JPH0823320A - Transmitter for digital voice code - Google Patents

Abstract

PURPOSE:To allow the transmitter to cope even with a contract form of a special transmission speed by defining an insertion area of a digital voice code for a part of channel to an inserted position of a signaling bit so as to form a transmission signal. CONSTITUTION:An interface signal in 6312kbps with a PCM code having a frame format inserted thereto is inputted to 1st and 2nd PCM interface sections 10X, 10Y, and each of the 1st and 2nd PCM interface sections 10X, 10Y separates a PCM code in each voice channel and gives it to a code conversion section 20 and gives a signaling bit to an ADPCM interface section 30. The code conversion section 20 converts the PCM code of each voice channel into an ADPCM code and gives it to the ADPCM interface section 30. The ADPCM interface section 30 generates an interface signal in 6312kpbs with the ADPCM code inserted thereto and outputs the signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital voice code transmission apparatus, for example, a digital voice code PCM / AD.
It can be applied to an apparatus having a PCM inter-code conversion function.

[0002]

2. Description of the Related Art When voice is transmitted via a digital transmission line, it is general to transmit it by a PCM code of 64 Kbps. Recently, ADP that predicts changes in the voice waveform and encodes and transmits only the changes from the predicted values
With the development of CM (adaptive differential PCM) coding method, 6
The 32 kbps ADPCM code satisfies the requirements such as voice quality required for the 4 kbps PCM code.
Therefore, AD is performed using a digital transmission line for PCM code.
A communication system has already been proposed in which PCM codes are transmitted and more voice channels are transmitted.

Further, such conversion between the PCM code of 64 Kbps and the ADPCM code of 32 Kbps is performed by the primary group interface (1544 Kbps or 2048 Kb).
A communication system which has a transmission rate according to the ps digital interface and operates at the stage of a transmission signal has already been developed.

[0004] Here, G.C. The 761 recommendation has a transmission speed of 2048K.
32 Kbps for bps primary interface
Specifies the frame format structure of the ADPCM code of G. The 762 recommendation has a transmission rate of 1544.
32 Kbp for Kbps primary interface
s ADPCM code frame format configuration. Therefore, the PCM code / ADP is used at the stage of the digital voice code having the transmission rate of the primary interface.
The transmission device responsible for conversion between CM codes is a P of 64 Kbps.
A transmission signal according to the primary group interface including the CM code (hereinafter, a transmission signal according to the nth group interface is referred to as an nth group interface signal) follows these recommendations.
Converted to a primary interface signal including Kbps ADPCM code and output, 32K in accordance with these recommendations
A primary group interface signal containing a bps ADPCM code is converted into a general primary group interface signal containing a 64 Kbps PCM code and output.

[0005]

By the way, 6312K
In Japan, transmission and reception of digital voice codes between transmission devices facing each other by a bps digital interface (secondary group interface) are frequently performed. For example, the transmission rate of the transmission line interface between the base station and the centralized control station in the mobile communication system is 6312.
Kbps. Even when passing through such a transmission line of 6312 Kbps digital interface, 32 Kb
It is preferable to transmit the ADPCM code of ps because more voice channels can be transmitted.

However, 32 kbps ADPCM
CCITT does not recommend that a digital interface with a code inserted at a transmission speed of 6312 Kbps be recommended.

Probably because of this, a transmission device which handles a digital interface signal having a transmission rate of 6312 Kbps into which an ADPCM code of 32 Kbps is inserted has not been realized. For example, 64 Kbps PCM code and 32 Kbps
No transmission device has been developed which performs conversion between ADPCM codes of s at the stage of a digital voice code having a transmission rate according to a 6312 Kbps digital interface. 6
A PCM code of 64 Kbps and an AD of 32 Kbps are provided on the transmission line side of the device connected to the 312 Kbps transmission line.
It is preferable to install a device that performs conversion between PCM codes at the stage of a digital voice code having a transmission rate according to a 6312 Kbps digital interface, because more voice channels can be transmitted while effectively utilizing the existing equipment.

It is simply conceivable to configure the frame format of a digital interface signal having a transmission rate of 6312 Kbps into which an ADPCM code of 32 Kbps is inserted according to the frame format of a 1544 Kbps or 2048 Kbps digital interface signal recommended by CCITT. .

However, unlike the 1544 Kbps or 2048 Kbps digital interface system, the voice code (main signal) is included in the digital interface signal of the transmission rate of 6312 Kbps in which the PCM code of 64 Kbps is inserted.
Signaling bits are also defined in addition to the above. Therefore, a transmission rate of 63 with a PCM code of 64 Kbps inserted is 63.
It is also necessary to insert maintenance bits in a digital interface signal with a transmission rate of 6312 Kbps into which an ADPCM code of 32 Kbps, which is required to be compatible with the digital interface signal of 12 Kbps, is inserted.

Further, the 6312 Kbps transmission line can be contracted as a 3 Mbps high-speed digital leased line contract as a contract form, and it is required to support such contract even in compression coding transmission.

Therefore, there is a demand for a transmission device capable of transmitting and receiving a 6312 Kbps interface signal in which signaling bits are inserted in addition to a 32 Kbps voice code in a 6312 Kbps transmission line, and a 3 Mbps high-speed digital leased line contract can be easily dealt with. There is also a need for a transmission device that can.

