JPH0766761A - Satellite communication system - Google Patents

Abstract

PURPOSE:To attain communication among plural satellite communication earth stations which can execute broadcast communication from a master station to two or more slave stations by simple equipment constitution. CONSTITUTION:When all communication signal transmitting receiving devices 108 in a certain slave station 130-1 to be object of broadcast communication execute communication among satellite communication earth stations and a control station 101 transmits a communication stop command 113 to a communication stop command transmitter 106 at the same frequency as the communication signal receiving frequency of one device 108 in the slave station 103-1, the one device 108 in the slave station 103-1 stops communication, turns its state to a common signal transmitting/receiving state and sets up its communication signal receiving frequency to frequency for broadcast communication which is determined by the control station 101 to execute broadcast communication using a communication signal 112.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for controlling a common signal of a satellite communication line. The present invention uses a request allocation satellite communication system in which a plurality of satellite communication earth stations share communication by sharing two or more transmission paths according to an instruction from a control station, and a specific satellite communication earth station to two or more other satellites. The present invention relates to a satellite communication system in which the equipment of each earth station for performing broadcast communication to a communication earth station has a simple structure and cost can be reduced.

[0002]

2. Description of the Related Art Generally, in a request assignment satellite communication system in which a plurality of satellite communication earth stations of three or more stations communicate by sharing instructions of two or more transmission channels according to an instruction from a control station, common transmission channel resources are used. A common signal transmission line for transmitting the transmission line allocation information between the control station that manages and allocates the transmission line according to the request and each earth station is required.

In such a demand assignment satellite communication system, as shown in FIGS. 2 and 4, each earth station normally receives a common signal 18 sent from the control station 1 via a communication satellite 19.
When the common signal processing unit 23 receives the communication signal transmitting / receiving devices 9 and 13 through the demodulation unit 21 and the communication signal frequency is specified by the common signal 18 from the control station 1, the common signal processing unit 23 performs the communication signal processing. By transmitting the frequency control signal 25 to set the communication signal frequency to the unit 24 and transmitting the information notifying that the control is performed to the control station 1 through the modulator 22, the communication signal terminal device 8
Was communicating.

Further, conventionally, when performing broadcast communication from the master station 2 to a plurality of slave stations 3-1 to 3-n of two or more stations, a common signal 15 for broadcast communication from the master station 2 is used for each broadcast. Slave stations 3-1 to 3
The common signal transmitter / receiver 14 for broadcast communication of -n sets the communication signal reception frequency of one communication signal transmitter / receiver 13 to the frequency for broadcast communication, and uses the communication signal 17 of the set frequency to synchronize I was doing a newsletter. That is, when all the communication signal transmission / reception devices 13 in a certain slave station 3-1 are communicating with the satellite communication earth station, the master station 2 is required to perform the broadcast communication. Using the common signal 15 for broadcast communication, the common signal transmitter / receiver 14 for broadcast communication of the slave station 3-1 is used.
The communication between the satellite communication earth stations of one communication signal transmitting / receiving device 13 in the slave station 3-1 is stopped by the forced communication disconnection signal 20 via the mobile station 3-1 and the reception frequency for the communication signal of the slave station 3-1 is broadcast. Therefore, the broadcast signal is transmitted using the communication signal 17.

As another conventional example, Japanese Patent Laid-Open No. 58-206259 discloses a technique capable of interrupting another priority communication during broadcast communication. A method of preferentially interrupting information communication has not been proposed yet.

[0006]

As described above, according to the prior art, in order to carry out the broadcast communication from the master station to a plurality of slave stations of two or more stations, the satellites are transmitted to the communication signal transmitting / receiving devices in all the slave stations. It is necessary to provide a common signal transmission / reception device for broadcast communication for performing communication between communication earth stations, which requires a large amount of cost for equipment.

The present invention has been made in order to solve such a problem, and has a simple structure of a master station and a slave station,
It is an object of the present invention to provide a satellite communication line common communication control system capable of reducing equipment costs.

[0008]

A first aspect of the present invention controls a master station and a plurality of slave stations that communicate via a communication satellite, and transmission / reception of information between the master station and the plurality of slave stations. In the satellite communication system provided with a control station, the means for transmitting a communication stop command to the control station at the frequency received by the slave station which is the target of the generated broadcast communication, and the communication stop command Then, a means for designating the frequency of the broadcast communication by a common signal received by the slave station is provided.

The control station includes means for transmitting and receiving control signals to and from the master station and the slave station via the communication satellite, and the control station is installed in one of the master station and the slave station. Is desirable.

