JPH02266723A - Mobile communication system - Google Patents

Abstract

PURPOSE:To monitor a mobile station even from any point in the wave covering area of a base station by setting the same number as that of the mobile station to be monitored selectively, receiving a connection signal on a wave to the mobile station to be monitored, and making it tune with the same frequency as that of the voice line of the mobile station. CONSTITUTION:The same value as that set on the number register 25 of an incoming mobile station 17 is set fixedly on the number register 29 of a monitoring mobile station 18. Therefore, a call signal to set the incoming mobile station 17 to be sent to the down carrier 31 of a radio base station 12 as an address is received as a signal addressed to its own station by the monitoring mobile station 18. At such a case, the monitoring mobile station 18 makes a frequency designated by the allocation of the voice line tune with that of the voice line of the down carrier 31, and a voice line monitoring operation is started from that time. In such a way, the monitoring mobile station 18 can change a place to be monitored if it is within the wave covering area 14, and also, can move while monitoring.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mobile communication system capable of monitoring mobile stations.

[Conventional technology]

In a mobile communication system, mobile stations that move within the radio wave coverage area of a base station communicate with each other via the base station. When monitoring lines in such a mobile communication system, a monitoring trunk circuit is connected to the wired voice line of the exchange, and the voice is monitored using this trunk circuit.

[Problem to be solved by the invention]

As described above, in conventional mobile communication systems, trunk circuits dedicated to monitoring were used and monitoring was performed over wires.

Therefore, there has been a problem in that the monitoring location cannot be easily changed.

Another problem is that it is necessary to newly install a leased line or a public line to connect a new line for monitoring at a point far away from the exchange and that point.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a mobile communication system that allows mobile stations to be monitored from any point within the radio wave coverage area of a base station.

[Means to solve the problem]

In the present invention, (i) an exchange, (ii) one or more wireless base stations connected to this exchange, and (iii)
Multiple mobile stations that move within the radio wave coverage area covered by the radio waves of this radio base station and perform wireless communication via this radio base station, and (iv) Select and set the same number as the number of the mobile station to be monitored. The mobile communication system is equipped with a monitor mobile station that receives a connection signal on radio waves to the mobile station to be monitored and performs monitoring while tuning to the same frequency as the voice line of the mobile station.

That is, in the present invention, a radio base station that selects and sets the same number as the mobile station to be monitored is arranged as a monitor station. Although this wireless base station does not transmit upstream radio waves, it can receive the connection signal on the radio waves to the mobile station, tune to the same frequency as the voice line of the monitored mobile station, and monitor the voice. Desired mobile stations can be monitored within the base station's radio wave coverage area.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to Examples.

FIG. 1 shows the configuration of a mobile communication system in one embodiment of the present invention. In the mobile communication system of this embodiment, a wireless base station 12 for performing wireless transmission and reception is connected to an exchange 11. The antenna 13 of the wireless base station 12 has a radio wave coverage area 14 of a predetermined range. That is, a plurality of mobile stations existing within this radio wave coverage area 14 can perform necessary communications via the radio base station 12.

It is assumed that a calling mobile station 16 existing within this radio base station 14 makes a call, a receiving mobile station 17 receives the call, and communication is performed between the two. The monitor mobile station 18 is a movable station that monitors communication between the two parties through the wireless base station 12. The originating mobile station 16 includes a transceiver 21 and an antenna 22 for transmitting and receiving. The receiving mobile station 17 is equipped with a transceiver 23, an antenna 24, and a number register 25. The dial number of this called mobile station is registered in the number register 25. The monitor mobile station 18 includes a receiver 27, a reception-only antenna 28, and a number register 29. The number register 29 of the monitor mobile station 18 in this embodiment includes the number register 25 of the called mobile station 17.
The same content is fixedly set. In this embodiment, one of the mobile stations 16 and 17 is used for sending and the other is used for receiving, but the present invention is not limited to this.

