JPH05327652A - Reception data processing system - Google Patents

Abstract

PURPOSE:To improve the efficiency of voice communication by inserting data the same as frame synchronization data to a frame of facsimile data at a position corresponding to voice frame synchronization data so as to detect frame synchronization. CONSTITUTION:One frame of voice data inversely converted by a frame converter consists of data of 1st 0-3rd phases in facsimile and voice data communication equipment communicating facsimile data or voice data to a line through changeover and the 3rd phase data at the prescribed position have frame synchronization data A. Then same data B4 as the voice frame synchronization data A are inserted to a frame of the facsimile data at a position corresponding to the voice frame synchronization data together with facsimile frame synchronization data B1-B3 for the frame synchronization detection processing of the facsimile and voice data. Thus, no out of frame synchronism takes place and even when the voice communication is selected again from the facsimile communication, it is not required for synchronization locking.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing received data used in a device for switching facsimile data and voice data and communicating via a line.

[0002]

2. Description of the Related Art With the recent demand for higher efficiency and more multifunctional voice coding / decoding processing, there is a demand for a method of switching between voice communication and facsimile communication at a low rate bit. For this reason, the encoded voice and facsimile data are transmitted by the time division multiplexing apparatus or the like, but it is necessary to detect the frame synchronization when decoding the frame data output from the time division multiplexing apparatus or the like. ..

By the way, in a conventional apparatus for switching between facsimile data and voice data, frames of facsimile data and voice data are individually constructed. And
In the case of a voice data frame, if a bit error or the like has a small effect, a frame synchronization bit of 1 bit is inserted once in several frames. Although four frame synchronization bits are inserted, out-of-synchronization detection is performed by a detector provided separately for voice data and facsimile data.

[0004]

However, in such a conventional apparatus, when the voice communication is switched to the facsimile communication, the synchronism of the voice frame is detected. This is because during the communication of facsimile data,
This is because the facsimile data is naturally input to the device, but the out-of-sync detector of the voice frame is not aware of whether it is facsimile data or voice data, so the frame synchronization bit of the voice data that is normally detected cannot be detected. ..

Therefore, when the voice data is switched to the facsimile data, an out-of-synchronization of the voice frame is generated as an alarm, and when the facsimile data is switched to the voice data next, it is necessary to perform the synchronization pull-in again. It was Further, even when the facsimile data is switched to the voice data, there is a problem that an alarm is similarly generated in detecting the out-of-synchronization of the facsimile.

The present invention has been made in view of such circumstances, and prevents (masks) the out-of-sync detector on the voice side from generating an alarm when voice data is switched to facsimile data. Then, when the facsimile data is switched to the voice data next time, it is possible to provide a reception data processing method which does not require the synchronization pull-in again.

[0007]

SUMMARY OF THE INVENTION The present invention provides a facsimile and voice data communication apparatus for switching between facsimile data and voice data and communicating via a line,
When the data is received from the line, the voice frame synchronization data A is inserted at a predetermined position of the voice data frame, and the same data B4 as the voice frame synchronization data A is voiced in the frame of the facsimile data together with the facsimile frame synchronization data B1 to B3. It is intended to provide a received data processing method characterized in that it is inserted into a position corresponding to frame synchronization data, and then frame synchronization detection processing of facsimile and voice data is performed.

[0008]

The frame of the facsimile data has the same data B4 at the same position as the voice frame synchronization data A.
Therefore, even during communication of facsimile data, the same sync data B4 as the voice frame sync data A is detected in the fax frame in the voice frame detection processing.
Frame synchronization is not lost. Next, even if the facsimile communication is switched to the voice communication, it is not necessary to newly perform the synchronization detection.

Further, in the facsimile communication, when the communication is switched from the voice communication, it is necessary to perform the synchronization detection as in the conventional case, but the detection time is shorter than that of the voice frame, and in the case of the facsimile, Can be resent, so this is not a problem.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the embodiments shown in the drawings. This does not limit the invention. FIG. 1 is a block diagram showing an embodiment of the present invention. In FIG. 1, reference numeral 1 is a high-efficiency voice encoding / decoding device, which comprises an encoder 9 for transmitting data, an out-of-sync detector 10 for receiving data, and a decoder 11 for receiving voice data.

Reference numeral 2 denotes an out-of-synchronization detector for received facsimile data, and 3 a facsimile repeater. The facsimile repeater 3 has a function of detecting transmitted / received facsimile data and a function of detecting facsimile data.

