JPH0555957A - Voice processing unit - Google Patents

Abstract

PURPOSE:To eliminate sound quality deterioration of an incoming PCM data and an outgoing high efficient coding voice signal in the case of occurrence of the reflected high efficient coding voice signal at the time of the voice talking between a mobile set and a stationary telephone set with respect to the voice processing unit at a base station utilized in the digital mobile communication field. CONSTITUTION:In the case of occurrence of a reflected high efficient coding voice signal at the time of the voice taking, an echo canceller 7 is turned off by a control signal 15 from a control interface 12 so as to allow an outgoing PCM data 6 to bypass the canceller 7 into an echo canceller output 8 and the output 8 is subject to coding processing by an encoder 9. Thus, erroneous echo estimate due to feedback not being the usual using state of the echo canceller is stopped thereby eliminating the deterioration in the sound quality of an outgoing high efficient coding voice signal 10 and an incoming PCM data 5. As other method, either an output of the echo canceller 7 or the outgoing PCM data 6 is selected by using a reflection setting signal from the control interface and the selected signal may be inputted to the encoder 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station side voice processing device used in the field of digital mobile communication.

[0002]

2. Description of the Related Art In recent years, a voice processing device has been developed to be incorporated in a base station or a switching center of a digital car telephone system of each country.

FIG. 3 shows a schematic structure of a conventional speech processing apparatus. In FIG. 3, reference numeral 21 is an upstream high-efficiency coded audio signal, which is input to the return selection switch 22. 23 is a high-efficiency coded audio signal after being selected, and is input to the decoder 24. 25 is an upstream PCM
The data is also input to the echo canceller 27. 26 is downlink PCM data, which is input to the echo canceller 27. 28 is an echo canceller output, which is input to the encoder 29. Reference numeral 30 denotes a downlink high-efficiency coded audio signal, which is also input to the return selection switch 22. Reference numeral 31 is a control signal, which is input to and output from the control signal interface 32. Reference numeral 33 is a loopback setting signal, and 34 is a mode setting signal. Reference numeral 36 denotes the entire voice processing device.

The operation of the speech processing apparatus configured as above will be described below. In the digital mobile communication system, there are two modes of communication, that is, a mobile-to-fixed telephone call and a mobile-to-mobile call. The former is called a voice mode and the latter is called a one-link mode. The voice processing device 36 is controlled by an exchange (not shown), and the control signal 31 carries a mode setting signal, return information used for confirmation of fault isolation, etc., and is sent to the control signal interface 32. The control signal interface 32 uses the mode setting signal 3
The operation mode is notified to the encoder 29 and the decoder 24 through 4 and the return selection switch 22 is controlled through the return setting signal 33. The decoder 24
In the case of the voice mode and no loopback, the upstream high-efficiency coded voice signal 21 is selected and decoded as the high-efficiency coded voice signal 23, and in the voice mode and with the loopback,
The downstream high-efficiency coded audio signal 30 is selected and decoded as the high-efficiency coded audio signal 23, and 8-bit PCM (8 bits per sample) is output as the upstream PCM data 25. The upstream PCM data 25 is also input to the echo canceller 27 as a reception input. The downlink PCM data 26 is
The echo canceller 27 removes the echo generated on the fixed line network side and outputs it as an echo canceller output 28. The echo canceller output 28 is coded by the encoder 29 and output as a downlink high efficiency coded audio signal 30.

[0005]

However, in the above-described conventional voice processing apparatus, in the voice mode and with the loopback, the normal echo canceller 2 using the loopback path is used.
7 is applied to the echo canceller 27, and the echo canceller 27 makes an incorrect echo estimation, which leads to deterioration of the sound quality of the echo canceller output 28. There is a problem that the sound quality of the signal 30 and the upstream PCM data 25 deteriorates, and it becomes difficult to isolate a failure or the like.

An object of the present invention is to solve such a conventional problem, and an object thereof is to provide an excellent voice processing device which does not cause sound quality deterioration due to an echo canceller even in a voice mode and with a loopback.

[0007]

In order to achieve the above object, the present invention decodes upstream PCM data by decoding an upstream highly efficient encoded audio signal in a voice mode which is a communication mode between a mobile unit and a fixed telephone. It has a decoder to output, a function to remove the echo in the downlink PCM data generated on the fixed line network side when it is on, and an echo canceller that has a data through function when it is off, and an echo canceller output is coded in the voice mode. An encoder that outputs a downlink high-efficiency coded speech signal, and a downlink high-efficiency coded speech signal output from the encoder and an uplink high-efficiency coded speech signal transmitted from the mobile station are selectively input to the decoder. When a return signal is sent and received between the switch and the switch, and the switch is set in voice mode, the switch It switches the switch on the encoder side, and a control signal interface to turn off the echo canceller to the data through.

