JPH0260334A - Signaling pattern control system for pcm24 transmission line interface device - Google Patents

Abstract

PURPOSE:To use the number of bits transmitted by a PCM24 transmission line interface and to thus transmit many signaling patterns without giving the influence to the software processing of an exchange by providing an alternating giving encoding part, a signal multiplexing part and the like. CONSTITUTION:When 4 bits of (a)-(d) are supplied to an alternating giving encoding part 11 as a signaling bit for a voice channel from an exchange, encoding including alternating is executed. Namely, in accordance with 0 or l of a bit (c), for a bit A after conversion, an (a) bit is outputted as it is, or becomes an alternating code in which 0 and 1 are alternately changed for 12 frames. Signaling bits A and B obtained by converting with the encoding part 11 are multiplexed by a signal multiplexing part 12, inputted through a transmission line to a signal multiplexing separating part 13 of an opponent exchange, and after separation, converted to original 4 bit signals (a)-(d) with a decoding part 14. Thus, many signaling patterns can be transmitted without giving the influence to the software processing of the exchange.

Description

[Detailed Description of the Invention] [Summary] Regarding a signaling pattern control method for transmitting and receiving control signals in a PCM24 transmission line interface device, using the number of transmission bits of the PCM24 transmission line interface, a signaling pattern with a larger number than that is processed by software in an exchange. The purpose is to provide a signaling pattern control method for a PCM24 transmission line interface device that transmits without affecting p (p
> m) signaling bits are converted into a code including m-bit alternation in an alternation assigning coding unit, and the converted m-bit code is assigned to a corresponding voice code for each of the fixed number of frames in a signal multiplexing unit. It is inserted into the bit position and transmitted, and on the receiving side, m
The configuration is such that p bits of signal bits are output to the exchange by separating the signaling bits and decoding the alternating code in the decoding section.

[Industrial Application Field] The present invention relates to a signaling pattern control method for transmitting and receiving control signals in a PCM24 transmission line interface device.

Conventionally, the PCM24 transmission line interface device, which can transmit and receive 24 channels of audio data in one frame, transmits 2-bit signaling bits representing the status of each subscriber as a control signal in each of the 24 audio channels in 12 frames. It is inserted.

However, some types of exchanges use 4-bit signaling bits as control signals, and it is necessary to use a completely new equipment configuration to transmit such a number of signaling bits to and from the other exchange. Since this is costly, it is desired to be able to transmit using the existing PCM24 transmission line interface device.

[Conventional technology] A conventional explanatory diagram is shown in FIG.

A in the figure shows a connection system diagram, and the figure shows the audio signal of the PCM24 line (PC
A unidirectional configuration is shown for transmitting M codes). In the figure, reference numerals 30 and 34 represent an exchange, 31 a multiplexing unit which is a transmission line interface, 32 a transmission line, and 33 a demultiplexing unit which is a transmission line interface.

The exchange 30 accommodates subscribers (not shown) and transmission lines, and a large number of audio signals A/D-converted within the exchange are multiplexed by a multiplexer 31 serving as a transmission line interface. In that case, two control signaling bits, A and B, are used to indicate the status of the subscriber assigned to each channel.
Bits are inserted into the audio signal. The 24-channel multiplexed signal containing a control signal in each channel in the multiplexer 31 passes through the transmission path 32 and is received by the multiplexer/demultiplexer 33 of the destination exchange, where the control signaling bits are extracted and each voice signal is The signals are separated and provided to switch 34. In the exchange 34, an internal exchange control unit (not shown) controls exchange connections using the signaling bits of each channel.

FIG. 3B shows the frame structure of the PCM 24 transmission line ink face in the transmission line 32. Each frame is a 24-channel signal (audio data) as shown in frame 1.
Each channel consists of 8 bits, bits 0 to 7, as shown in a typical example as channel X (X is any one of 1 to 24) at the left end of FIG. 3B.

The subscriber's voice data transmitted through this channel Represented by signaling bits. In order to transmit these two bit signals A and B, conventionally B was used.