Such a problem similarly occurs in a transmission signal according to the secondary group interface having another transmission speed and a transmission signal according to the higher order group interface having a higher transmission rate.

[0013]

In order to solve the above problems, the first aspect of the present invention is to convert a digital audio code of 64 Kbps of a plurality of channels into a digital audio code of 32 Kbps and convert it to an n-th group (n is 2 or more). ) In a digital voice code transmission apparatus for transmitting to a first transmission line according to an interface, a code compression unit for converting each of a plurality of channels of 64 Kbps digital voice code into a 32 Kbps digital voice code, and a code conversion of each channel. 32 Kb
In addition to the multiplexing unit for inserting and inserting the ps digital voice code into the transmission signal, and the insertion position of the digital voice code as well as the signaling bit insertion position of the transmission signal according to the nth-order group interface that is determined for the 64 Kbps digital voice code. It has a signaling bit insertion part which inserts the signaling bit about each channel in the position of the transmission signal which exists.

Further, the second aspect of the present invention receives the transmission signal sent from the transmission device of the first aspect of the present invention through the fourth transmission line, and from the transmission signal, 64 Kbp of a plurality of channels is received.
In a digital voice code transmission device for obtaining a digital voice code of s, a signaling bit demultiplexing unit that separates and extracts signaling bits from a received transmission signal, and demultiplexing that extracts a 32 Kbps digital voice code of each channel from the received transmission signal Section and the extracted 32 Kbps digital voice code of each channel are respectively 64 Kb
and a code decompression unit for converting into a ps digital voice code.

[0015]

When the compressed 32 Kbps digital voice code is inserted into the transmission signal according to the nth group interface intended to insert the multi-channel 64 Kbps digital voice code, the number of channels is almost doubled. Since the code can be inserted, the signaling bit cannot be inserted only by the predetermined insertion position of the signaling bit. Therefore, in the first aspect of the present invention, the insertion area of the digital voice code for some channels is This is a bit insertion position to form a transmission signal.

Here, the number of insertion channels in the transmission signal of the compressed 32 Kbps digital voice code is 64.
If the maximum number of channels that can insert a Kbps digital voice code is set, the transmission speed will be about half of the transmission speed defined for the nth-order group interface, and a special transmission speed contract form for the nth-order group interface transmission line will be obtained. Can also handle.

The second aspect of the present invention performs the symmetrical processing of the first aspect of the present invention, and the separation of signaling bits is performed based on the insertion position according to the first aspect of the present invention.

[0018]

【Example】

(A) First Embodiment Hereinafter, the present invention will be described with reference to 64Kbps PCM code and 32K
Conversion between ADPCM codes of bps is 6312 Kbps
A first embodiment applied to a digital voice code transmission apparatus which is performed at the stage of a transmission signal having a transmission rate according to a digital interface (secondary group interface) will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic structure of the first embodiment, and FIG. 2 is a PCM code 6312.
FIG. 3 is an explanatory diagram showing a frame format of a Kbps interface, and FIG. 3 shows an ADPCM code of 6312 Kbp.
It is explanatory drawing which shows the frame format of s interface.

In FIG. 1, a digital voice code transmission apparatus 1 according to the first embodiment includes a first and a second PCM interface units 10X and 10Y, a code conversion unit 20, and an ADP.
The CM interface unit 30 and each unit have a detailed configuration as shown in FIG. 4 described later.

In FIG. 1, the PCM code having the frame format shown in FIG. 2 is inserted in the first and second PCM interface units 10X and 10Y.
The interface signal of 312 Kbps is input, and the first
And the second PCM interface units 10X and 10Y respectively separate the PCM code (8 bits) of each voice channel and give it to the code conversion unit 20, and also send the signaling bit (ST bit) to the ADPCM interface unit 3.
Give to 0. The code conversion unit 20 is a PC for each audio channel.
Converts M code to ADPCM code (4 bits) and ADP
It is given to the CM interface unit 30. The ADPCM interface unit 30 uses the A of each voice channel that has been code-converted.
ADP according to the frame format of FIG. 3 is obtained from the DPCM code, the ST bit directly given from the first and second PCM interface units 10X and 10Y, and the like.
It forms and outputs an interface signal of 6312 Kbps in which a CM code is inserted.

On the contrary, 6312 Kbp in which the ADPCM code is inserted according to the frame format of FIG.
The interface signal of s is input to the ADPCM interface unit 30, and the ADPCM interface unit 30 separates the ADPCM code of each voice channel and the code conversion unit 2
In addition to being given to 0, the two sets of inserted ST bits are given to the corresponding first or second PCM interface unit 10X or 10Y, respectively. The code conversion unit 20 converts the ADPCM code of each voice channel into a PCM code,
It is given to the first or second PCM interface section 10X or 10Y which is determined by the insertion position. First and second P
The CM interface units 10X and 10Y respectively convert the code-converted PCM code of each audio channel and S.
From T bits, according to the frame format of FIG. 2, P
It forms and outputs an interface signal of 6312 Kbps in which a CM code is inserted.