In the mobile communication system configured as described above, the operation of the system is based on the premise that the originating mobile station 16, the terminating mobile station 17, and the monitor mobile station 18 are all located within the radio wave coverage area 14 of the radio base station 12. Explain.

The originating mobile station 16 sends the dial number of the terminating mobile station 17 to the radio base station 14 when making the call. When the radio base station 14 receives this dial number, it sends it to the exchange 11. The exchange 11 analyzes this dialed number, causes the radio base station 14 to send out a paging signal, and starts connection processing.

FIG. 2 shows the line connection sequence in this example.

That is, when the radio base station 14 sends out a paging signal (step 2), the paging signal reaches not only the receiving mobile station 17 but also the monitor mobile station 18.

The calling signal includes the dial number of the called mobile station 17. The same value as the value set in the number register 25 of the receiving mobile station 17 is fixedly set in the number register 29 of the monitor mobile station 18. Therefore, a paging signal sent out on the downlink carrier 31 of the wireless base station 12 and destined for the called mobile station 17 is also received by the monitor mobile station 18 as a signal addressed to the mobile station itself.

Upon receiving the paging signal, the receiving mobile station 17 transmits a paging response (step ■) to the radio base station 14 (step ■). When the radio base station 14 receives this, it transmits the voice line assignment to the receiving mobile station 17 (step
). This voice line assignment is received by both the destination mobile station 17 and the monitor mobile station 18.

The receiving mobile station 17 tunes the frequency designated by this voice line allocation to the voice lines of the down carrier 31 and up carrier 32. On the other hand, the monitor mobile station 18 tunes the frequency specified in the voice line allocation to the voice line of the downlink carrier, and from this point on, the voice line monitoring operation (
Step (3) is started to monitor the downlink carrier for the terminating mobile station 17.

On the other hand, the receiving mobile station 17 transmits the carrier of the assigned frequency to the radio base station 14 as a monitoring sound (step 2). When the wireless base station 14 receives this monitoring sound,
An incoming call instruction is sent to the incoming mobile station 17 (step 2). Upon receiving the incoming call instruction, the receiving mobile station 17 sends a paging signal to the called party (step 2). Further, the receiving mobile station 17 sends an incoming call instruction response to the radio base station 14 (step 2).

When the called party responds upon hearing the paging signal (step 2), the called mobile station 17 sends a response to the radio base station 14. As a result, the call becomes active (step ■), and the call setting is completed.

〔Effect of the invention〕

As explained above, according to the present invention, a monitor mobile station is provided, and this monitor mobile station receives a connection signal on radio waves to a mobile station to be monitored, and receives a signal on the same frequency as the voice line of the mobile station. Monitor in tune with. Therefore, the monitoring mobile station can change the monitoring location at any time as long as it is within the radio wave coverage area, and can also move from one location to another while monitoring. Furthermore, since the mobile communication system of the present invention performs monitoring wirelessly, it also has the effect of eliminating the need for a dedicated line for monitoring.

[Brief explanation of drawings]

The drawings are for explaining one embodiment of the present invention, of which FIG. 1 is a system configuration diagram of a mobile communication system, and FIG. 2 is a sequence explanatory diagram showing a line connection sequence. 11... Exchange, 12... Wireless base station, 6... Originating mobile station, 17... Terminating mobile station, 8... Monitor Mobile station, 1... Down carrier, 2... Up carrier. Figure 31 application submitted by Mr. NEC Co., Ltd.

Claims (1)

[Claims] An exchange, one or more wireless base stations connected to the exchange, and wireless communication via the wireless base station that moves within the radio wave coverage area covered by the radio waves of the wireless base station. Select and set the same number as the number of the mobile station to be monitored, and receive the connection signal on the radio wave to the mobile station to be monitored, and connect the same frequency as the voice line of the mobile station. A mobile communication system comprising: a monitor mobile station that performs monitoring in synchronization with the mobile station.