The present invention also provides a decoder for decoding an upstream high-efficiency coded audio signal and outputting upstream PCM data in a voice mode which is a communication mode between a mobile unit and a fixed telephone, and a downlink generated on the fixed line network side. An echo canceller for removing an echo in PCM data, an encoder for coding an echo canceller output in a voice mode to output a downlink high-efficiency coded voice signal, and a downlink high-efficiency coded voice signal output from the encoder. A return selection switch for switching between the upstream high-efficiency coded audio signal transmitted from the mobile device and selectively inputting to the decoder, and the downstream P
When a return signal is set in the voice mode by exchanging a control signal between the PCM data selection switch for switching the CM data and the echo canceller output and the exchange,
The return selection switch is switched to the encoder side and the PCM data selection switch is switched to down P
And a control signal interface for inputting CM data directly to the encoder.

[0009]

According to the present invention, in the above configuration, in the voice mode and the loopback, the echo canceller is turned off through the control interface to perform the data through operation, and the false echo estimation by the echo canceller is stopped. The deterioration can be eliminated, and as a result, the deterioration of the sound quality of the downlink highly efficient coded voice signal and the uplink PCM data can be eliminated.

In the voice mode and with the loopback, the present invention also allows the downlink PCM data to pass without passing through the echo canceller by controlling the PCM data selection switch through the control interface. And it is possible to eliminate the sound quality deterioration of the upstream PCM data.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a voice processing device according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 is an upstream high-efficiency coded audio signal, which is input to the return selection switch 2. 3 is a high-efficiency coded audio signal after being selected and is input to the decoder 4. 5 is upstream PCM data, which is also input to the echo canceller 7. 6 is downlink PCM data, which is input to the echo canceller 7. Reference numeral 8 denotes an echo canceller output, which is input to the encoder 9. 1
0 is a downlink high-efficiency coded audio signal, which is also input to the return selection switch 2. Reference numeral 10 is a downlink high-efficiency coded audio signal, which is also input to the return selection switch 2. Reference numeral 11 is a control signal, which is input to and output from the control signal interface 12. Reference numeral 13 is a loopback setting signal, which is input to the loopback selection switch 2. A mode setting signal 14 is input to the decoder 4 and the encoder 9. Reference numeral 15 is an echo canceller on / off control signal, which is input to the echo canceller 7. 16
Indicates the entire voice processing device.

The operation of the speech processing apparatus configured as above will be described below. Voice processing device 16
Is controlled by an exchange (not shown), and control signal 1
1, a mode setting signal, return information used for confirmation of fault isolation, etc. are sent to the control signal interface 12. Control signal interface 1
2 informs the encoder 9 and the decoder 4 of the operating mode through the mode setting signal 14, and controls the folding selection switch 2 through the folding setting signal 13.
Further, the echo canceller 7 is controlled by the echo canceller on / off control signal 15 based on the return information.
The decoder 4 decodes the upstream high-efficiency coded speech signal 1 as the high-efficiency coded speech signal 3 in the voice mode and no wrapping, and also decodes the high-efficiency coded speech signal 3 in the voice mode and wrapping. After the signal 10 is selected, it is decoded as the high-efficiency coded audio signal 3 and 8-bit PCM (8 bits per sample) is output as the upstream PCM data 5. The upstream PCM data 5 is also input to the echo canceller 7 as a reception input. The downlink PCM data 6 is input to the echo canceller 7, but in the voice mode and no return, the echo canceller on / off control signal 1
Since the echo canceller 7 is turned on by 5, the echo is removed, and in the case of the voice mode and the looping back, the echo canceller 7 is turned off by the echo canceller on / off control signal 15 and the through operation is performed as it is to produce the echo canceller output 8. Is output. The echo canceller output 8 is coded by the encoder 9 and output as a downlink high efficiency coded audio signal 10.

As described above, according to the first embodiment,
Even in the voice mode and with the loopback, the echo canceller 7 is turned off by the echo canceller on / off control signal 15 from the control interface 12 to perform the data through operation, and the false echo estimation by the echo canceller 7 is stopped. The deterioration of the sound quality of the output 8 can be eliminated, and as a result, the deterioration of the sound quality of the downlink highly efficient coded audio signal 10 and the uplink PCM data 5 can be eliminated.

Next, a second embodiment of the present invention will be described with reference to FIG.
Will be described with reference to. The same components as those in the first embodiment shown in FIG. 1 are designated by the same reference numerals. In FIG. 2, reference numeral 1 is an upstream high-efficiency coded audio signal, which is input to the folding selection switch 2. 3 is a high-efficiency coded audio signal after selection, which is input to the decoder 4. 5
Is upstream PCM data and is also input to the echo canceller 7. Reference numeral 6 is downlink PCM data, which is input to the echo canceller 7 and the PCM data selection switch 17. PCM data 18 after being selected is input to the encoder 9. Reference numeral 10 denotes a downlink high-efficiency coded voice signal, which is also input to the return selection switch 2. Reference numeral 11 is a control signal, and the control signal interface 1
I / O to 2. 13 is a loopback setting signal,
It is input to the return selection switch 2 and the PCM data selection switch 17. 14 is a mode setting signal,
It is input to the decoder 4 and the encoder 9. Reference numeral 19 denotes the entire voice processing device.