FIG. 2 is an explanatory diagram showing a frame format of a 6312 Kbps interface signal in which a PCM code is inserted, which is input / output by the first and second PCM interface units 10X and 10Y.

The frame format of this interface signal is conventionally defined.

In FIG. 2, one frame (125 μs)
Is 789 bits, and 8 channels of PCM code for each channel are inserted for 96 channels and 21 bits of maintenance bits are inserted for each frame. The 21 maintenance bits consist of 16 ST bits and 5 F bits (frame bits).

A total of 16 line operation units (handling group: HG) of 6 channels each are defined. The i-th handling group HG1 is the (6i-5) th channel CH (6i-5) to 6ith. Channel CH6i. The channel arrangement on the frame has an arrangement in which the same-numbered channels of the handling groups HG1, ..., HG16 are sequentially arranged one by one. The group of the j-th channel of each handling group HG1, ..., HG16 is represented by CH # j.

The ST bits form 8 multiframes. The synchronization pattern of the multi-frame is inserted in the first multi-frame. Channel groups CH # 1, ..., CH # are included in the second, ..., Seventh multiframes.
ST bits for each of the 6 channels are inserted. In the eighth multi-frame, a game warning bit for each handling group HG1, ..., HG16 is inserted.

The F bits form 4 multiframes. 12 out of a total of 15 bits of the first to third multi-frames
The frame synchronization pattern of the interface signal is inserted into the bit, the game alarm bit is inserted into the 1-bit A bit, and the data link data is inserted into the 3-bit D bit. The error check bit of the interface signal is inserted in the fourth multiframe.

FIG. 3 shows the ADPCM interface unit 30.
631 with ADPCM code inserted into and out of
It is explanatory drawing which shows the frame format example of a 2 Kbps interface signal.

The interface signal frame format was first introduced in the first embodiment.

6312 kbps into which the ADPCM code input / output by the ADPCM interface unit 30 is inserted.
The interface signal may be the first or second signal as described above.
The PCM interface unit 10X or 10Y of the above-mentioned data is mixed. Therefore, in FIG. 3, a code “X” is given to a data portion exchanged with the first PCM interface unit 10X, and a code “Y” is given to a data portion exchanged with the second PCM interface unit 10Y. In addition, the counterpart interface unit that transmits and receives using the terms "X port" and "Y port" in the following description is the first PCM interface unit 10 as appropriate.
X or the second PCM interface unit 10Y is clarified.

In FIG. 3, this interface signal also has 789 bits in one frame (125 μs). One frame has 4 bits of ADPCM for each channel
The reference numerals are 96 channels for the X port and 96 channels for the Y port (more precisely, 4 channels are ST
(Bits have been inserted) for a total of 192 channels and 21 maintenance bits have been inserted. Note that FIG. 3B is a two-dimensional representation of the one-dimensional representation of FIG. 3A with respect to only the voice channel portion (the same applies to FIGS. 5, 8 and 9 described later). is there).

As shown in FIGS. 3A and 3B, in this first embodiment, the ADP of the channel for the X port is used.
The CM code and the ADPCM code of the channel for the Y port are alternately distributed and arranged every 16 channels. Here, a group of unit data for X port and Y port (called X port group or Y port group) X1, Y
, ..., X6, Y6 each contain two consecutive ADPCM codes of odd and even channels for the same handling group.

Here, the channel code for the X port and the channel code for the Y port are alternately dispersed and arranged in the first and second PCM interface units 10X and 10Y and the ADPCM interface unit 30. This is because the processing delay can be reduced and the processing delay times at the X port and the Y port can be made as uniform as possible. Two odd-numbered and even-numbered channel codes for the same handling group are continuously inserted into the same X-port group or the same Y-port group in the direct time slot operation mode described later. This is because the correspondence of is well taken.

6312 kbps into which the ADPCM code input / output by the ADPCM interface unit 30 is inserted
In the interface signal, the ST bit for X port is also Y
The ST bit for the port must also be included as is. As mentioned above, the maintenance bit is 2 per frame.
It is 1 bit and there are only 16 bits except F bit. In other words, there is only capacity for inserting one of the ST bit for the X port or the ST bit for the Y port.

Therefore, in the first embodiment, as shown in FIG.
As shown in (A), the ST bit for the X port is inserted in the ST bit area in the maintenance bit, and the ST bit for the Y port is inserted in the 93rd to 96th voice channel areas CH93 to CH96 for the Y port. It is supposed to be inserted.
In addition, when viewed from the handling group, since the four channels of the 16th handling group HG16 for the Y port are collapsed, the 91st and 92nd channel regions CH
91 and CH92 may not be used for transmitting the ADPCM code.

As described above, the transparency of the ST bit is realized for both the X port and the Y port.

FIG. 4 is a block diagram showing a detailed configuration of the digital voice code transmission apparatus 1 of the first embodiment.

Two 6312 Kbps interface signals in which the PCM code having the frame format shown in FIG. 2 is inserted are converted into 6312K in which the ADPCM code having the frame format shown in FIG. 3 is inserted.
The operation of converting into an interface signal of bps and the interface signal of 6312 Kbps into which the ADPCM code having the frame format shown in FIG. 3 is inserted, the PCM having the frame format shown in FIG.
The operation of converting into two 6312 Kbps interface signals in which a code is inserted will be described in order, and the configuration of each part will be clarified through this description.

