JP2003219449A - Mobile communication service providing method, communication network, communication control apparatus and mobile station - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shared mobile communication system in which a connecting delay is reduced in switching a connection destination of a mobile terminal from a system in use to another system, and a reception level measuring method for the shared mobile communication system. <P>SOLUTION: A communication network 220 selects any of cells consisting of a system A and a system B, and provides a mobile communication service to a mobile station 203 in the selected cell. In this case, the network 220 which provides the mobile communication service to the station 203 tries to select the cell consisting of its own system on the basis of the quality information of the cell consisting of its own system notified from the station 203, and if the cell consisting of the own system cannot be selected, the network 220 tries to select a cell consisting of another system notified from the station 203 on the basis of the quality information of the other system. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a communication network having a plurality of communication service systems, selecting one of the cells constituted by each of the communication service systems, and selecting a mobile station in the selected cell. And a mobile communication service providing method for providing a mobile communication service.

[0002]

2. Description of the Related Art As a typical example of a cellular communication system in which commercial services are currently provided in Japan, a digital car telephone system (PDC: Personal Digital Cellu) is used.
lar) 800 MHz band system and 1.5 GHz band system.

The operation mode of this PDC is 800M.
It is common that the Hz band system and the 1.5 GHz band system are operated independently, but the 800 MHz band system and the 1.5 GHz band system are provided by the own system in order to improve the utilization efficiency of the communication channel. It is also possible to select a cell of another system and allocate a communication channel to a mobile station in a standby state or in a communication state using the mobile communication service.

As a communication network that realizes such a mobile communication system, assume that a mobile network has a system A that provides one mobile communication service and a system B that provides another mobile communication service. A cell selection procedure when the system of the mobile communication service provider to be used is switched will be described.

For example, when the mobile station uses the mobile communication service of the system A, the mobile station transmits a communication start request signal to the base station in the system A.
The communication start request signal includes, in the mobile station, the quality information of the cell of the base station in the system A measured in advance, and the quality of the cell of the base station in the system B measured when the mobile station transmits the communication start request. Information and are included.

[0006] Specifically, the cell quality information is provided for each cell constituted by a communication service system (here, system A corresponds) which is a source of mobile communication services used by mobile stations. Includes the cell code as the identification information of the cell (in-use cell code) and the reception level (the in-use cell reception level) at the mobile station of the reception level measurement channel that is the signal transmitted to the cell, and For a cell configured by a communication service system (here, system B corresponds) that is a provider of a mobile communication service that is not used by a station, a cell code (non-use cell code) as identification information of the cell , The reception level at the mobile station of the reception level measurement channel transmitted to the cell (the reception level of the cell not in use) It is made.

Upon receipt of the communication start request signal from the mobile station, the base station of system A sends the communication start request signal
The data is transferred to a control device which is configured in the system A and controls communication between the system A and the mobile station.

The control device in the system A can set the communication channels in ascending order of the reception level of the reception level measurement channel in the mobile station based on the cell quality information included in the transferred communication start request signal. It is determined whether or not there is, and if possible, that cell is selected.

FIG. 1 is a diagram showing an example of the configuration of a cell selection processing unit included in the control device. The cell quality information input interface unit 101 inputs the cell quality information included in the communication start request signal transmitted from the mobile station via the base station, outputs the cell quality information to the cell selection unit 103, and includes the cell quality information. Cell code to cell code buffer section 1
Output to 02.

The cell code buffer unit 102 temporarily stores the input cell code. The cell selection unit 103
Based on the input cell quality information, without distinguishing between the own system and another system, the reception level of the reception level measurement channel in the mobile station is determined in descending order, whether the communication channel can be set, If possible, the cell is selected and the selection result is displayed in the cell code filter unit 10.
Output to 4.

The cell code filter unit 104 reads the cell code of the selected cell from the cell code buffer unit 102 based on the cell selection result by the cell selection unit 103, and selects the selected cell code output interface unit 105.
Output to. Selected cell code output interface section 1
If the cell selected by the cell selection unit 103 is a cell of system B, 05 is configured in system B with the input cell code together with a communication start preparation request signal, and controls communication between system B and the mobile station. To the control device that operates.

