JP3305691B2 - Time division multiplexer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a layer 1 protocol defined by a dedicated line basic user / network interface, and is connected to a subscriber interface (hereinafter, referred to as an LI point) of a communication line that performs limited power supply. The present invention relates to a time division multiplexer.

[0002]

2. Description of the Related Art A time division multiplexer (TDM)
ion Multipulexer)) is a single line by switching and transmitting a plurality of data and digitized voice at predetermined time intervals (time slots) corresponding to a high-speed digital line network such as a satellite line or ISDN. Performs communication on multiple channels.

FIG. 3 is a diagram showing an example of a frame configuration of a conventional multiplexing system (2.4 kbps signal frame), and FIG. 4 is a block diagram showing an example of a configuration of a conventional time-division multiplexing device. is there. The time division multiplexing device 4
-IF transceiver 41, serial / parallel conversion circuits 42, 4
3. Multi-frame synchronization timing extraction circuit 44, synchronization signal transmission circuit 45, separation / multiplexing means 46 for separating and multiplexing signals during transmission, transcoder (code compressor) 47, codec (speech encoder) ) 48 and a digital terminal transmitting / receiving means 49, a line terminating device 20 for performing LI point processing and the like, a power supply device 61 for receiving power supply from a commercial power supply, and a power supply unit 60 including a storage battery 62.

As an example of a conventional time-division multiplexing apparatus, a multiplexing method using a 2.4-system synchronous data signal in TTC standard JJ-20.31 can be used to multiplex signals of different speeds. As shown in FIG. 3, a multi-frame configuration using frame synchronization bits is adopted. Fifty 20 multi-frame patterns are applied (in FIG. 3, the symbol F is a frame synchronization bit, D1 to D6 are information bits, S is a status bit, M
F is a multi-frame, A is a path alarm bit ("1" when normal, "0" when abnormal), and CH1 to CH20 indicate channel numbers).

In this synchronization system, it is necessary to establish not only the frame synchronization with the network by the transceiver but also the multi-frame synchronization with the opposing device by decoding the multi-frame pattern transmitted from the opposing device.

In order to realize multi-frame synchronization, FIG.
In the example of FIG. 1, first, S-
The information channel (B1 in FIG. 4) output from the IF transceiver 41 is serial-to-parallel converted so that the multi-frame pattern can be decoded, and then the timing at which the first bit of the parallel data matches the multi-frame pattern Is a multi-frame synchronization bit, and based on this, SI
It is necessary to provide the F transceiver 41, the demultiplexer / multiplexer 46, the transcoder 47 and the codec 48 with transmission / reception timing.

For this purpose, the line termination device 50 and the S-
In addition to the IF transceiver 41, the demultiplexing / multiplexing means 46, the transcoder 47 and the codec 48, serial / parallel conversion circuits 42 and 43, a multi-frame synchronization timing extraction circuit 44 and a synchronization signal transmission circuit 45 are required. There is a problem that the power consumption of the line terminating device 50 and the main body 40 increases, and the station power supply with a small capacity cannot cover the power consumption.

For this reason, in the conventional time-division multiplexing device 4, the power consumed by the line terminating device 20 and the main body 40 is generated and supplied by the commercial power supply device 61 to supply the power. Further, with this configuration, the power supply unit 60 is configured to extract power from the storage battery 62 and supply the power consumed by each functional block at the time of a power failure so that power can be supplied during the power failure.

[0009]

In the conventional time-division multiplexing apparatus, the above-described countermeasures against a power failure caused by a storage battery have a problem that when using a primary battery, it is necessary to replace the battery with a new one every time the battery is discharged. However, there is a problem that when a secondary battery is used, charging by a charging circuit is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a time division multiplexing apparatus which operates with power supplied from a station without using an external power supply such as a commercial power supply.

[0011]

According to the present invention, there is provided a time-division multiplexing apparatus which is connected to a communication line which performs a limited power supply using a layer 1 protocol.
The power supply required by each module that composes the device with limited power supply with a small amount of power from the station by simplifying the circuit configuration and adopting a simplified synchronization system and multiplexing system. Is generated based on the station power supplied to the LI point and supplied to each module.

