JPH0666752B2 - Signaling transmission method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a signaling transmission system for transmitting signaling related to digital transmission, and more particularly to a signaling transmission system when a digital trunk line of a telephone switching system is used.

[Prior Art] There are, for example, a bit steal method and an outslot method as a signaling transmission method using a digital relay line of a telephone exchange system.

FIG. 2 is a diagram showing an example of a transmission signal that performs signaling transmission by the bit steal method. As shown in Fig. 2 (a), PCM (pulsation) is included in the transmission rate of 1.544 Mb / s.
The coded audio signal is multiplexed in 24 channels. A frame bit F is added to the 24-channel audio signal. This frame bit F carries the information of the bit separation position of the channel separation and signaling. FIG. 2B shows the state of bit stealing by extracting the audio signal of FIG. 2A. That is, as for the bit position of signaling, as shown in FIG. 2B, the voice signal V is periodically replaced with the signaling S. The bit steal rate is 1/6 here.

FIG. 3 is a diagram showing an example of a transmission signal for signaling transmission by the outslot method. As shown in Fig. 3, 96 channels of PCM-encoded voice signals can be multiplexed in the transmission rate of 6.3 Mb / s. Here, channel 1 is used as a channel for multiplexing and transmitting only signaling. The audio signals used are channels 2 to 25. Further, the frame bit F described above is added to the signal composed of the signaling and the audio signal.

When the relay line that transmits signaling by the bit steal method as described above is relay-connected via the relay line that transmits the signal by the outslot method, that is, the bit steal section is in tandem across the outslot section. When connected, the bit steal bit positions of signaling in the bit steal intervals at both ends are arbitrary.

[Problems to be Solved by the Invention]

In the conventional signaling transmission method described above, the bit steal bit positions of signaling in the bit steal sections on both sides are independent. Therefore, the bit steal section is 2 links, and the bit steal rate in the case of 1 link may be 2/6, which is twice as high as 1/6. Therefore, there is a drawback that the quality of the audio signal is deteriorated.

An object of the present invention is to eliminate such drawbacks and to provide a signaling transmission system capable of transmitting a high-quality voice signal equivalent to one link even if the bit steal section has two links.

[Means for Solving the Problems]

According to the present invention, a first transmission line propagates a first transmission signal for signaling transmission by a bit steal method, and a second transmission line whose one end is relay-connected to the first transmission line, A second transmission signal for transmitting signaling by the outslot method propagates, and a third transmission path for relaying the other end of the second transmission path is used for transmitting the signaling by the bit steal method. In the signaling transmission method in which the third transmission signal propagates to perform signaling transmission, when the first transmission signal is converted into the second transmission signal, the signaling that is bit-stealed from the first transmission signal , A predetermined pattern is inserted in the bit position after the separation, and the transmission signal in which the predetermined pattern is inserted and the separated signaling are outslotted. When the second transmission signal, which is formed by multiplexing according to the G.T.O.t.t. method, is sent out to the second transmission line and the second transmission signal is converted into the third transmission signal, the second transmission signal is converted from the second transmission signal. Signaling is separated, a predetermined pattern is detected, and the third transmission signal, in which the separated signaling is carried by the bit steal method, is sent to the third transmission line at the bit position on which the predetermined pattern is carried. It is characterized by that.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an example of a signaling transmission system for implementing the present invention. In FIG. 1, a multiplexer 10 performs signaling conversion from a bit steal transmission line 1 to an outslot transmission line 2. Also, the multiplex conversion device 20 performs signaling conversion from the outslot transmission line 2 to the bit steal transmission line 3. It should be noted that FIG. 1 shows only signals transmitted from the multiplex converter 10 to the multiplex converter 20.