The control device in the system B transmits a communication start preparation request signal to the base station in the system B corresponding to the received cell code. To the control device.

The control device in the system A transmits a communication start response signal and a cell code of the selected cell to the mobile station via the base station which has transferred the communication start request signal. After that, a predetermined communication starting procedure such as synchronization establishment is performed between the mobile station and the base station in the system B corresponding to the selected cell, and the communication is started.

[0014]

However, in the above-described cell selection procedure, the control device in the system selects cells in order of high quality without distinguishing between the own system and another system. The system of the mobile communication service provider used by the mobile station is switched depending on the frequency. Therefore, along with the communication start procedure when the system switches, the load on the mobile station is shortened and the battery life is shortened, or the number of signals exchanged between the systems is increased and the system capacity is likely to be compressed. There was a problem.

The present invention solves the above problems, and an object of the present invention is to provide a mobile communication service providing method, a communication network and a communication control device which reduce the load on the mobile station and the communication network.

[0016]

In order to achieve the above object, the present invention, as set forth in claim 1, selects any one of cells constituted by a plurality of communication service systems, and selects the selected cell. In a mobile communication service providing method for providing mobile communication service to mobile stations in a cell,
A communication service system that is providing a mobile communication service to the mobile station attempts to select a cell configured by the local system based on quality information of cells configured by the local system, and a cell configured by the local system. When is not selectable, an attempt is made to select a cell configured by another system based on quality information of a cell configured by another system.

In such a mobile communication service providing method, a cell constituted by a communication service system which is providing the mobile communication service to the mobile station is constituted by a communication service system which does not provide the mobile communication service to the mobile station. Since the selected cells are preferentially selected over the selected cells, the frequency with which the system that provides the mobile communication service used by the mobile station is switched is reduced. That is, along with the communication start procedure when the system is switched, the load on the mobile station is shortened, the battery life is shortened, and the number of signals exchanged between the systems is increased to reduce the frequency of system capacity pressure. The load on the mobile station and the communication network can be reduced.

According to a second aspect of the present invention, in the mobile communication service providing method, a communication service system which is providing a mobile communication service to the mobile station is notified from the mobile station. Obtains the quality information of the cell that the local system configures, and based on the obtained quality information of the cell that the local system configures, tries to select the cell that the local system configures, and the cell that the local system configures When it is not selectable, it requests the mobile station for quality information of a cell configured by another system, acquires the quality information of the cell configured by another system notified by the mobile station, and acquires the quality information. Based on the quality information of the cell configured by the different system, the selection of the cell configured by the different system is attempted.

In this case, the communication service system, which is providing the mobile communication service to the mobile station, does not select the cell configured by another system for the mobile station for the first time when the cell configured by the own system cannot be selected. Request quality information,
Since the mobile station can acquire and transmit the cell quality information of the cell configured by another system only when there is a request, the processing load for the cell acquisition of the cell quality information on the mobile station. Can be reduced.

Further, according to the present invention, in the mobile communication service providing method, the quality information of the cell is the reception level of a reception level measurement channel corresponding to the cell in the mobile station. To be.

As described above, the quality of a cell can be represented accurately by using the quality information of the cell as the reception level of the reception level measurement channel corresponding to the cell in the mobile station.

In order to achieve the above-mentioned object, the present invention has a plurality of communication service systems as set forth in claim 4 and selects one of the cells constituted by each of the communication service systems. In a communication network that provides mobile communication services to mobile stations in the selected cell, a communication service system that is providing mobile communication services to the mobile stations is provided with quality information of cells configured by the own system. Based on the above, the own system cell selecting means that attempts to select a cell included in the own system, and the cell included in another system when the cell included in the own system cannot be selected by the own system cell selecting means. Another system cell selecting means for attempting to select a cell configured by the other system based on the quality information of 1.