Reference numerals 4 and 5 are selectors, 6 is a frame converter for performing frame conversion and transmission conversion for a time division multiplexer, 7 is an A / D converter for converting analog data from a telephone terminal and a facsimile terminal into digital data,
8 is D / for converting digital data to analog data
An A converter, 12 is an echo canceller, and 13 is an interface for transmitting / receiving data to / from a high-speed dedicated line (line).

FIG. 2 is a structural diagram of a frame format of voice data and facsimile data which are inversely converted by the frame converter 6, and one frame of voice data (10
ms) is composed of 0th to 3rd phase data, and each phase data has 20 samples (2.5 ms). The third phase data is provided with a frame synchronization bit A of only 1 bit at a predetermined position, and this bit A is an alternating pattern of 0 and 1 which changes like 0, 1, 0, 1 ... For each frame. ..

Further, one frame of the facsimile data has a length of 2.5 ms (1/4 of the voice frame) corresponding to each phase of the voice frame, has 20 samples, and has a frame synchronization bit B for each frame. .. The frame sync bit B is 4-bit data, that is, the data B.
1 to B4, data B1 to B3 are fixed patterns (for example, 1, 1, 0) used for frame synchronization detection of facsimile data, and data B4 (1 bit) changes every 4 frames. This is an alternating pattern of 1 and 1. That is, the data B4 is 0,0,0,0,1,
It changes like 1,1,1,0,0,0,0,1,1,1,1.

In such a configuration, the input analog data (voice or facsimile) passes through the A / D converter 7, is digitally converted and is input to the echo canceller 12 and the facsimile repeater 3. At this time, if the input data is facsimile data, the facsimile repeater 3 detects that it is facsimile data and switches the selectors 4 and 5 to the FAX data side.

If the input data is voice data,
The data passed through the echo canceller 12 is encoded by the encoder 9, passes through the selector 5, is frame-converted by the frame converter 6 for the time division multiplexer, and is sent to the opposite station side via the interface 13. ..

On the other hand, the data received from the player side via the interface 13, that is, the data of the time division multiplexing device frame is inversely converted into the data of the frame format shown in FIG. 2 by the frame converter 6, and each synchronization is lost. After the frame synchronization is detected by the detectors 2 and 10, the audio data is decoded by the decoder 11 and output as analog data via the selector 4 and the D / A converter 8.

If the data is facsimile data, it is detected by the facsimile repeater 3, and the selector 4 is switched to the facsimile data side accordingly. Therefore, the facsimile data passing through the facsimile repeater 3 passes through the selector 4 and undergoes D / A conversion. It is output as analog data via the device 8. In this case, the frame configuration shown in FIG. 2 can be used to mask (prevent) out-of-frame synchronization of voice data even during facsimile communication, and synchronization pull-in is performed again even when the facsimile data is switched to voice data. No need.

That is, since the frame of the facsimile data is provided with the same data B4 (alternating pattern of 0 and 1) at the position corresponding to the voice frame synchronization data A, the out-of-sync detector 10 detects that the facsimile frame is in the middle of the facsimile frame even during the communication of the facsimile data. Since the same synchronization data as the audio frame synchronization data is detected, the frame synchronization loss is not detected. Further, even if the facsimile communication is switched to the voice communication, it is not necessary to newly detect the synchronization of the voice frame.

When the voice communication is switched to the facsimile communication, the out-of-sync of the voice frame is masked as described above, so that the internal coefficient of the high-efficiency voice encoder / decoder 1 (coefficient used for encoding operation). Can be initialized and optimized for the next process.

[0021]

According to the present invention, even when the voice communication is switched to the facsimile communication, the frame synchronization on the voice side is not lost, and the synchronization pull-in is required even when the facsimile communication is switched to the voice communication again. Therefore, efficient voice communication becomes possible.

[Brief description of drawings]

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

FIG. 2 is a configuration diagram of a frame format according to an embodiment.

[Explanation of symbols]

 1 High-efficiency voice encoding / decoding device 2 Out-of-sync detector 3 Facsimile repeater 4, 5 Selector 6 Frame converter 7 A / D converter 8 D / A converter 9 Encoder 10 Out-of-sync detector 11 Decoding Device 12 echo canceller 13 interface

Claims (1)

[Claims] 1. A facsimile and voice data communication device for switching between facsimile data and voice data and communicating via a line, wherein voice frame synchronization data (A) is placed at a predetermined position of a frame of voice data when data is received from the line. ) Is inserted into the frame of the facsimile data and the same data (B) as the voice frame synchronization data (A) together with the facsimile frame synchronization data (B1 to B3).
4) A receiving data processing method characterized by inserting 4) into a position corresponding to voice frame synchronization data, and then performing frame synchronization detection processing of facsimile and voice data.