In FIG. 4, the first and second PCM interface units 10X and 10Y have the same structure. The detailed configuration of the second PCM interface unit 10Y is omitted, but the first PCM interface unit 10Y is omitted.
The suffix "X" of each part code in X is replaced with "Y", and is appropriately used in the following description.

In the first PCM interface unit 10X, the 6312 Kbps first PCM interface signal input as a bipolar signal from the second transmission line L2 of 6312 Kbps is converted into a unipolar signal by the bipolar / unipolar conversion unit 11X. Is given to the frame end portion 12X. Frame end part 12X
Detects the beginning of a frame based on the F bit, or 4
Input 6 by detecting the position in multi-frame
The 312 Kbps PCM interface signal is output to the demultiplexing unit 13X, the alarm detection unit 14X, and the ST bit demultiplexing unit 15X.

The demultiplexing unit 13X demultiplexes the PCM code of each voice channel inserted in the PCM interface signal of 6312 Kbps, supplies it to the ADPCM encoder 21X in the first code converting unit 20X for the X port, and A
The DPCM encoder 21X is a PCM for each audio channel.
The code is converted into an ADPCM code and output to the multiplexing unit 31 of the ADPCM interface unit 30. The alarm detection unit 14X detects an A bit, an error check bit, a D bit, etc. in the 6312 Kbps PCM interface signal, and outputs an alarm signal indicating normality or abnormality to an alarm processing unit (not shown). ST bit separation unit 15X
Separates and extracts the ST bit inserted in the 6312 Kbps PCM interface signal and outputs it to the ST bit insertion unit 32 of the ADPCM interface unit 30.

Also in the second PCM interface unit 10Y and the second code conversion unit 20Y, a different 6312K is used.
6312K input from the third transmission line L3 of bps
Similar processing is executed for the second PCM interface signal of bps, and ADP in the second code conversion unit 20Y is executed.
The ADPCM code output from the CM encoder 21Y is given to the multiplexing unit 31 of the ADPCM interface unit 30 and S extracted and separated by the ST bit separation unit 15Y.
The T bit is given to the ST bit insertion unit 32 of the ADPCM interface unit 30.

The multiplexing unit 31 of the ADPCM interface unit 30 includes an ADPCM code for the audio channel for the X port from the ADPCM encoder 21X and an ADPC for the audio channel for the Y port from the ADPCM encoder 21Y.
The M code and the M code are arranged (multiplexed) according to the frame format of FIG. 3 and output to the ST bit insertion unit 32.

The ST bit inserting section 32 inserts the ST bit from the ST bit separating section 15X into the ST bit area of the maintenance bit in which the ADPCM code has already been inserted, and the ST bit from the ST bit separating section 15Y. , The 93rd channel to the 96th channel CH93 to C for the Y port
It is inserted into the area of H96 and output to the frame generation unit 33.

The frame generation section 33 further inserts F bits such as a frame pattern and error check bits and the like and conforms to the frame format shown in FIG.
An ADPCM interface signal of bps is formed and given to the unipolar / bipolar converter 34. Thus, the 6312 Kbps ADPCM interface signal converted into a bipolar signal by the unipolar / bipolar converter 34 is sent to the first transmission line L1 of 6312 Kbps.

On the other hand, processing in the reverse direction is performed as follows.

In the ADPCM interface unit 30, a 6312 kbps ADPC input as a bipolar signal from the 6312 kbps fourth transmission line L4.
The M interface signal is converted into a unipolar signal by the bipolar / unipolar converter 35 and given to the frame terminating unit 36. The frame terminating unit 36 detects the head of the frame based on the F bits or detects the position in 4 multi-frames, and receives the input 6312 Kb.
The ADPCM interface signal of ps is demultiplexed 3
7, output to the alarm detector 38 and the ST bit separator 39.

The demultiplexing unit 37 has an A of 6312 Kbps.
The ADPCM code of each audio channel for the X port and the Y port inserted in the DPCM interface signal is separated based on the arrangement position, and the ADPCM code of each audio channel for the X port is divided into the first for the X port. To the ADPCM decoder 22X in the code conversion unit 20X, and the ADPCM code of each audio channel for the Y port is supplied to the ADPCM decoder 2 in the second code conversion unit 20Y for the Y port.
Give to 2Y. The ADPCM decoder 22X converts the ADPCM code of each audio channel for the X port into a PCM code and outputs the PCM code to the multiplexing unit 16X of the first PCM interface unit 10X, and the ADPCM decoder 22Y outputs each audio channel for the Y port. The ADPCM code is converted into a PCM code and output to the multiplexing unit 16Y of the second PCM interface unit 10Y. The alarm detection unit 38 is 6312.
The A bit, the error check bit, the D bit, etc. in the Kbps ADPCM interface signal are detected, and an alarm signal indicating normality or abnormality is output to an alarm processing unit (not shown). The ST bit separation unit 39 has 6312 Kb.
The ST bits for the X port and the Y port inserted in the ADPCM interface signal of ps are separated and extracted, and the ST bits for the X port are output to the ST bit insertion unit 17X of the first PCM interface unit 10X,
The ST bit for the Y port is output to the ST bit insertion unit 17Y of the second PCM interface unit 10Y.