In such a communication network, the cell constituted by the communication service system which is providing the mobile communication service to the mobile station provides the mobile communication service to the mobile station, like the invention described in claim 1. Since the cell configured by the communication service system that does not operate is selected with priority, the frequency of switching the system of the mobile communication service providing source used by the mobile station is reduced as compared with the conventional system. That is, along with the communication start procedure when the system is switched, the load on the mobile station is shortened, the battery life is shortened, and the number of signals exchanged between the systems is increased to reduce the frequency of system capacity pressure. The load on the mobile station and the communication network can be reduced.

According to a fifth aspect of the present invention, in the communication network, a communication service system which is providing a mobile communication service to the mobile station is a self system notified from the mobile station. Own system cell quality information acquisition means for acquiring the quality information of the cell configured by, and when the cell configured by the own system cannot be selected by the own system cell selection means, configured by another system for the mobile station Another system cell quality information acquisition means for requesting the quality information of the cell to be transmitted and acquiring the quality information of the cell configured by another system notified from the mobile station.

In this case, similarly to the invention described in claim 2, the communication service system which is providing the mobile communication service to the mobile station, does not select the cell formed by the own system for the first time. To the mobile station, the mobile station can obtain and transmit the quality information of the cell configured by another system only when the mobile station requests the quality information of the cell configured by another system. Therefore, it is possible to reduce the processing load on the mobile station for acquiring cell quality information.

In order to achieve the above object, the present invention is configured in each of a plurality of communication service systems constituting a communication network as described in claim 6, and the communication between the own system and the mobile station. In a communication control device for controlling the system, based on the quality information of cells configured by the own system, the own system cell selection unit that attempts to select a cell configured by the own system, and the own system by the own system cell selection unit. When a cell to be configured cannot be selected, another system cell selecting means that attempts to select a cell configured by the another system based on quality information of the cell configured by another system.

In such a communication control device, as in the invention described in claim 1, the cell constituted by the communication service system which is providing the mobile communication service to the mobile station provides the mobile communication service to the mobile station. Since the cell configured by the communication service system that is not provided is selected with priority, the frequency of switching the system of the mobile communication service provider used by the mobile station is reduced as compared with the conventional system. That is, along with the communication start procedure when the system is switched, the load on the mobile station is shortened, the battery life is shortened, and the number of signals exchanged between the systems is increased to reduce the frequency of system capacity pressure. The load on the mobile station and the communication network can be reduced.

Further, according to the present invention, as described in claim 7, in the communication control device, own system cell quality information acquisition means for acquiring quality information of a cell configured by the own system notified from the mobile station. When the cell configured by the own system cannot be selected by the own system cell selection means, the mobile station requests the mobile station for quality information of the cell configured by another system, and is notified from the mobile station. Another system cell quality information acquisition means for acquiring quality information of a cell configured by another system.

In this case, similarly to the invention described in claim 2, the communication service system which is providing the mobile communication service to the mobile station is the mobile station for the first time when the cell formed by the system itself cannot be selected. To the mobile station, the mobile station can obtain and transmit the quality information of the cell configured by another system only when the mobile station requests the quality information of the cell configured by another system. Therefore, it is possible to reduce the processing load on the mobile station for acquiring cell quality information.

In order to achieve the above-mentioned object, the present invention provides a mobile communication service corresponding to each communication service system provided by a communication network having a plurality of communication service systems as described in claim 8. A first cell quality information acquisition unit that acquires quality information of a cell included in a communication service system that provides a mobile communication service that the mobile station selectively uses, and the first quality. A first cell quality information transmitting means for transmitting the cell quality information acquired by the information acquiring means to the communication network, and a communication service system for providing a mobile communication service not used by the own station from the communication network are configured. Second cell quality information acquisition means for acquiring the quality information of the cell when the quality information of the cell to be processed is requested, The serial quality information of the cell acquired by the second quality information acquisition means and a second cell quality information transmission means for transmitting to the communication network.