More specifically, the time-division multiplexing apparatus of the first invention is connected to a subscriber interface of a communication line that performs limited power supply via an LI point layer 1 processing unit and a UNI point layer 1 master processing unit. Time-division multiplexing device, comprising: a UNI connected to a UNI point layer 1 master processing means.
Point layer 1 slave processing means and this UNI point layer 1
The demultiplexing / multiplexing means connected to the slave processing means, the code compression means connected to the demultiplexing / multiplexing means, the voice coding means connected to the code compression means, and the UNI point layer 1 slave processing means Timing signal generating means for generating a timing signal based on a network synchronization clock to be applied to code compression and transmitting the signal by a demultiplexing / multiplexing means.
Signal separation and signal multiplexing processing at the time are 8 kbps synchronization data.
Data signal multiplexing.

[0013]

According to a second aspect of the present invention, in the time division multiplexing apparatus according to the first aspect of the present invention, the power supplied from the communication line is converted and the LI point layer 1 processing means, the UNI point layer 1 master processing means, the UNI point An internal power supply unit for supplying a layer 1 slave processing unit, a code compression unit, a voice encoding unit, and a timing signal output unit is provided.

[0015]

FIG. 1 is a block diagram showing the configuration of an embodiment of a time division multiplexing device according to the present invention. The time division multiplexing device 1 includes an S-IF transceiver 11 and a signal separation device during transmission. And a demultiplexer / multiplexer 12 for performing multiplexing processing, a transcoder (code compressor) 13, a codec (speech coder) 14, and a general-purpose logic circuit 15
And a line terminating device 20 composed of LI point processing and the like.
A DC converter (internal power supply means) 30 is provided.

The line terminating device 20 performs LI point layer processing and UNI point layer 1 master processing, and the transceiver 11 functions as a UNI point layer 1 slave processing means. The symbol SYNC is an output timing signal generated by the general-purpose logic circuit 15, and the symbols Vin (+),
Vin (-) is an input voltage (limit voltage) to the DC-DC converter 30, and symbol VDD is the DC-DC converter 30.
The output voltage from is shown. The UNI point means a user network interface.

The time-division multiplexing apparatus 1 generates an 8 kbps signal system synchronous data signal (TTC standard JJ2) as shown in FIG.
The multiplexing method of 0.31) is used. In this multiplexing method, since the accommodation position of the channel is determined for each speed, it is not necessary to adopt a multi-frame configuration using frame synchronization bits.

That is, in the synchronization system of the 8 kbps signal system, only the network synchronization clock generated by the transceiver 11 is used. For this reason, the multi-frame pattern transmitted from the opposing device side as in the conventional time-division multiplexing device 4 of FIG.
There is no need to provide transmission / reception timing for 46 to 48.

By adopting the 8 kbps signal-based synchronization system as described above, for example, from the conventional time-division multiplexing device 4, the serial-to-parallel conversion circuits 42 and 43, the multi-frame synchronization timing extraction circuit 44, and the synchronization signal transmission A time-division multiplexing circuit without the circuit 45, that is, a time-division multiplexing device 1 as shown in FIG. 1 can be configured (in FIG. 1, the network synchronization clock generated by the transceiver 11 is a general-purpose logic circuit). 15 as a transcoder (code compressor) 13 as an output timing signal SYNC.
Given to you).

The time-division multiplexing apparatus 1 has a configuration in which serial-to-parallel conversion circuits 42 and 43, a multi-frame synchronization timing extraction circuit 44 and a synchronization signal transmission circuit 45 are deleted from the configuration of the conventional time-division multiplexing apparatus 4. The main body 1
The processing within 0 is simplified, and as a result, the power consumption of the entire time-division multiplexing device 1 can be reduced.