In the first PCM interface section 10X, the multiplexing section 16X arranges (multiplexes) the PCM code of the audio channel for the X port from the ADPCM decoder 22X so as to comply with the frame format of FIG.
Output to the ST bit insertion unit 17X. The ST bit inserting section 17X receives the S for the X port from the ST bit separating section 37.
The T bit is inserted into the ST bit area of the maintenance bit in which the PCM code has already been inserted and output to the frame generation unit 18X. The frame generation unit 18X further inserts F bits such as a frame pattern and error check bits to comply with the frame format shown in FIG.
A PCM interface signal of bps is formed and given to the unipolar / bipolar converter 19X. Thus, the 6312 Kbps PCM interface signal converted into a bipolar signal by the unipolar / bipolar converter 19X is sent to the 6312 Kbps fifth transmission line L5.

The second PCM interface unit 10Y also performs the same processing as that of the first PCM interface unit 10X, forms a 6312 Kbps PCM interface signal according to the frame format shown in FIG. 2, and converts it into a bipolar signal. It is sent to the sixth transmission line L6 of 6312 Kbps, which is different from the PCM interface unit 10X of No. 1.

The transmission device 1 according to the first embodiment is capable of exchanging a transmission signal with the opposite device without compression coding. That is, when the data of each channel is test data other than voice code, monitoring data, etc., it can be transmitted without compression encoding. Note that such an operation mode is called a direct time slot.

FIG. 5 shows the first 6312 kbps transmission line L.
3 shows the frame format of the transmission signal sent in No. 3 in the direct time slot. As is clear from comparison with FIG. 2, ADPCM voice code (4 bits)
In the continuous area of the odd and even channels where
Data (8 bits) such as test data and monitoring data for one odd-numbered channel is inserted.

Therefore, at the time of this direct time slot, the operation modes of the code conversion units 20X and 20Y are switched so as to allow the data to pass therethrough.
The multiplexing unit 31, the demultiplexing unit 37, and the like of the DPCM interface unit 30 execute the multiplexing process and the demultiplexing process so as to form the transmission signal according to FIG.

Therefore, according to the first embodiment, 6312K
It is possible to realize a transmission device that can perform conversion between ADPCM code and PCM code at the signal stage of the bps interface (secondary group interface) and that is transparent to ST bits. Thus, using the 6312 Kbps digital transmission line, 32 Kb
The ADPCM code of ps can be transmitted, and more voice channels can be efficiently transmitted.

Further, according to the first embodiment, the direct time slot operation mode can be easily executed if necessary. This is because the frame format in which the ADPCM code is inserted is selected as shown in FIG. 2, so that the transmission signal (frame) in the direct time slot operation mode can be easily created with the same configuration.

(B) Second Embodiment Next, the second embodiment of the digital voice code transmission apparatus according to the present invention will be described.
Examples will be described in detail with reference to the drawings.

FIG. 6 is a block diagram showing a schematic structure of the second embodiment, and FIG. 7 is a block diagram showing a detailed structure thereof. 6 and 7, the same or corresponding portions as those in FIGS. 1 and 4 described above are designated by the same reference numerals.

The transmission device 2 of the second embodiment is 6312.
This corresponds to the case where a 3 Mbps high speed digital leased line contract is contracted as a Kbps transmission line contract form.

Referring to FIG. 6, the digital voice code transmission apparatus 2 of the second embodiment has first and second PCM interface sections 10X and 10Y, a code conversion section 20, and first and second ADPCM interface sections. 30X and 30Y
And each unit has a detailed configuration as shown in FIG. 7 described later.

In FIG. 6, the PCM code having the frame format shown in FIG. 2 is inserted in the first and second PCM interface units 10X and 10Y.
The interface signal of 312 Kbps is input, and the first
And the second PCM interface units 10X and 10Y respectively separate the PCM code of each audio channel and give it to the code conversion unit 20, and also correspond to the first bit corresponding to the ST bit.
Alternatively, the second ADPCM interface unit 30X or 30
Give to Y. The code conversion unit 20 converts the PCM code of each audio channel from the first PCM interface unit 10X into A
The DPCM code is converted and given to the first ADPCM interface unit 30X, and the second PCM interface unit 10 is supplied.
The PCM code of each voice channel from Y is converted into an ADPCM code and given to the second ADPCM interface unit 30Y. The first ADPCM interface unit 30X includes
According to the frame format of FIG. 3, the ADPCM code and the ST bit are added only to the area for the X port from the ADPCM coded code of each voice channel and the ST bit directly given from the first PCM interface unit 10X. The inserted interface signal of 6312 Kbps is formed and output. The second ADPCM interface unit 30Y also follows the frame format of FIG. 3 from the ADPCM-encoded voice channel code and the ST bit directly given from the second PCM interface unit 10Y, and also for the X port. ADPCM code and ST bit are inserted only in the area 6
It forms and outputs an interface signal of 312 Kbps.

