JPH0724433B2 - Channel blocking method in distributed MCA method - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of use] The present invention relates to a distributed MCA system used in a prefectural disaster prevention administration radio system or the like.

SUMMARY OF THE INVENTION The present invention provides a shared wave used across each relay station,
When a test radio wave is emitted by station operation at the time of maintenance at any relay station, if the same frequency channel of another relay station is available, the same frequency interference will occur and communication will be difficult. When the shared wave of the relay station is set to the test state, the information is transmitted to the central control circuit of the control station by using the data line (channel) of the multiplex radio line, and another relay station that uses the same frequency The blocking information is transmitted to the parent wireless device by using the data channel of the multiplex wireless line, and the parent wireless device is blocked to prevent interference.

[Conventional technology]

Conventionally, even if a common wave with the same frequency exists in another relay station,
Since the information for blocking the parent wireless device of the other relay station was not transmitted by the test information as in the present invention, when used at the same time, interference occurred depending on the line condition, which hindered the call. As a countermeasure against this, at the most, a person monitors the call channel on the control station side, and the maintenance person of the other relay station asks the maintenance person of the other relay station to use the order wire line (meeting call line) of multiple wireless lines.
However, it was difficult to completely prevent interference because it was only covered by operations such as giving permission to emit test radio waves.

[Problems to be Solved by the Invention]

In the conventional case, as described above, there is a drawback that interference is caused in the shared wave of other relay stations during the maintenance test. In order to solve this drawback, it is an object of the present invention to automatically block the parent wireless device of the shared wave of another relay station to prevent interference.

[Means and Actions for Solving the Problems]

In order to achieve the above object, the present invention provides a state in which when a maintenance person puts a parent wireless device of a relay station into a test (station operation) state,
The information is transmitted to the central control unit of the control station via the data channel of the multiplex radio line, and the central control unit transmits the frequency to all other relay stations using the frequency according to the preset shared wave information. The information for blocking the parent wireless device of the same frequency is transmitted through the data channel of the multiplex wireless line, and the parent wireless device is blocked so that radio waves are not emitted.

〔Example〕

FIG. 1 is a system diagram for explaining the present invention, and shows only main devices.

A central control unit 1 is installed in the control station to monitor and control the use state of the master radio unit 4 of all relay stations (master station), and usually control so that the shared wave is not used at two locations at the same time. To do. Alternatively, it is shown in the form of a multi-radio device including a carrier terminal device. Reference numeral 3 is a switching device for switching and connecting the communication line 6. Reference numeral 5 denotes a data line (channel) of the multiplex radio line, which is an information transmission line for information transmission according to the present invention.

FIG. 2 is a diagram for making the flow of information transmission according to the present invention easier to understand. When the maintenance person puts the master wireless device of any channel among the master wireless devices 4 of the relay station A into a test state,
The channel test information 7 is transmitted to the central control unit 1 by the data line 5. The central control unit 1 selects the parent radio unit 4 of another relay station having the same frequency as the parent radio unit under test of the relay station A from the preset frequency allocation information, and uses the data line 5 to set the channel blockage information. 8 is transmitted to the relay station B and other corresponding relay stations. The parent wireless device 4 which has received the channel blocking information 8 prohibits the transmission activation until this information is released.

〔The invention's effect〕

According to the present invention, it is possible to automatically avoid common wave interference during maintenance and always provide good wireless communication.

Especially, as data transmission such as facsimile has become widespread recently, this interference prevention measure is very effective.

[Brief description of drawings]

FIG. 1 is a system diagram for explaining the present invention, and FIG. 2 is a diagram showing an information flow of the present invention. 1: Central control unit, 2: Multiplex wireless device, 3: Switching device, 4: Parent wireless device, 5: Data line, 6: Call line, 7: Channel test information, 8:
Channel blockage information.

Claims (1)

[Claims] 1. A master station having a plurality of relay stations as master stations, the master stations having a number of channels corresponding to the number of channels installed in the relay stations.
In a distributed MCA wireless telephone system in which frequencies above the channel are shared by the parent wireless devices of each relay station,
By connecting and transmitting the station operation status information of the master radio equipment of each channel of each relay station to the central control equipment of the control station via the data line of the multiple radio line, the radio waves of the same frequency of the MCA system are simultaneously emitted from other relay stations. A channel blockage method in the distributed MCA method, which is characterized in that it is prevented.