As shown in FIG. 2, the signal is inserted into the last bit (bit 7 position) of frame 6 and frame 12 of the corresponding channel X and transmitted. The reason why bit 7 is used is that, as is well known, it is the least significant bit of the PCM code and has little effect on speech communication. C9 in FIG. 3 shows the configuration of the above-mentioned signaling bits A and B, and four states are displayed by a 2-bit signal pattern.

[Problems to be Solved by the Invention] As described above, the PCM24 transmission line interface device that uses the conventional cedarling bit transmission method inserts a signal into the bit 7 position of a specific frame in order to transmit the 2-bit signaling focus. It had a configuration for separating it. However, in addition to the PCM24 system, there are 3
A device equipped with a function that can be used as a PCM30 transmission line capable of transmitting and receiving 0 lines (30 channels) is used. Since four signaling bits are used per line for such transmission lines, four signaling bits are also handled within the exchange.

When transmitting such a 4-bit signal using a conventional PCM24 transmission line interface device, it is desired that the processing can be performed in a manner that does not place a burden on the online software of the exchange.

The present invention is a PCM that uses the number of bits transmitted on the PCM 24 transmission path ink face to transmit a larger number of signaling patterns without affecting the software processing of the exchange.
The present invention aims to provide a signaling pattern control method for an X.24 transmission line interface device.

[Means for solving the problem] Fig. 1(a) shows a basic configuration diagram of the present invention, and Fig. 1(b) shows a basic configuration diagram of the present invention.
) shows the conversion format of the signaling bits of the present invention.

In FIG. 1(a), 11 represents an alternating coding section, 12 a signal multiplexing section, 13 a signal demultiplexing section, and 14 a decoding section.

The present invention provides three states, an alternating code state and an original binary state of 0, "1," for each signaling hit assigned to a transmission path in a PCM24 transmission path interface device.
By controlling the signaling pattern so that it takes two states, it is possible to transmit a larger number of bits of signal information without changing the number of signaling bits on the transmission path. It is processed as a level signal.

[Effect] The present invention will be described in detail with reference to FIG. 1(b).

When 4 bits a to d are supplied from the exchange to the alternation assignment encoding unit 11 as signaling bits for a certain voice channel, the alternation assignment encoding unit 11 encodes them using the conversion format shown in FIG. 1(b). conduct.

On the left side of Figure 1(b), there are four representations of the switchboard, a to d.
There are 2 bits, and by encoding them, an expression on the CM transmission path of 2 bits A and B as shown in the table on the right is generated.

Among the expressions a - d in the exchange, for a and b, '“0
" or °"1"' corresponds as is, and for c and d, four types of combinations of 0" and 1" are expressed. For the combination of signaling bits like the one on the left, , the alternation coding unit 11 converts 2 bits A as shown on the right side of FIG. 1(b),
Generate B. That is, if bit C is "0°", bit a of converted bit A is output as is, and if bit C is "1", bit A after conversion is "0"° and "1". .

is an alternating code that changes alternately every 12 frames. Similarly, if bit d is "0'", bit B after conversion is output as is, and if bit d is "1 pass", bit 13 after conversion is "O'° and "°1°". This is an alternating code that changes alternately every 12 frames.

The signaling bits A and B obtained by conversion in the alternating coding section 11 are inserted in the signal multiplexing section 12, with focus A being inserted into the 6th frame of the corresponding channel, and bit B being inserted into the 12th frame. Each signaling bit is multiplexed and input to the signal demultiplexer 13 of the other party's exchange via a transmission path.

The signal demultiplexer 13 separates the signaling bits of each channel, and the decoder 14 converts the alternating code into the original 4 bits.
Convert to bits a to d signals.

This decoding unit 14 corresponds to converting the code format on the right side of FIG. 1(b) to the signal format on the left side, and it is only necessary to compare and identify whether there is a change every 12 frames.

In this case, the signaling bits A and B are received every 12 frames (bit A in frame 6, bit B in frame 12), so if they are alternately encoded, they will change each time they are received.

The decoded signaling bits a to d are supplied to a control unit (not shown) of the local exchange and processed for control operations.

In this way, in the present invention, although a police box code is used on the transmission path, there is no need to handle the police box code in the exchange, and it can be handled as a level signal, so it is possible to process it using online software (the exchange can handle the police box signal). (no constant software processing required for processing).