On the contrary, the 6312 Kbps interface signal from the 6312 Kbps transmission line according to the frame format of FIG. 3 and in which the ADPCM code and the ST bit are inserted only in the area for the X port is the first A
The first A is input to the DPCM interface unit 30X.
The DPCM interface unit 30X is A for each audio channel.
The DPCM code is separated and given to the code conversion unit 20, and the inserted ST bit is given to the first PCM interface unit 10X. Similarly, according to the frame format of FIG. 3, AD is applied only to the X port area.
A 6312 Kbps interface signal from a 6312 Kbps transmission line different from the above in which the PCM code and ST bits are inserted is input to the second ADPCM interface unit 30Y, and the second ADPCM interface unit 30Y outputs the ADPCM code of each voice channel. The separated ST bit is supplied to the code conversion unit 20 and the inserted ST bit is supplied to the second PCM interface unit 10Y.
The code conversion unit 20 uses the PCM to convert the ADPCM code of each audio channel from the first ADPCM interface unit 30X.
It is converted into a code and given to the first PCM interface unit 10X, and also the second ADPCM interface unit 30Y.
The ADPCM code of each audio channel is converted into a PCM code and given to the second PCM interface unit 10Y. The first and second PCM interface units 10X and 10Y respectively insert a PCM code according to the frame format of FIG. 2 from the PCM coded voice channel code and ST bit 6312.
63 Kbps interface signal is formed and corresponding
Output to the 12 Kbps transmission line.

As described above, in the transmission apparatus 2 according to the second embodiment, the data is inserted only in the X port area of the frame format shown in FIG.
Two 6s with a Mbps high speed digital leased line contract
An interface signal satisfying the contracted speed is transmitted / received to / from the 312 Kbps transmission line.

FIG. 7 in which the same or corresponding parts as in FIG. 4 are assigned the same reference numerals is a block diagram showing the detailed structure of the digital voice code transmitting apparatus 2 of the second embodiment. In the following, the first
The difference from the embodiment will be mainly described.

In FIG. 4, in the second embodiment, AD
As the PCM interface unit, the ADPC of the first embodiment
The first and second ADPCM interface units 30X and 30Y having the same configuration as the M interface unit 30 are provided.

First and second PCM interface section 1
The internal configurations and operations of 0X and 10Y, and the internal configurations and operations of the first and second code conversion units 20X and 20Y are the same as those in the first embodiment.

However, the first PCM interface section 10
The ST bits separated and extracted by the ST bit separation unit 15X of X are given to the ST bit insertion unit 32X of the first ADPCM interface unit 30X, and the S bits separated and extracted by the ST bit separation unit 15Y of the second PCM interface unit 10Y.
The T bit is applied to the ST bit insertion unit 32Y of the second ADPCM interface unit 30Y. Further, the ST bits separated and extracted by the ST bit separation unit 39X of the first ADPCM interface unit 30X are given to the ST bit insertion unit 17X of the first PCM interface unit 10X, and the ST bit separation of the second ADPCM interface unit 30Y is performed. The ST bits separated and extracted by the unit 39Y are applied to the ST bit insertion unit 17Y of the second PCM interface unit 10Y.

Further, the ADP of the first code conversion unit 20X
The ADPCM code from the CM encoder 21X is the first A
The ADPCM code is given to the multiplexing unit 31X of the DPCM interface unit 30X, and the ADPCM code from the ADPCM encoder 21Y of the second code converting unit 20Y is given to the multiplexing unit 31Y of the second ADPCM interface unit 30Y. The ADPCM code from the demultiplexing unit 37X of the first ADPCM interface unit 30X is the first
Is applied to the ADPCM decoder 22X of the code conversion unit 20X, and the ADPCM code from the demultiplexing unit 37Y of the second ADPCM interface unit 30Y is applied to the ADPCM decoder 22Y of the second code conversion unit 20Y.

First ADPCM interface section 30X
The multiplexer 31X inserts the ADPCM code of each audio channel from the ADPCM encoder 21X into the X port area in the frame format shown in FIG.
The bit inserting section 32X inserts the ST bit from the ST bit separating section 15X into the ST bit area in the maintenance bit area in the frame format shown in FIG. Similarly, the multiplexing unit 31Y of the second ADPCM interface unit 30Y inserts the ADPCM code of each audio channel from the ADPCM encoder 21Y into the X port area in the frame format shown in FIG. , ST bit from the ST bit separation unit 15Y is inserted into the ST bit area in the maintenance bit area in the frame format shown in FIG.

In this way, two 6312 Kbps ADPCM interface signals in which the Y port area becomes an empty area are formed, and the first or seventh 63th ADPCM interface signals are formed.
It is output to the 12 Kbps transmission line L1 or L7.

First ADPCM interface section 30X
The demultiplexing unit 31X receives the A of 6312 Kbps.
The DPCM interface signal is demultiplexed into the ADPCM code of each audio channel based on the channel arrangement in the X port area and output to the ADPCM decoder 22X, and ST
The bit separation unit 38X receives the received A of 6312 Kbps.
The ST bit insertion unit 1 separates and extracts the ST bit inserted in the maintenance bit area of the DPCM interface signal.
Output to 7X. Similarly, the demultiplexing unit 31Y of the second ADPCM interface unit 30Y receives the received 6312
A Kbps ADPCM interface signal is added to each voice channel based on the channel arrangement in the X port area.
The PCM code is demultiplexed and output to the ADPCM decoder 22Y, and the ST bit demultiplexing unit 38Y receives the received 6312.
The ST bits inserted in the maintenance bit area of the Kbps ADPCM interface signal are separated and extracted and output to the ST bit insertion unit 17Y.