In such a mobile station, only when the communication network requests the quality information of the cell constituted by the communication service system which provides the mobile communication service which is not used by the mobile station, the quality information of the cell is requested. Is acquired and transmitted, it is possible to reduce the processing load on the mobile station for acquiring cell quality information.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing a configuration example of the mobile communication system according to the embodiment of the present invention. The mobile communication system 200 shown in the figure includes a mobile station 203 and a communication network 220 that selectively provides a plurality of mobile communication services to the mobile station 203.

The communication network 220 is a system A base station 20 that communicates with mobile stations within the service area 201.
4, a system B base station 205 that communicates with mobile stations in the service area 202, and a system A control device 20 that is connected to the system A base station 204 and performs predetermined communication control.
6 and a system B controller 207 connected to the system A base station 204 and performing a predetermined communication control, and a switching center connected to the system A controller 206 and the system B controller 207 and performing a predetermined exchange operation during communication. 212, and a system A voice processing device 210 that is connected to the system A base station 204 and the switching center 212 and performs predetermined voice processing.
Connected to the system B base station 205 and switching center 212,
A system B voice processing device 211 that performs predetermined voice processing is provided. Of these, the system A base station 204, the system A control device 206, and the system A voice processing device 2
10, the system A as a communication service system that provides one mobile communication service is configured, and the system B base station 205, the system B control device 207, and the system B voice processing device 211 provide another mobile communication service. A system B as a communication service system is configured.

The solid line connecting the components shown in the figure shows the transmission path of the communication signal such as voice data, and the broken line shows the transmission path of the control signal. Note that the mobile communication system in FIG. 2 is a simplified one showing only the components necessary for explaining the present invention, and in reality, there are a plurality of mobile stations, base stations, switching stations, and voice processing devices. However, in the cellular system, for example, the service area is generally divided into cells corresponding to the base stations.

In this mobile communication system 200, the communication network 220 selects one of the cells constituted by the system A and the system B, and provides the mobile communication service to the mobile station 203 in the selected cell. To do. At this time, the system in the communication network 220 that is providing the mobile communication service to the mobile station 203 configures itself based on the quality information of the cell configured by the system notified by the mobile station 203. When cell selection is attempted and the cell configured by the own system cannot be selected, the cell selected by the different system is selected based on the quality information of the cell configured by the different system notified from the mobile station 203. Try.

Hereinafter, both the quality information of the cell configured by the system that provides the mobile communication service being used by the mobile station and the quality information of the cell configured by the system that provides the mobile communication service that is not being used In addition to the description of the first embodiment for simultaneously acquiring the information, the mobile station acquires the quality information of the cell configured by the system that provides the mobile communication service being used, and further uses the quality information when requested by the system. A second embodiment for acquiring cell quality information configured by a system that provides a mobile communication service that is not provided will be described. It is assumed that the mobile station 203 initially receives the mobile communication service provided by the system A. (First Embodiment) FIG. 3 is a diagram showing a configuration example of the mobile station 203. As shown in the figure, the mobile station 203 modulates and decodes signals transmitted and received between the antenna 301 for communicating with the system A, the antenna 302 for communicating with the system B, and the system A. A radio circuit 303 for decoding, a radio circuit 304 for modulation / demodulation and code decoding of a signal transmitted / received between the system B, and a switch 305 for switching a communication partner to either the system A or the system B. , And a control circuit 306 that is connected to an operation unit (not shown) such as a dial and controls various communications.

Here, the mobile station 203 assumes that the system A and the system B use different frequency bands.
Although two antennas 301 and 302 are provided, when system A and system B use the same frequency band, only one antenna is required.

Further, the mobile station 203 is provided with two radio circuits 303 and 304, assuming that the system A and the system B use different modulation / demodulation systems or code decoding systems. If B uses the same modulation / demodulation method or code decoding method, only one radio circuit needs to be provided.

A solid line connecting the constituent elements shown in FIG. 3 shows a transmission line of a communication signal such as voice information, and a broken line shows a transmission line of a control signal.

The control circuit 306 controls the switching of the switch 305 according to the operation of the operation unit by the user. Under the control of the control circuit 306, the switch 305 sets one of the radio device circuits 303 and 304 to the connected state.

