JPS6354263B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mobile communication system in which communication is performed with a mobile station through one of a plurality of distributed radio base stations, in which a radio line used for communication between the radio base station and the mobile station is used. Regarding the wireless line control method to be set.

As a conventional mobile communication system of this type, there is a car telephone system, which provides a control line for setting up a wireless line between a base station and a mobile station in order to effectively utilize radio waves. The movement range of a mobile station is divided into a plurality of radio zones, each radio zone is provided with a radio base station, and the mobile station communicates through the radio base station of the radio zone to which it currently belongs. When setting up a wireless link between a base station and a mobile station, the level is measured at the base station and compared with each other. The disadvantage was that the operation required extremely complicated control.

This invention controls the frequency and time of radio waves transmitted from a wireless base station to indicate an empty line, and the mobile station detects the presence or absence of an empty line signal using a designated frequency using a non-locating cyclic method. The aim is to simplify the control and equipment for this purpose.

FIG. 1 shows an embodiment of the present invention, in which a telephone switching communication network is constituted by a terminal office (switching center) 11 housing a general subscriber telephone 10 and a central office (switching center) 12. Base station S ₁ ...Sn is also communication line 1
It has been accommodated through 4. A radio control station 15 is connected to the central station 12, and the radio control station 15 is connected to the control line 1.
6 to each wireless base station _S1 ...Sn. In addition to the transmitter/receiver, the mobile station 17 also has a device for making calls, receiving calls,
A call end push button 18, a dial button 19, a storage section 21, and the like are provided.

If a call is made from the subscriber telephone 10a to the mobile station 17, the dial signal will be sent to the terminal station 1.
1. Sent to radio control station 15 via central station 12. The radio control station 15 stores whether or not the mobile station 17 exists within its own service area, and if the mobile station 17 exists in another service area, it transfers the dial signal to the control station in that service area. do.

On the other hand, if the mobile station 17 exists in the service area of the control station 15, the control station 15 centrally
In a dead area such as an underground mall, mobile stations 17 are called using a specific channel (P channel) in a distributed manner (there is also a method of dispersing all stations). The wireless base station Sa is installed in an underground mall, and is controlled by a control station 15 to transmit a specific channel P. The mobile station 17 constantly monitors the P channel, and only when the mobile station 17 is called, stores the calling number following the called number in the storage unit 21, and notifies the holder of the mobile station 17 that there has been an incoming call. Notify with a bell etc. The holder of mobile station 17 answers the incoming call by pressing pushbutton 18. When the pushbutton 18 is pressed, the mobile station 17
The synthesizer operates, and the designated transmitting and receiving frequencies are sequentially circulated non-locally.

The wireless base stations S ₁ ...Sn intermittently transmit radio waves modulated with antenna signals. Intermittent transmission makes it easy to reuse the same frequency at another base station. Mobile station 17 is a wireless base station
When a radio wave of S ₁ is received and an idle wire signal is detected, the synthesizer stops operating only at that time and fixes the reception frequency to f ₁ at that time. The mobile station 1
7 transmits the reserve signal using a radio wave of frequency F ₁ (an upstream radio wave corresponding to f ₁ ). When the radio base station S ₁ receives the reserve signal, it stops sending out the idle signal and notifies the control station 15 of this fact. The control station 15 is connected to wireless base stations S ₂ and S ₃ that are close to the wireless base station S ₁
The use of _F1 radio waves is prohibited. For example, if there is a wireless base station _S3 that is transmitting an idle signal using _f1 at a timing different from that of wireless base station S1, the control station ₁₅ will send a different frequency and transmission timing to the wireless base station _S3 . specify.

Note that the receiver of the wireless base station S ₁ receives the radio wave F ₁ , but operates only when the transmission radio wave f ₁ is being sent out. The radio base station S ₁ notifies the control station 15 of the use of f ₁ and then connects the radio line and the telephone line.
The mobile station 17 sends the called identification number and the subscriber telephone 1.
0a is sent, and the mobile station 17 and subscriber telephone 10a are connected. When a call is made from the mobile station 17, the line is set using the pushbutton 18, and then the dialing button 19 is operated to dial the number.

With this configuration, even if there are many radio base stations in close proximity, the mobile station 17 can uniquely select one radio base station, and the selection is even if the mobile station and one radio This can be done only with the base station, and there is no need for control by the control station 15.
That is, the control station 15 only needs to specify the frequency and transmission timing in advance so as not to interfere with the radio base station, and the control amount of the control station 15 can be reduced compared to the conventional system, and the mobile station 17, Each control circuit of the control station 15 and the wireless base stations _S1 ...Sn can also be simplified.

As explained above, according to the present invention, since a wireless channel can be set between a wireless base station and a mobile station, the wireless system can be controlled regardless of the control method of the wired transmission line system. be. Even when a mobile radio device such as a pager is used as a mobile station and a large number of radio base stations are installed such as public telephones, according to the present invention, by reducing the service area of the transceiver of the radio base station, Even if wireless base stations are installed close together, a small amount of radio waves can be used effectively, and the communication line can be set up very easily.

[Brief explanation of the drawing]

The figure is a block diagram showing an embodiment of the invention. 10, 10a: general subscriber telephone, 11: terminal office (exchange), 12: central office (exchange), 14: telephone line, 15: radio control station, 16: control line, 17: mobile station, 18: Push button for calling, receiving, and ending calls, 1
9: Dial button, 21: Memory section, S ₁ ...Sn:
Wireless base station.

Claims (1)

[Claims] 1 In a mobile communication system in which multiple wireless base stations are installed in a distributed manner and mobile stations communicate through nearby wireless base stations, each wireless base station transmits radio waves at a pre-designated frequency when it is idle. The mobile station modulates the signal and transmits it at a fixed timing while shifting the frequency or timing between the wireless base stations, and the mobile station searches for the idle signal in non-locating circulation.
A wireless line control method for a mobile communication system, characterized in that when this is detected, the search is stopped and the wireless line at that time is used as a communication line.