In this way, even when two 6312 Kbps ADPCM interface signals with the Y port area being an empty area are input, various data can be appropriately extracted.

As described above, according to the transmission apparatus of the second embodiment, as the contract form of the 6312 Kbps transmission line,
Even when a 3 Mbps high-speed digital leased line contract is signed, the ADPCM code can be transmitted.

In practice, the transmission device 1 and the second device of the first embodiment
The transmission device 2 of the embodiment is realized as the same transmission device, and the number and type of ADPCM interface units (for example, racks) to be mounted are changed and wiring is appropriately changed according to the contract contents of the transmission line. By implementing the first
Alternatively, the transmission device of the second embodiment is configured.

Further, as the number of channels increases, the transmission apparatus of the second embodiment can be changed to the transmission apparatus of the first embodiment. For example, in FIG. 6 and FIG.
Although the system is shown, when only one system is used, when the number of transmission channels increases, the contract form of the transmission line is changed to the normal form, and the transmission device configuration is the configuration of the first embodiment. By switching to, it is possible to easily cope with an increase in the number of channels. For example, in a mobile communication system, the number of channels handled by a base station or a centralized control station may increase with the spread of mobile terminals, and the ease of handling such an increase in the number of channels is effective. .

(C) Other Embodiments In the above embodiments, the frame format of the transmission signal in which the ADPCM code is inserted is shown in FIG. 2, but the present invention is not limited to this, and the X port and If the conditions are that the Y ports are distributed and that the ADPCM codes of two odd-numbered and even-numbered consecutive channels of the same handling group are consecutively inserted, other frames are satisfied. It may follow the format.

Although not described, other frame formats are shown in FIGS. 8 and 9, respectively.

Further, the distributed arrangement of the X port data and the Y port data may not be executed.

Further, in the above embodiment, the compression coding system is the ADPCM system, but another compression coding system may be applied. The point is a 64 Kbps PC
Any code capable of converting the M code into a 32 Kbps code may be used.

In the above embodiment, the transmission line is 6312.
Although the interface conforming to the Kbps interface is shown, it may conform to the secondary group interface such as the 8448 Kbps interface adopted in Europe or the like, and may conform to the interface of the tertiary group or more.

In the above embodiment, 64 Kbp
The transmission device for converting between the transmission signal according to the secondary group interface in which the PCM code of s is inserted and the transmission signal according to the secondary group interface in which the ADPCM code of 32 Kbps is inserted is shown. The present invention can also be applied to a transmission device that performs conversion between a transmission signal according to a secondary group interface in which an ADPCM code of 32 Kbps is inserted and a transmission signal according to a secondary group interface. That is, the present invention can be applied to a transmission device in which audio signals of a plurality of channels are input in parallel to one input / output terminal. For example, such a device has a configuration in which the portions of the PCM interface units 10X and 10Y shown in FIG. 4 are replaced with one having a configuration for converting a voice signal into a PCM code and a configuration for forming an ST bit. .

Further, in the above embodiment, the ST bit insertion section is provided after the multiplexing section, but the order of these may be reversed.

[0083]

As described above, according to the present invention, 64K
Not only the signaling bit insertion position of the transmission signal according to the high-order group interface defined for the bps digital voice code, but also the signaling bit for each channel is inserted and transmitted at the transmission signal position defined as the insertion position of the digital voice code. By doing so, it is possible to realize a transmission device that can be transmitted by a compression code and is transparent to signaling bits. As a result, a 32 Kbps voice code can be transmitted using the transmission path of the high-order group interface, and more voice channels can be efficiently transmitted.

Further, by appropriately providing an empty channel,
As a contract form of the high-order group interface transmission line, even when a low-speed contract is contracted, the digital voice code can be transmitted.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a first embodiment.

FIG. 2 6312 Kbps with PCM code inserted
It is a frame format figure of an interface signal.

FIG. 3 6312 Kb with ADPCM code inserted
It is a frame format figure (1) of a ps interface signal.

FIG. 4 is a block diagram showing a detailed configuration of the first embodiment.

FIG. 5 is a frame format diagram of a 6312 Kbps interface signal for a direct time slot operation mode in which an ADPCM code is inserted.

FIG. 6 is a block diagram showing a schematic configuration of a second embodiment.

FIG. 7 is a block diagram showing a detailed configuration of a second embodiment.

FIG. 8: 6312 Kb with ADPCM code inserted
It is a frame format figure (the 2) of a ps interface signal.

FIG. 9: 6312 Kb with ADPCM code inserted
It is a frame format figure (3) of a ps interface signal.

