JP2629574B2 - Audio level correction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voice level correcting system, and more particularly to a voice level correcting system in a switch constituting a circuit switching network having a common channel signal network.

[0002]

2. Description of the Related Art In a conventional circuit switching network, a subscriber line composed of two lines between a local exchange and a subscriber terminal has a transmission line loss. For this reason, in the communication between the subscriber terminals, the mutual loss is added, and the level of the signal in the voice band is lowered.

[0003]

In this conventional circuit-switched network, there is a problem that if the distance of the subscriber line becomes longer, it may be difficult to hear voice during a call. Also,
In the case of facsimile, there is a problem that communication may not be possible. The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a voice level correction method for correcting a decrease in voice level that differs for each subscriber for each subscriber.

[0004]

SUMMARY OF THE INVENTION A voice level correction system according to the present invention comprises an amplifying function for amplifying a signal in a voice band to be transmitted to a subscriber terminal in an exchange constituting a circuit switching network having a common channel signal network, and an external function. A subscriber circuit having a more controllable variable PAD, a measurement function connected to the subscriber circuit via a switch for measuring a PB signal level together with a PB signal reception function, and a measurement result and a reference level by the measurement function. PB signal receiving means having a comparison function of calculating a difference by performing a comparison, and a function of transmitting level comparison value information from the PB signal reception function to a common channel signal network together with calling information, and a common line signal An extraction function for extracting level comparison value information from call information from a network and the PB
It is provided with signal receiving means and control means for controlling the variable PAD of the subscriber circuit based on information from the extracting function. In addition, the subscriber circuits (3a, 3b)
Audio from the exchange to the subscriber terminal is analyzed from digital to analog.
Logs and audio from the subscriber terminal to the exchange are added.
Digital code to convert from analog to digital /
A decoding unit (8) and an analog signal from the digital encoding / decoding unit;
An amplifier (9) for amplifying the log signal, and the amplifier
The sound signal is input and the sound is controlled by the control means (2a).
A variable PAD (10) for correcting the level of a voice signal;
The audio signal corrected by the PAD is converted into a two-line signal and added.
2-wire / 4-wire conversion unit (1
1). Also, PB signal receiver
The stage (1a, 1b) receives the PB signal at the time of calling and receives its signal.
Signal receiving circuit for sending signal information to control means (12)
And input the PB signal at the time of calling and measure the level
PB signal level measurement circuit (13), PB signal level measurement circuit
The level measured by the constant circuit is compared with the reference level.
From the comparator (14) which sends the comparison result of
It is composed.

[0005]

According to the present invention, the transmission path loss of the communication path in the two-line portion between the calling subscriber terminal and the calling exchange is corrected.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention.
In FIG. 1, reference numeral 1a denotes a PB signal receiving trunk connected to the calling subscriber terminal 6 at the time of calling, 1b denotes a PB signal receiving trunk connected to the called subscriber terminal 7 at the time of receiving a call, and 2a denotes a control unit of the calling exchange. The control unit 2a controls the variable PAD in the subscriber circuit 3a based on the level comparison value information from the PB signal receiving trunk 1a. In addition, it sends outgoing call information and level comparison value information to the common channel signaling network 5 together. 2b
Is a control unit of the destination exchange. The control unit 2b extracts the level comparison value information from the call information from the common line signaling network 5 and controls the variable PAD in the subscriber circuit 3b. 4a and 4b
Are the control units 2a and 2b of the originating exchange and the destination exchange.
Is a switch controlled by

FIG. 2 shows the subscriber circuits 3a and 3b in FIG.
FIG. 3 is a block diagram illustrating a configuration example of FIG. In FIG.
Reference numeral 8 denotes a digital encoding / decoding unit for converting voice from the exchange to the subscriber terminal during a call from digital to analog, and audio from the subscriber terminal to the exchange from analog to digital, respectively. Decoding section 8
An amplifier 10 for amplifying an analog signal from the amplifier 10 receives the audio signal output from the amplifier 9 as an input, and a variable PAD 11 for correcting the audio signal level under the control of the control unit, an audio signal corrected by the variable PAD 10 2 lines (2
2) which converts the signal to a signal of
This is a 4-wire conversion unit. The subscriber circuit 3 shown in FIG. 2 has an amplification function for amplifying an in-voice signal to be transmitted to the subscriber terminal and a variable PAD 10 which can be controlled from the outside.

FIG. 3 is a block diagram showing a configuration example of the PB signal receiving trunks 1a and 1b in FIG. This figure 3
, 12 is a PB signal receiving circuit for receiving a PB signal at the time of calling and sending the number information to the control unit, and 13 is a PB signal level measurement for receiving the PB signal at the time of calling and measuring the level of the PB signal. The circuit 14 is a comparator that compares the measurement result from the PB signal level measurement circuit 13 with the reference level 15 and outputs the comparison result to the control unit.

