiplex line; a time division switch that connects any time slot on one multiplex line and any time slot on another second multiplex line; and In a time division switch equipped with a demultiplexing device for separating and extracting,
The demultiplexing device includes a demultiplexing gate that allows a specific time slot on the second multiplexing line to pass under the control of a demultiplexing control circuit, and the demultiplexing control circuit controls the demultiplexing gate according to an external command. A digital signal generator testing method characterized in that the signal of a specific time slot on the second multiplexed line is inputted to a digital signal testing circuit and/or a decoder by controlling.