That is, the control station includes a control device, a common signal transmission / reception device for transmitting / receiving a common signal, and a radio frequency conversion unit for converting a radio frequency of the common signal and transmitting it via an antenna. A plurality of communication signal terminal devices, a communication signal transmission / reception device that is connected to the communication signal terminal device and transmits / receives communication signals, and a radio frequency conversion unit that converts radio frequencies of communication signals and transmits / receives them via an antenna Each of the slave stations, a plurality of communication signal terminal device, and a plurality of communication signal transmitting and receiving device individually connected to each of the communication signal terminal device for transmitting and receiving communication signals, and transmitted and received via the antenna In a satellite communication system including a communication control means configured by an outdoor device and a multicarrier control device for controlling the communication signal, Common signal control means for instructing wave number allocation control, broadcast communication request signal receiving means for receiving a broadcast communication request signal transmitted from the common signal transmission / reception device, and a communication stop command for which communication signal frequency A communication stop command transmitting frequency control means for controlling whether to transmit, and a broadcast communication request signal receiving means for receiving a broadcast communication request signal from the common signal transmitting / receiving apparatus to the control station; A communication stop command transmitting device including a communication stop command frequency control signal receiving means for receiving a communication stop command frequency control signal from the communication stop command transmitting means and a communication stop command transmitting means for transmitting a communication stop command in the communication signal frequency band. It is characterized by

The common signal transmission / reception device receives common signal transmission means for transmitting a common signal received from the control device to the master station and the slave station, and a common signal of response from the master station and the slave station. Common signal receiving means, broadcast communication request signal identifying means for identifying whether or not the common signal received from the master station is a broadcast communication request signal, and broadcast communication for sending out the broadcast communication request signal to the control device. The master station communication signal transmitting / receiving device includes a request signal transmitting means, a common signal receiving means for receiving a common signal from the control station, a common signal processing means for processing the received common signal, and the common signal processing means. Common signal transmitting means for transmitting a response of the common signal processed by the signal processing means to the control station, wherein the communication signal transmitting / receiving device of the slave station has a frequency specified by the communication signal transmitting / receiving device of the master station. Communication signal receiving means for receiving communication signals of other master stations or slave stations, communication signal processing means for processing the received communication signals, and communication signals processed by the communication signal processing means for other master stations or slave stations It is desirable to include a communication signal transmitting means for transmitting to the.

A second aspect of the present invention is that, when a control station requests broadcast communication, a communication stop command is sent from the control station at the reception frequency used by the slave station which is the target of the broadcast communication. , The reception frequency of the slave station is automatically switched to the reception frequency of the common signal, and then the reception frequency of the slave station is changed by specifying the frequency of the broadcast communication by the common signal, and the broadcast communication is performed. It is characterized in that the request source of (1) is sent a broadcast communication at the changed frequency.

[0013]

[Operation] When all the communication signal transmitting / receiving devices in the slave station which is the target of the broadcast communication are communicating with the satellite communication earth station but not receiving the broadcast communication, the control station issues a communication stop command. When the transmitter sends a communication stop command to one of the slave station's communication signal transmitters / receivers at the same frequency as the communication signal reception frequency, the communication signal transmitter / receiver suspends communication and transmits / receives the common signal. Then, the communication signal reception frequency is set to the frequency for broadcast communication determined by the control station by the received common signal, and the broadcast communication is performed.

As described above, by providing the communication stop command transmitter for transmitting the communication stop command to the control station so that the control station can control the communication stop,
The common signal transmitting device for broadcast communication provided in each slave station becomes unnecessary, and the facility cost can be significantly reduced. Further, it becomes possible to set the state in which the normal communication can be stopped and the common signal can be transmitted / received and the broadcast communication can be performed in a short time.

[0015]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a block diagram showing the concept of a broadcast communication network in an embodiment of the present invention, and FIG. 2 is a block diagram showing the configuration of the main part of a communication signal transmitting / receiving apparatus in an embodiment of the present invention and a conventional example.

In the embodiment of the present invention, a master station 102 and a plurality of slave stations 103-1 to 10-1, which communicate with each other via a communication satellite 19, are provided.
03-n, a master station 102 and a plurality of slave stations 103-1 to 103-n.
Control station 101 for controlling transmission / reception of information between 103-n, and further, in the control station 101, the frequencies received by the slave stations 103-1 to 103-n which are the targets of the generated broadcast communication. Means for transmitting a communication stop command with the slave station 103-1 to 103-
-N means for designating the frequency of the broadcast communication by a common signal and a control signal via the communication satellite 19 to the master station 10
2 and slave stations 103-1 to 103-n, and means for transmitting and receiving, and the master station 102 or the slave stations 103-1 to 103-.
It is attached to one of the n.