[Example] A configuration diagram of an embodiment of the present invention is shown in FIG. 2(a).

20.25 in FIG. 2(a) is a switching section, 2126
22 is a control unit, and 22 is a transmission line ink face device W (
23 represents a transmission path, and 24 represents a transmission path interface device on the receiving side (represented by a transmission path IF).

The transmission lines IF22 and 24 in the figure are PCM24 transmission line interface devices, but the internal configuration only shows one for transmission in one direction (from left to right), and a configuration for the opposite direction is naturally provided, but it is not shown. It is.

Audio signals (digital) from the switching unit 20 of the exchange are input to the transmission line IF22, and four control signaling bits a to d representing the status of the subscriber are supplied from the control unit 21 to the transmission line IF22. transmission line l
In F22, the signaling bit converter 223 converts the 4-bit signaling bits into signaling bits for the transmission path including a 2-bit alternating code according to the conversion principle shown in FIG.
In step 2, the multiplexer 221 controls the insertion of the corresponding channel into a specific frame, and the multiplexer 221 inserts the audio channel into a predetermined bit position of the corresponding frame.

The 24-channel PCM signal multiplexed by the multiplexer 221 passes through the transmission path 23 and is received by the transmission path IF 24 of the destination exchange, and the audio signal is separated for each channel in the demultiplexer 241. In section 242, the signaling binos I-A and B are separated. The separated signaling bits are sent to the signaling bit decoding unit 2.
43, the signals are decoded and 4-bit signaling bits a-d are output and supplied to the control section 26, where they are used for switching control.

FIG. 2(b) shows a configuration diagram of the signaling bit converter.

27 and 28 in the figure are selection circuits, 222 and 221 are in Figure 2 (
It represents the signal insertion part and multiplex part similar to al.

The selection circuits 27 and 28 each have a selection control line 271281.
This selects one of the two inputs and outputs it. When the selection control signal is “0”, the input lines 272, 28
2 is selected and output as is to the output line 274.284, and if the selection control signal is 1'', the input line 273
, 283 are output as they are.

The input lines 273 and 283 have "alternating" signals (1
” and 0”) is input, and
In the selection circuit 27, the bit C is supplied as a selection control signal, and if the bit c is "1", an alternating code is output to the output line 274. Similarly, in the selection circuit 28, the bit D is supplied as a selection signal, When the bin) D is "1", an alternating code is output to the output line 284.

The signaling bit decoding unit 243 performs two signals every 12 frames.
It can be decoded by detecting the two bits using a synchronization signal and comparing and identifying whether their values change alternately.

[Effects of the Invention] According to the present invention, by using alternating codes in the transmission path, a large number of signaling bits can be transmitted with a small number of signaling bits for PCM24 channels, and a large number of signaling bits can be transmitted within an exchange. Since the bits can be treated as level signals as they are, they can be processed by online software.

[Brief explanation of the drawing]

Figure 1 (al is a basic block diagram of the present invention, Figure 1 (bl is a diagram showing the conversion format of signaling bits of the present invention, Figure 2 (al is a diagram showing the configuration of an embodiment of the present invention, Figure 2 (b ) is a configuration diagram and an explanatory diagram of an example of a signalling bit conversion section. In FIG. Figure 3 shows the conventional

Claims (1)

[Claims] 24 channels of audio data are transmitted and received in one frame, and m signaling bits corresponding to each channel are used m times in every fixed number of frames, using 1 bit in the audio data of the corresponding channel. In the signaling pattern control method of a PCM24 transmission line interface device that transmits data using a PCM24 transmission line interface device, p (p>m) signaling bits handled by an exchange are converted into a code including an alternation of m bits in an alternation assignment coding section (11), and the A signal multiplexer (12) inserts the converted m-bit code into the corresponding bit position of the voice code for each predetermined number of frames and transmits it, and on the receiving side, a signal multiplexer (13) extracts the converted m-bit code from the received signal. The m-bit signaling bits are separated and decoded (
A PCM characterized in that p signal bits are output to an exchange by decoding an alternating code in 14).
Signaling pattern control method for an X.24 transmission line interface device.