JPS60210041A - Meeting line system of time division multi-connection system - Google Patents

Abstract

PURPOSE:To attain the effective use of a meeting line by occupying one of time slots for general call when necessary for the meeting line and therefore eliminating the disturbance to other talking circuits without using any special signal system. CONSTITUTION:Plural slave stations B are provided to a master station A to form a time division multi-connection system. Then call line control circuits 4-6 are connected to the station 1 via general call lines 1-3, and a switch network 7 and a center control part 11 are connected to circuits 4-6 to perform the 2-/4- wire conversion and level conversion. While a meeting telephone 14 is connected to the network 7 via a meeting line 15, and the outputs of time slot control circuits 8-10 and a time slot control circuit 13 for control connected to the part 11 are supplied to a radio unit 16. Thus a talking circuit is formed to stations B by means of a time slot. The output of a slave station control part 18 of a slave device B is supplied to a changeover switch 19 and allocated to a general talking circuit 20 and a meeting line 21 by the switch 19. Then one of slots is occupied by the circuit 21 when necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to Which the Invention Pertains] The present invention relates to a meeting line used for time division multiple access (TDMA) maintenance.

[Description of prior art]

In the time division multiple access system, the meeting line may be transmitted in the multiplexed signal, or a separate line dedicated to the meeting line may be provided. When transmitting in a multiplexed signal,
It is transmitted using a special signal system that is different from general telephone lines. However, transmitting a meeting line in a multiplexed signal reduces the number of general communication lines, and the special signaling system also causes interference noise.

Further, if a meeting line is provided separately from the multiplex signal, there is an advantage that it can be used even when the multiplex line is damaged, but the equipment becomes larger.

[Purpose of the invention]

The present invention is a system for transmitting a meeting line in a multiplexed signal, in which a predetermined line among the general call lines is separated from the general call line only when the meeting line is needed, and the signal system is exactly the same as that for general calls. The purpose is to provide a system that can be used as a meeting line.

[Features of the Invention] According to the present invention, in a time division multiple access system, the master station has a means for blocking the general communication line and occupying a predetermined communication time slot as necessary for a meeting line. It also has a means for indicating, using the control time slot, whether or not the above-mentioned call time slot is occupied and usable as a meeting line. On the other hand, the slave station receives the signal from the control time slot and has means for determining whether the meeting line is available or not, and has the means to switch the communication line to the meeting line if necessary.

Owing to the above features, a line for general calls and a meeting line can be shared without using any special signaling system, and therefore an economical meeting line can be constructed.

That is, it includes one master station and a plurality of slave stations connected to the master station via wireless lines, and the master station has a large number of communication line control circuits each connected to a large number of general communication lines, comprising a plurality of time slot control circuits connected to the wireless line, a switch network interconnecting the time slot/node control circuit and the call line control circuit, and a central control unit controlling the switch network, In a time division multiple access system, the slave station is equipped with a slave station control unit that detects a time slot assigned to the slave station in the wireless line and inputs and outputs information to the time slot. for,
A meeting line control unit to which a meeting line is connected and connected to the switch network, and means for transmitting and receiving a meeting line control signal in a control time slot of the wireless line according to a command from the central control unit, the central control unit teeth,
comprising a control means for connecting the meeting line control unit to one of the time slot control circuits, the slave station control unit of the slave station including means for identifying the meeting line control signal of the control time slot node; The above slave stations include
The present invention is characterized in that it includes a switch that switches and connects the input/output line of the slave station control section to the meeting line based on the output of the identifying means.

[Explanation based on examples]

FIG. 1 is a conceptual diagram of a time division multiple access system.

FIG. 2 is a block configuration diagram according to an embodiment of the present invention. In FIGS. 1 and 2, A is a master station, B is a slave station, and they are scattered around the master station A.

In the master station A, the n general communication lines 1.2.3 are each connected to a communication line control circuit 4.5.6 and undergo two-wire and four-wire conversion and level conversion. One human output line passes through switch W47, and time slot control circuit 8.9.10
It is connected to the. The other $ input/output line is connected to receive a control signal from the central control unit 11. Further, the input terminal of the central control unit 11 is connected to the switch 12, and the output terminal is connected to the above-mentioned communication line control circuits-4, 5, 6, and the switch! f147, the time slot control circuit 8.9.10, and the control time slot control circuit 13, respectively.

Here, the feature of the present invention is that the meeting communication live line 14
passes through the meeting line control circuit 15 and is connected to the switch network 7. Time slot control circuit 8
．． The outputs of 9.10 and 13 are connected as radio wave signals to the slave station via the radio 13 using one time slot to form a speech line. At the slave station B, the radio 17 passes through the slave station control unit 18 and is connected to the general call line 2 by the switch 19.
0 and the meeting line 21. The switch 19 is connected to control the output of the slave station control section 18 and the signal from the switch 22 through a gate 23.