The operation of the speech processing apparatus configured as described above will be described below. Voice processing device 1
9 is controlled by an exchange (not shown), and a control signal 11 is sent to a control signal interface 12 with a mode setting signal, return information used for confirmation of fault isolation, and the like. The control signal interface 12 informs the encoder 9 and the decoder 4 of the operating mode through the mode setting signal 14, and the folding selection switch 2 and the PC through the folding setting signal 13.
The M data selection switch 17 is controlled. The decoder 4
In the voice mode and no loopback, the upstream high-efficiency coded voice signal 1 is selected and decoded as the high-efficiency coded voice signal 3, and in the voice mode and with loopback, the downlink high-efficiency coded voice signal 10 is selected. Decoding processing is performed as the post-high-efficiency coded audio signal 3, and 8-bit PCM (1 sample 8 bits) is output as the upstream PCM data 5. Up P
The CM data 5 is also input to the echo canceller 7 as a reception input. The downlink PCM data 6 is in the voice mode and there is no loopback, because the loopback setting signal 13 from the control signal interface 12 connects the PCM data selection switch 17 to the contact a side.
Echo canceller output 8
Is output. The encoder 9 outputs the echo canceller output 8
Is selected and encoded as the PCM data 18. In the voice mode and with loopback, the loopback setting signal 13 from the control signal interface 12 connects the PCM data selection switch 17 to the contact b side, so that the downlink P
The CM data 6 does not pass through the echo canceller 7 and is directly coded as the PCM data 18 after being selected by the encoder 9 to output the downlink high efficiency coded audio signal 10.

As described above, according to the second embodiment,
Even in the voice mode and with the loopback, the loopback setting signal 13 from the control interface 12 controls the PCM data selection switch 17 to pass the downlink PCM data 6 through the echo canceller 7, so that the echo canceller output is not used. As a result, it is possible to eliminate the sound quality deterioration of the downlink high-efficiency coded voice signal 10 and the uplink PCM data 5.

[0017]

As described above, according to the present invention, in the voice mode and with the loopback, the echo canceller performs the data-through operation through the control interface to stop the false echo estimation by the echo canceller.
It is possible to eliminate the sound quality deterioration of the echo canceller output,
As a result, the downlink high-efficiency coded audio signal and the uplink PC
It has an effect that the sound quality deterioration of M data can be eliminated.

In the present invention, in the voice mode and with the loopback, the downlink PCM data is passed without passing through the echo canceller by controlling the PCM data selection switch through the control interface. And, there is an effect that the sound quality deterioration of the upstream PCM data can be eliminated.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of a voice processing device according to a first embodiment of the present invention.

FIG. 2 is a schematic block diagram of a voice processing device according to a second embodiment of the present invention.

FIG. 3 is a schematic block diagram of a conventional voice processing device.

[Explanation of symbols]

 1 Upstream high-efficiency encoded voice signal 2 Folding selection switch 3 High-efficiency encoded voice signal after selection 4 Decoder 5 Upstream PCM data 6 Downlink PCM data 7 Echo canceller 8 Echo canceller output 9 Encoder 10 Downstream high-efficiency encoded voice signal 11 Control signal 12 Control signal interface 13 Return setting signal 14 Mode setting signal 15 Echo canceller on / off control signal 16 Voice processing device 17 PCM data selection switch 18 PCM data after selection 19 Voice processing device

Claims (2)

[Claims] 1. A decoder that decodes an upstream high-efficiency coded audio signal and outputs upstream PCM data in a voice mode which is a communication mode between a mobile unit and a fixed telephone, and a downstream PCM that occurs on the fixed line network side when the decoder is on. Echo canceller with a function to remove echo in data and data through function when off, encoder to output echo high-efficiency coded voice signal by encoding echo canceller output in voice mode and output from encoder A control signal is exchanged between the switch and the loopback selection switch for selectively inputting to the decoder by switching between the downlink high-efficiency encoded voice signal and the uplink high-efficiency encoded voice signal transmitted from the mobile device. When the loopback is set in the audio mode, the loopback selection switch is switched to the encoder side and the echo A voice processing device having a control signal interface for turning off a canceller and allowing data to pass through. 2. A decoder for decoding an upstream high-efficiency coded audio signal and outputting upstream PCM data in a voice mode which is a communication mode between a mobile unit and a fixed telephone, and a downstream PCM data generated on the fixed line network side. Echo canceller that removes the echo of the, the encoder that outputs the downlink high-efficiency coded voice signal by encoding the echo canceller output in the voice mode, and the downlink high-efficiency coded voice signal output from the encoder and the mobile device. Between a switching switch for switching between the transmitted high-efficiency encoded voice signal and selectively inputting to the decoder, a PCM data selection switch for switching between the downlink PCM data and the echo canceller output, and a switch. When the loopback is set in voice mode by sending and receiving a control signal with the PCM while switching to the Da side
An audio processing apparatus comprising: a control signal interface that switches a data selection switch to directly input downlink PCM data to an encoder.