[Explanation of symbols]

 1, 2 ... Digital voice code transmission apparatus, 10X, 10Y ... PCM interface section, 12X, 36, 36X ... Frame terminating section, 13X, 37, 37X ... Demultiplexing section, 15X, 39, 39X ... ST bit demultiplexing section, 16X, 31, 31X ... Multiplexing section, 17X, 32, 32X ... ST bit inserting section, 18X, 33, 33X ... Frame generating section, 20, 20X, 20Y ... Code converting section, 21X ... ADPCM encoder, 22X ... ADPCM decoder, 30, 30X, 30Y ... ADPCM interface unit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshinori Shimizu 6 Rokubancho, Chiyoda-ku, Tokyo Japan Mobile Communications Co., Ltd. (72) Inventor Yoshiaki Uchida 6 Rokubancho, Chiyoda-ku, Tokyo 6 Japan Mobile Communications Co., Ltd. Within

Claims (8)

[Claims] 1. A digital voice code transmission device for converting a digital voice code of 64 Kbps of a plurality of channels into a digital voice code of 32 Kbps and sending the digital voice code to a first transmission line according to an nth order group (n is 2 or more) interface. , A code compression unit for converting each of the 64 Kbps digital voice code of each channel into a 32 Kbps digital voice code, a multiplexing unit for multiplexing and inserting the code-converted 32 Kbps digital voice code of each channel into a transmission signal, and a 64 Kbps Signaling bit for inserting signaling bit for each channel not only at the signaling bit insertion position of the transmission signal according to the nth-order group interface determined for the digital voice code but also at the transmission signal position determined as the insertion position of the digital voice code With insertion part A digital voice code transmission device characterized by the following. 2. The digital voice code transmission device according to claim 1, wherein the digital voice code of 64 Kbps is included in a predetermined number of channels and the signaling bit of each channel is included.
A transmission signal from a second transmission line according to the next group interface is input, and a 64 Kbps digital voice code of each channel included in the transmission signal is supplied to the code compression unit and is included in the transmission signal. A first 64 Kbps interface unit for giving signaling bits to the signaling bit inserting unit; and a 64 Kbps digital voice code for a predetermined number of channels and signaling bits for each channel, n
The transmission signal from the third transmission line according to the next-group interface is input, and the 64 Kbps digital voice code of each channel included in the transmission signal is given to the code compression unit and is included in the transmission signal. A transmission device for a digital voice code, comprising: a second 64 Kbps interface unit for giving a signaling bit to the signaling bit inserting unit. 3. The digital voice code transmission apparatus according to claim 2, wherein the multiplexer is output from the first 64 Kbps interface section and the channel is digitally encoded by the code compressing section. And the second 64 Kbps
And a digital voice code of a channel, which is output from the interface unit for use by the code compression unit and is code-converted by the code compression unit, in a distributed arrangement. 4. The digital voice code transmission device according to claim 1, wherein the multiplexing unit continuously performs code-converted digital voice codes of two channels belonging to the same handling group. A digital voice code transmission device characterized by being arranged. 5. The digital voice code transmission device according to claim 1, wherein the digital voice code of 64 Kbps is included for a predetermined number of channels and the signaling bit of each channel is included.
A transmission signal from a second transmission line according to the next group interface is input, and a 64 Kbps digital voice code of each channel included in the transmission signal is supplied to the code compression unit and is included in the transmission signal. A digital voice code transmission apparatus having a first 64 Kbps interface section for giving a signaling bit to the signaling bit inserting section, wherein a transmission signal sent to the first transmission line has an empty channel. 6. A transmission signal transmitted from the digital voice code transmission device according to claim 1 is received via a fourth transmission line, and 64 Kbp of a plurality of channels are received from the transmission signal.
In a digital voice code transmission apparatus for obtaining a digital voice code of s, a signaling bit demultiplexing unit for separating and extracting signaling bits from a received transmission signal, and demultiplexing for extracting a 32 Kbps digital voice code of each channel from the received transmission signal And a code decompression unit for converting each of the extracted 32 Kbps digital voice code of each channel into a 64 Kbps digital voice code. 7. The digital voice code transmission device according to claim 6, wherein a part of the signaling bits separated by the signaling bit separation unit and a part of the channel 64 Kbps digital voice code from the code expansion unit. And from 64 Kbp
a third 64 Kbps interface unit for forming a transmission signal in accordance with an nth-order group interface including the digital voice code of s by a predetermined number of channels and including signaling bits of each channel and outputting the signal to the fifth transmission line; From the remaining signaling bits separated by the separation unit and the 64 Kbps digital voice code of the remaining channel from the code expansion unit, 64 Kbp
a fourth 64 Kbps interface unit for forming a transmission signal in accordance with an nth-order group interface including the digital voice code of s by a predetermined number of channels and including the signaling bit of each channel and outputting the signal to the sixth transmission line. Characterized digital voice code transmission device. 8. The digital voice code transmission device according to claim 6, wherein the transmission signal from the fourth transmission line has an empty channel in which the digital voice code and the signaling bit are not inserted. , Including a predetermined number of 64 Kbps digital audio codes from the signaling bits of the channels other than the empty channels separated by the signaling bit separation unit and the 64 Kbps digital audio codes of the channels other than the empty channels from the code expansion unit And a third 64 Kb which forms a transmission signal according to the nth order interface including the signaling bit of each channel and outputs it to the fifth transmission line.
A digital voice code transmission device having a ps interface unit.