In the embodiment, the time-division multiplexing apparatus 1 uses a DC limited voltage (DC constant voltage) V supplied from a communication line at an LI point.
In (+) and Vin (-), it is possible to receive about 1 W (watt) of power (station-supplied power), and the DC-DC converter 30 supplies the supplied DC limited voltages Vin (+) and V
A power supply that can be used directly by the line termination device 20 and the main body 10 of the time-division multiplexing device 1 is created from in (−), and the power supply is generated by the line termination device 20, the S-IF transceiver 11, and the transcoder (code compressor) 13. , A codec (speech encoder) 14 and a general-purpose logic circuit 15. The demultiplexing / multiplexing means 12 performs signal demultiplexing and multiplexing processing at the time of transmission based on the multiplexing method of the 8 kbps signal system synchronous data signal (TTC standard JJ20.31) as shown in FIG.

As described above, since the configuration of the main body module of the time division multiplexing apparatus is simplified, sufficient power can be supplied to all modules within the limited power supply, and power supply from an external power supply is required even during a power failure. lost.

In the above embodiment, the DC-DC converter 30 supplies the supplied DC constant voltages Vin (+), Vin (+).
(-) Is input to create a power supply that can be directly used by the line termination device 20 and the main body 10 of the time division multiplexing device 1, but the present invention is not limited to this. That is, DC-DC
The converter 30 may be configured so that a constant current is input to create a power supply that can be directly used by the line termination device 20 and the main body 10 of the time division multiplexing device 1. As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, It cannot be overemphasized that various deformation | transformation implementation is possible.

[0024]

As described above, according to the present invention,
It is possible to provide a time-division multiplexing device that operates only with internal power supply means using power supplied from a communication line without using an external power supply such as a commercial power supply provided in a conventional time-division multiplexing device. . Further, the need for an external power supply such as a commercial power supply has been eliminated, so that it is possible to take a power outage countermeasure without a backup by a storage battery or the like.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a time division multiplexing device of the present invention.

FIG. 2 shows an example of a frame configuration of a multiplexing method applied to the time division multiplexing device of the present invention (8 kbps signal frame).
FIG.

FIG. 3 shows an example of a conventional multiplexing frame configuration (2.
FIG. 4 is a diagram illustrating a 4 kbps signal frame).

FIG. 4 is a block diagram showing a configuration of an example of a conventional time-division multiplexing device.

[Description of Code] 1,4 Time-division multiplexing device 11 S-IF transceiver (UNI point layer 1 processing means) 12 Demultiplexing / multiplexing means 13 Transcoder (code compressor) 14 Codec (voice coder) 15 General purpose Logic circuit (timing signal generation means) 20 Line termination device (LI point layer 1 processing means, UNI
Point layer 1 master processing means and transformer (transformer)) 30 DC-DC converter (internal power supply means)

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H04J 3/00 H04M 11/00 303 H04M 19/00 JICST file (JOIS)

Claims (2)

(57) [Claims] 1. A time-division multiplexing apparatus connected to a subscriber interface of a communication line for performing a limited power supply via an LI point layer 1 processing unit and a UNI point layer 1 master processing unit, wherein the UNI point layer 1 UNI connected to master processing means
Point layer 1 slave processing means, demultiplexing / multiplexing means connected to the UNI point layer 1 slave processing means, code compression means connected to the demultiplexing / multiplexing means, and audio coding connected to the code compression means Means for generating a timing signal based on a network synchronization clock generated by the UNI point layer 1 slave processing means and applying the timing signal to the code compression, and a signal for transmission by the demultiplexing / multiplexing means. Separation
And the signal multiplexing process multiplexes 8 kbps system synchronous data signals.
Time-division multiplexing device characterized by performing the multiplexing method
Place. 2. The power supplied from the communication line is converted.
The LI point layer 1 processing means and the UNI point layer 1
Star processing means, UNI point layer 1 slave processing means,
Signal compression means, audio coding means and timing signal output means
Internal power supply means for supplying power to the stage.
The time-division multiplexing device according to claim 1.