Next, the operation of the embodiment device of the present invention will be explained.
If you do not use the meeting line, use the general live line 1.2.3.
The one used for telephone calls is the telephone line control circuit 4.
．． 5.6, it is connected to one of the time slot control circuits 8.9.10 via the switch network 7. The time slot control circuit is determined by the control of the central control section.

Then, using one time slot, a communication line is formed with the slave station via the radio 16 as a radio wave signal.

Similarly, in the slave station, among the data strings transmitted and received via the radio device 17, the time slot number for communication determined by the central control unit 11 of the master station is used for control transmitted from the control time slot control circuit 13. The slave station controller 1 transmits data from among the designated time slots to the slave station controller 1, and sends and receives data in the designated time slot to form a communication line with the master station.

On the other hand, when a meeting line is used, a channel normally used as a general call line is allocated for the meeting line. That is, when the switch 12 is pressed at the master station, the central control unit 11 controls the time slot control circuit 8.
9. Connect the back one (i) of 10 to the meeting line control circuit 15 via the switch network 7. It also informs the control time slot control line 13 that the meeting line is available for use at time slot i, and transmits this to the slave station using the control time slot. If slave station B is not in use in this state, the gate 23 opens and the slave station control unit 18
A display is sent to the operator. When the switch 22 is pressed, the switch 19 is activated, and the telephone line to the slave station control section 18 is connected to the meeting line 21. Further, when the slave station is talking, the gate 23 is closed, and even if the switch 22 is pressed, the call line is connected to the general call line 20 side.

If all of the time slot control circuits 8.9.10 are used and the meeting line control circuit 15 cannot be connected, it is indicated that the meeting line time slot is prohibited from use.

In this way, even if the switch 12 on the master station side is pressed, if all of the time slot control circuits 8.9.10 are used for general calls, the state is "waiting" and a call line for the meeting line is not formed. However, if any one of the time slot control circuits 8.9.10 is open, the meeting line becomes available and the time slot is blocked for general calls until the switch 12 is released.

On the other hand, when using the meeting line from the slave station side, when the switch 22 is pressed, the slave station control section 18 sends a command to the master station via the radio 811 using a control time slot signal. The master station detects the control time slot 13 and sends out a display from the central control unit 11. As a result, when the switch 12 is operated, the switch is activated to form a meeting line! 1li17.

In general, a sufficient number of time slot control circuits 8.9.10c can be prepared so that call processing will not be affected even if one of the time slot control circuits is blocked for a meeting line except during the busiest call times.

Also, during general calls, the number of call line control circuits 4.5.6 and the number of slave stations correspond one to one, and if they have the same ID code but different codes, a call line will not be formed, but the number of call line control circuits 4.5.6 and the number of slave stations will not be formed. In this case, all the slave stations whose switch 22 was pressed can use the time slot of the meeting line.

〔Effect of the invention〕

As described above, according to the present invention, by occupying one of the time slots for general calls for a meeting line as necessary, there is no waste in the line.

Furthermore, since no special signaling system is used, there is no interference with other communication lines. In this way, an economical meeting line can be obtained by sharing the line for general calls.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of a time division multiple access system. FIG. 2 is a block diagram of an embodiment of the present invention. A... Master station, B1... One of a plurality of slave stations, 1,2゜3... General call line, 4.5.6... Call line control circuit, 7... Switch network , 8, 9.10... Time slot control circuit, If... Central control unit, 12... Meeting line instruction switch, 13... Time slot control circuit for control, 14... Meeting line, 15 ...Meeting line control circuit, 16.17... Radio device, 18... Slave station control unit, 19... Changeover switch, 20... General call line, 21... Meeting line, 22. ...Meeting line display switch, 23...gate. Patent Applicant NEC Corporation Agent Patent Attorney Nao Takashi Ide 1 Figure 1

Claims (1)

[Claims] (11) Includes one master station and a plurality of slave stations connected to the master station via wireless lines, and the master station has a large number of slave stations each connected to a large number of general communication lines. A telephone line control circuit, a plurality of time slot control circuits connected to the wireless line, a switch network interconnecting the time slot control circuit and the telephone line control circuit, and a central control unit controlling the switch network. and a time division multiple access system, wherein the slave station is equipped with a slave station control unit that detects a time slot assigned to the slave station in the wireless line and inputs and outputs information to the time slot. In this case, the master station includes a meeting line control unit to which a meeting line is connected and connected to the switch network, and means for transmitting and receiving a meeting line control signal to the control time slot of the radio line according to instructions from the central control unit. The central control unit includes control means for connecting the meeting line control unit to one of the time slot control circuits, and the slave station control unit of the slave station connects the meeting line control unit to one of the time slot control circuits. The time-division multiplexing device includes means for identifying a control signal, and the slave station is provided with a switch that switches and connects the input/output line of the slave station control section to a meeting line based on the output of the identifying means. Connection method: Meeting line method.