That is, the control device 101 is connected to the control station 101.
4 and a common signal transmitting / receiving apparatus 10 for transmitting / receiving a common signal
5 and a radio frequency conversion unit 6 that converts the radio frequency of the common signal and transmits it via the antenna 7.
In addition, a plurality of communication signal terminal devices 8 and a communication signal transmitting / receiving device 108 that is connected to the communication signal terminal device 8 and transmits / receives a communication signal, and transmits / receives via the antenna 7 by converting the radio frequency of the communication signal. A plurality of communication signal terminal devices 8 are included in each of the slave stations 103-1 to 103-n including the radio frequency conversion unit 6, and are individually connected to each of the communication signal terminal devices 8 to transmit and receive communication signals. A plurality of communication signal transmission / reception devices 108 to perform, and a communication control unit configured by an outdoor device 11 and a multicarrier control device 12 for controlling the communication signals transmitted / received via the antenna 7, and as a feature of the present invention, A common signal control means for instructing the control device 104 to control allocation of frequencies for communication signals, and a broadcast communication request signal transmitted from the common signal transmission / reception device 105. It includes a broadcast request signal receiving means for signal, and a communication stop command sending a frequency control means for controlling or transmit communication discontinuation command to which the communication signal frequency, the control station 101, a common signal transmission and reception apparatus 105
A broadcast communication request signal receiving means for receiving a broadcast communication request signal from the controller, a communication stop command frequency control signal receiving means for receiving a communication stop command frequency control signal from the control device 104, and a communication signal frequency band. A communication stop command transmitting device 106 including a communication stop command transmitting means for transmitting a communication stop command is provided.

Further, common signal transmitting / receiving apparatus 105 has common signal transmitting means for transmitting the common signal received from control apparatus 104 to master station 102 and slave stations 103-1 to 103-n, and master station 102 and slave station 103. Common signal receiving means for receiving a common signal of response from -1 to 103-n, and the master station 1
Broadcast request signal identifying means for identifying whether or not the common signal received from 02 is a broadcast request signal, and the control device 104.
A broadcast communication request signal transmitting means for transmitting a broadcast communication request signal to the master station 102.
Is a common signal receiving means for receiving a common signal from the control station 101, a common signal processing means for processing the received common signal, and a common signal response processed by the common signal processing means for transmission to the control station 101. The communication signal transmitting / receiving apparatus 108 of each of the slave stations 103-1 to 103-n includes a common signal transmitting unit for transmitting the signal to the other master station or the slave station at the frequency designated by the communication signal transmitting / receiving apparatus 107 of the master station 102. Communication signal receiving means for receiving a communication signal, communication signal processing means for processing the received communication signal, and communication signal transmitting means for transmitting the communication signal processed by the communication signal processing means to another master station or slave station. including.

Next, the operation of the embodiment of the present invention thus constructed will be described. FIG. 3 is a flow chart showing the operation flow of the control device of the control station in the embodiment of the present invention.

According to the present invention, when the control station 101 requests a broadcast communication, the slave station 103-which becomes the target of the broadcast communication
1 to 103-n transmits a communication stop command from the control station 101 at the reception frequency used at that time, and the reception frequencies of the slave stations 103-1 to 103-n are automatically changed to the reception frequency of the common signal. Then, the frequency of the broadcast communication is designated by the common signal, and the slave stations 103-1 to 103
It is characterized in that the reception frequency of -n is changed, and the request source of the broadcast communication is made to transmit the broadcast communication at the changed frequency.

In a request assignment satellite communication system in which a plurality of satellite communication earth stations of three or more stations share two or more transmission lines for communication, normally, the master station 102 and the slave stations 103-1 to 103-n are used.
In addition, the common signal processing unit 23 receives the common signal 109 transmitted from the common signal transmission / reception device 105 of the control station 101 via the communication satellite 19 through the demodulation units 21 of the communication signal transmission / reception devices 107 and 108. When the communication signal frequency is specified by the common signal 109 from the control station 101 in this state, the common signal processing unit 23 instructs the communication signal processing unit 24 to set the communication signal frequency by the frequency control signal 25, and Information for notifying the effect is transmitted from the common signal processing unit 23 to the control station 101 through the modulation unit 22, and the communication signal processing unit 24 and the communication signal terminal device 8 perform communication.