The switch 305 is for the radio circuit 3
When 03 is in a connected state, when it is received by the antenna 301 and a communication signal and a control signal are input through the radio circuit 303, the communication signal is output to a microphone, a speaker, a display screen, etc. not shown. However, the control signal is output to the control circuit 306. Similarly, the switch 305 is received by the antenna 302 when the radio circuit 303 is in the connection state, and the radio circuit 30 is received.
When a communication signal and a control signal are input via 4, the communication signal is output to a microphone, a speaker, a display screen, etc., and the control signal is output to the control circuit 306.

Further, the control circuit 306 measures the reception level of the reception level measurement channel transmitted to each cell in the service area 201 of the system A, and
A cell code as identification information of a cell included in the reception level measurement channel is extracted. Similarly, the control circuit 3
06 measures the reception level of the reception level measurement channel transmitted to each cell in the service area 202 of the system B, and extracts the cell code as the identification information of the cell included in the reception level measurement channel. To do.

Next, the control circuit 306 uses the communication start request signal including the cell quality information composed of the reception level and the cell code described above via the switch 303, the radio device circuit 303 and the antenna 301. Base station 204 of system A, which is the source of the existing mobile communication service
Send to.

FIG. 4 is a diagram showing an example of the format of cell quality information. As shown in the figure, the cell quality information is the cell code of the cell for each cell configured by the communication service system (system A here) that is the source of the mobile communication service used by the mobile station 203. Together with the (in-use cell code) and the reception level (in-use cell reception level) at the mobile station 203 of the reception level measurement channel which is a signal transmitted to the cell,
A communication service system (here, system B) that is a provider of a mobile communication service that is not used by the mobile station 203.
For a cell configured by, the cell code as the identification information of the cell (cell code not in use) and the reception level at the mobile station of the reception level measurement channel transmitted to the cell (cell reception level not in use) ) And.

FIG. 5 is a diagram showing a configuration example of a base station in the communication network 220. Although the base station 204 in the system A is illustrated in FIG. 5 as an example, the base station 205 in the system B has the same configuration. As shown in the figure, the base station 204 includes an antenna 401 for communicating with the mobile station 203, a radio device circuit 402 for modulating / demodulating a signal transmitted / received between the mobile station 203, and a communication signal. A separation circuit 403 for separating the control signal,
A voice / data processing device interface (I / F) 404 for transmitting and receiving communication signals to and from a switching center and a control device interface (I / F) 405 for transmitting and receiving control signals to and from the switching center are provided. A solid line connecting the constituent elements shown in FIG. 5 shows a transmission line of a communication signal such as voice information, and a broken line shows a transmission line of a control signal such as a call start request signal.

The signal transmitted from the mobile station 203 is received by the system A base station 204 and the system B 205. Of the received signals, the system A base station 204 outputs a control signal to the system A controller 208 and outputs an audio signal to the system A audio processor 210. Similarly, the system B base station 205 outputs a control signal among the received signals to the system B controller 209 and outputs an audio signal to the system B audio processor 211.

The system A controller 206 includes a cell selection processing section 208. This system A controller 206 is
Based on the cell quality information included in the input communication start request signal, it is determined whether or not the communication channel corresponding to the cell can be set, and if possible, the cell is selected.

FIG. 6 is a diagram showing an example of the configuration of the cell selection processing unit 208 formed in the system A controller 206. In FIG. 6, the cell selection processing unit 208 in the system A controller 206 is taken as an example, but the cell selection processing unit 209 in the system B controller 207 also has the same configuration.

As shown in the figure, the cell selection processing unit 208
Includes an input interface unit 501, a cell code buffer unit 502, an own system cell selection unit 503, a cell code filter unit 504, an output interface unit 505, and another system cell selection unit 506.

The input interface section 501 inputs the cell quality information contained in the communication start request signal transmitted from the mobile station via the base station, and the input system section 501 selects its own system cell selection section 50.
3 and also outputs the cell code included in the cell quality information to the cell code buffer unit 502.