The transmission signal transmitted through the bit steal transmission line 1 is a signal as shown in FIG. This transmission signal is input to the multiplex conversion device 10 and separated by the signaling separation circuit 11 into a voice signal a and a signaling b. In the voice signal a from which the signaling b has been separated, the pattern insertion circuit 12 inserts a predetermined pattern, for example, "1" or "0" alternating pattern, in the bit position where the signaling was carried. Then, the voice signal c in which the alternating pattern of “1” and “0” is inserted and the signaling b are input to the multiplexing circuit 13. The multiplexing circuit 13 sends a transmission signal obtained by multiplexing the signaling b and the voice signal c as shown in FIG. 3 to the outslot transmission line 2.

The transmission signal transmitted through the outslot transmission line 2 is input to the multiplex conversion device 20 and separated by the separation circuit 21 into the signaling d and the audio signal e. The voice signal e is input to the pattern detection circuit 22. And here “1”,
A “0” alternating pattern is detected, and bit position information f indicating the bit position of the pattern is output to the signaling multiplexing circuit 23. At the same time, the signaling multiplexing circuit 23 receives the signaling d and the audio signal e. The signaling multiplexing circuit 23 uses the bit position information f from the pattern detection circuit 22 to multiplex the signaling d by bit steal at the same bit position as that used in the bit steal transmission line 1. As a result, the bit multiplexing circuit 23 sends the transmission signal shown in FIG. 2 to the bit steal transmission line 3.

In this way, the bit position of signaling of the transmission signal transmitted through the bit steal transmission line 3 can be made the same as the bit position of signaling of the transmission signal transmitted through the bit steal transmission line 1.

For the transmission of a signal from the multiplex converter 20 to the multiplex converter 10, the multiplex converter 20 includes a pattern insertion circuit, a signaling separation circuit, and a multiplex circuit, and the multiplex conversion device 10 has a pattern detection circuit, a separation circuit, and a signaling circuit. This becomes possible by including a multiple circuit.

〔The invention's effect〕

As described above, according to the present invention, a predetermined pattern is inserted into the bit after releasing the bit steal, and the bit is transmitted through the outslot transmission line. Then, when the signaling is multiplexed again by bit stealing, the signaling can be multiplexed by bit stealing to the original bit stealing bit position by detecting a predetermined pattern, so that the bit stealing section has two links. Even so, there is an effect that a high-quality transmission signal equivalent to one link can be transmitted.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a signaling transmission system for carrying out the present invention, FIG. 2 is a diagram showing an example of a transmission signal for signaling transmission by a bit steal method, and FIG. 3 is an outslot. It is a figure which shows an example of the transmission signal which performs signaling transmission by a system. 1,3 …… Bit steal transmission line 2 …… Outslot transmission line 10, 20 …… Multiplex converter 11 …… Signaling separation circuit 12 …… Pattern insertion circuit 13 …… Multiplex circuit 21 …… Separation circuit 22 …… Pattern Detection circuit 23 ... Signaling multiplexing circuit

Claims (1)

[Claims] 1. A first transmission signal for transmitting signaling by a bit steal method propagates through the first transmission path,
A second transmission signal for transmitting signaling by an outslot method propagates through a second transmission line, one end of which is relay-connected to the first transmission line, and the other end of the second transmission line is relayed. In a signaling transmission method in which a third transmission signal for transmitting signaling by a bit steal method propagates through a connected third transmission path to perform signaling transmission, the first transmission signal to the second transmission signal are transmitted. When converting to a transmission signal of, the bit-stealed signaling is separated from the first transmission signal, a predetermined pattern is inserted at the bit position after the separation, and the transmission signal in which the predetermined pattern is inserted and this The second transmission signal obtained by multiplexing the separated signaling by the outslot method is sent out to the second transmission path, and the second transmission signal is forwarded from the second transmission signal. When converting to the third transmission signal, the signaling is separated from the second transmission signal to detect a predetermined pattern, and the separated signaling is placed by the bit steal method at the bit position on which the predetermined pattern is placed. A signaling transmission system characterized in that the third transmission signal comprising the above is transmitted to the third transmission line.