From the master station 102 to a plurality of slave stations 103-1 to 10-1
When performing the broadcast communication to the 03-n, the master station 102 uses the common signal 111 to request the broadcast communication to the control station 101, and to the slave stations 103-1 to 103-n. Using the communication signal 112, the communication signal transmitting / receiving device 108 receiving the common signal 109 from the control unit 101 instructs the communication signal receiving frequency to be set to the frequency for broadcast communication determined by the control station 101. Broadcast communication.

A certain slave station 103-1 which is the target of the broadcast communication
In the case where all the communication signal transmitting / receiving devices 108 in the inside are performing communication between the satellite communication earth stations, the control device 104 of the control station 101 transmits the communication signal of one communication signal transmitting / receiving device 108 of the slave station 103-1. The communication stop command transmitter 106 transmits the communication stop command 11 at the same frequency as the reception frequency.
3 is transmitted, and communication of one communication signal transmitting / receiving apparatus 108 in the slave station 103-1 is stopped. As a result, the communication signal transmission / reception device 108 enters a common signal transmission / reception state, sets the communication signal reception frequency to the frequency for broadcast communication determined by the control station 101 by the common signal, and uses the communication signal 112. Broadcast communication.

[0024]

As described above, according to the present invention, 3
Broadcasting from the master station to two or more slave stations using the demand-assigned satellite communication method in which multiple satellite communication earth stations, which are stations or more, communicate by sharing two or more transmission paths according to instructions from the control station. When performing communication, by adding a communication stop command transmitter to the control station, the common signal transmitter / receiver for broadcast communication of each slave station can be deleted, so that the equipment cost of the slave station can be reduced. There is an effect that can be done. This is more effective and economical as the number of slave stations increases.

Further, since the communication stop command transmitter of the control station can send the communication stop command, the time required to stop the communication of one communication signal transmitter / receiver in the slave station and restore the common signal transmission / reception state. In addition to shortening the time, one communication stop command transmitting device can stop the communication of one communication signal transmitting / receiving device in the plurality of slave stations within a short time to bring the common signal transmitting / receiving state.

[Brief description of drawings]

FIG. 1 is a block diagram showing the concept of a broadcast communication network in an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a main part of a communication signal transmitting / receiving apparatus according to an embodiment of the present invention and a conventional example.

FIG. 3 is a flowchart showing an operation flow of the control device of the control station in the embodiment of the present invention.

FIG. 4 is a block diagram showing the concept of a broadcast communication network in a conventional example.

[Explanation of symbols]

 1, 101 Control station 2, 102 Parent station 3-1 to 3-n, 103-1 to 103-n Slave station 4, 104 Control device 5, 105 Common signal transmission / reception device 6 Radio frequency conversion unit 7 Antenna 8 For communication signal Terminal device 9, 13, 107, 108 Communication signal transmitting / receiving device 10, 14 Common signal transmitting / receiving device for broadcast communication 11 Outdoor device 12 Multicarrier control device 15 Common signal for broadcast communication 16, 17, 110, 112 Communication signal 18, 109, 111 Common signal 19 Communication satellite 20 Forced communication disconnection signal 21 Demodulation unit 22 Modulation unit 23 Common signal processing unit 24 Communication signal processing unit 25 Frequency control signal 106 Communication stop command Transmission device 113 Communication stop command

Claims (4)

[Claims] 1. A satellite communication system comprising a master station and a plurality of slave stations which communicate via a communication satellite, and a control station which controls transmission and reception of information between the master station and the plurality of slave stations. The control station is provided with means for transmitting a communication stop command at the frequency received by the slave station which is the target of the generated broadcast communication, and a common signal received by the slave station following the communication stop command. A satellite communication system comprising means for designating the frequency of broadcast communication. 2. The satellite communication system according to claim 1, wherein the control station comprises means for transmitting / receiving a control signal to / from the master station and the slave station via the communication satellite. 3. The satellite communication system according to claim 1, wherein the control station is provided side by side with one of the master station and the slave station. 4. When a control station requests broadcast communication, the control station transmits a communication stop command at the reception frequency used by the slave station targeted for the broadcast communication, The reception frequency of the slave station is automatically switched to the reception frequency of the common signal, and then the reception frequency of the slave station is changed by designating the frequency of the broadcast communication by the common signal, and the request source of the broadcast communication is notified of the change. A method for controlling satellite communication, characterized in that broadcast communication is transmitted at the changed frequency.