The PB signal receiving trunks 1a and 1b are connected to the subscriber circuits 3a and 3b via switches 4a and 4b, respectively, to measure the PB signal level together with the PB signal receiving function and the measuring function. A PB signal receiving means having a comparison function of comparing a measurement result obtained by the above with a reference level to calculate a difference. Further, the control units 2a and 2b transmit the level comparison value information from the PB signal receiving function to the common channel signaling network 5 together with the calling information and the level comparison value from the calling information from the common channel signaling network 5. An extracting function for extracting information and a control means for controlling the variable PAD of the subscriber circuits 3a and 3b based on the information from the PB signal receiving means and the extracting function.

Next, the operation of the embodiment shown in FIGS. 1 to 3 will be described. First, when making a call from a subscriber terminal, the PB signal receiving trunk 1 is connected to the calling subscriber terminal 6 by the switch 4 as is well known. The PB signal to be dialed at the time of calling is transmitted to the control unit 2 as number information by the PB signal receiving circuit 12. Further, the PB signal measurement circuit 13 measures the PB signal level, the comparator 14 compares the PB signal measurement result with the reference level 15, and outputs the level comparison value information to the control unit 2. As is well known, the control unit 2a of the originating exchange controls the switch 4 based on the number information from the PB signal receiving circuit 12 to set a path to the destination exchange.

Next, based on the level comparison value information from the comparator 14, the control unit 2a, for example, if the level of the received PB signal is lower than the reference level 15, the level is reduced by the variable PAD 10 in the subscriber circuit 3. Control to compensate for the minute. Further, it sends out the level comparison value information to the common channel signaling network 5 together with the calling information. And the control unit 2b of the destination exchange.
Extracts the level comparison value information from the call information received from the common line signaling network 5 and, based on the extracted level comparison value information, for example, if the level of the received PB signal is lower than the reference level, the subscriber circuit 3 Is controlled so as to compensate for the lowering of the level by the variable PAD 10 in the section. With the above operation, the voice level between the calling subscriber terminal and the calling exchange can be corrected.

[0012]

As described above, according to the present invention, the transmission path loss of the communication path in the two-line section between the calling subscriber terminal and the calling exchange is corrected. This has the effect that it can be guaranteed.

[Brief description of the drawings]

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

FIG. 2 is a block diagram illustrating a configuration example of a subscriber circuit in FIG. 1;

FIG. 3 is a block diagram showing a configuration example of a PB signal reception trunk in FIG. 1;

[Explanation of symbols]

 1a, 1b PB signal receiving trunk 2a, 2b Control unit 3a, 3b Subscriber circuit 4a, 4b Switch 5 Common line signal network 6 Originating subscriber terminal 7 Terminating subscriber terminal 8 Digital encoding / decoding unit 9 Amplifier 10 Variable PAD 11 2-wire / 4-wire converter 12 PB signal receiving circuit 13 PB signal level measuring circuit 14 Comparator 15 Reference level

Claims (3)

(57) [Claims] 1. An exchange comprising a circuit switching network having a common channel signal network, an amplification function for amplifying a signal in a voice band transmitted to a subscriber terminal, and a variable PA controllable from the outside.
D, a subscriber circuit connected to the subscriber circuit via a switch, a measuring function for measuring a PB signal level together with a PB signal receiving function, and comparing a measurement result obtained by the measuring function with a reference level to obtain a difference. PB signal receiving means having a comparing function of calculating the PB signal, a function of transmitting the level comparison value information from the PB signal receiving function to the common channel signaling network together with the calling information, and a call originating from the common channel signaling network. An audio level correction system comprising: an extraction function for extracting level comparison value information from information; and a control means for controlling a variable PAD of the subscriber circuit based on the PB signal receiving means and information from the extraction function. 2. A communication system according to claim 1, wherein said subscriber circuit is provided in a direction from an exchange during a call to a subscriber terminal.
Audio from digital to analog and subscriber terminals
From analog to digital from the switch to the exchange
A digital encoding / decoding unit for converting
Amplifier for amplifying analog signal from encoding / decoding unit
And the audio signal amplified by the amplifier,
Variable P for correcting the level of the audio signal under the control of the control means
AD and the audio signal corrected by the variable PAD
2-line / 4-line conversion to be converted to a signal and sent to the subscriber terminal
Sound level correction characterized by comprising a conversion unit
method. 3. The PB signal receiving means according to claim 1, wherein said PB signal receiving means receives a PB signal at the time of calling.
Signal receiving circuit for sending number information to the control means
And input the PB signal at the time of calling and measure the level
PB signal level measurement circuit and PB signal level measurement circuit
The level measured on the road is compared with the reference level, and the ratio
And a comparator for sending a comparison result to the control means.
A sound level correction method characterized by the following.