The cell code buffer unit 502 temporarily stores the input cell code. Based on the cell quality information corresponding to the cell configured by the own system (here, system A) among the input cell quality information, the own system cell selection unit 503 determines the cell configured by the own system. It is determined whether or not the communication channel can be set in descending order of the reception level in the mobile station 203 of the reception level measurement channel transmitted to the cell. For example, when all communication channels set for a predetermined cell configured by the own system are in use, the own system cell selection unit 503
Determines that the communication channel cannot be set.

When the communication channel can be set for the cell configured by the own system, the own system cell selection unit 503 selects the cell and outputs the selection result to the cell code filter unit 504.

On the other hand, when the communication channel cannot be set for the cell configured by the own system,
The own system cell selection unit 503 outputs the cell quality information corresponding to another system (here, system B) among the input cell quality information to the other system cell selection unit 506.

The different system cell selection unit 506 measures, on the basis of the inputted cell quality information corresponding to the cell constituted by the different system, the reception level of the cell constituted by the different system, which is transmitted to the cell. Whether or not the communication channel can be set is determined in descending order of the reception level at the mobile station 203 of the working channel.

When a communication channel can be set for a cell configured by another system, another system cell selection section 506 selects the cell and outputs the selection result to cell code filter section 504. On the other hand, if a communication channel can be set for a cell configured by another system, another system cell selection unit 5
06 outputs a notification that there is no cell in which communication can be started to the output interface unit 505 via the cell code filter unit 104.

The cell code filter unit 504 sets the cell code of the selected cell based on the cell selection result by the own system cell selection unit 503 or the cell selection result by the separate system cell selection unit 506. Read from, output interface unit 505
Output to.

When the cell of the different system is selected by the different system cell selecting section 506, the output interface section 505 sends the input cell code together with the communication start preparation request signal together with the mobile station in the different system, system B. It is transmitted to the system B control device 207 which controls communication with 203.

Further, the output interface section 505 is
When the notification that there is no cell in which communication can be started is received from the separate system cell selection unit 506, the notification is transmitted to the system B control device 207.

Controller 2 of system B which is another system
07 transmits a communication start preparation request signal to the system B base station 205 corresponding to the received cell code, and when the preparation for communication start is completed, it transmits that effect to the system A controller 206.

The system A control device 206 transmits a communication start response signal to the mobile station 203 via the system A base station 204 which has transmitted the communication start request signal, and also transmits the cell code of the selected cell. . Then, a predetermined communication start procedure such as synchronization establishment is performed between the mobile station 203 and the system B base station 205 corresponding to the selected cell, and communication is started.

Next, with reference to the sequence diagram shown in FIG. 7, taking as an example a case where the source of the mobile communication service used by the mobile station 203 is switched from the system A in the communication network 220 to the system B, the mobile communication system. The operation of will be described.

As shown in FIG. 7, the mobile station 203 measures the reception level of the reception level measurement channel transmitted to each cell in the service area 201 of the system A, and the service area 202 of the system B. The reception level of the reception level measurement channel transmitted to each cell is measured (step 101). Next mobile station 203
The system A base station 20 transmits a communication start request signal including cell quality information including the measured reception level and the cell code included in the reception level measurement channel.
4 to the system A controller 206 (step 102).

The system A control device 206 determines, based on the cell quality information corresponding to the cell configured by the own system, among the cell quality information included in the received communication start request signal, the cell configured by the own system. For the above, it is determined whether or not the communication channel can be set in descending order of the reception level in the mobile station 203 of the reception level measurement channel transmitted to the cell. When the communication channel cannot be set for the cell configured by the own system, the system A control device 206, based on the cell quality information corresponding to the system B among the received cell quality information, For a cell configured by the another system, it is determined whether or not the communication channel can be set in the descending order of the reception level in the mobile station 203 of the reception level measurement channel transmitted to the cell.

When the communication channel can be set for the cell constituted by the system B (step 1)
In 03), the system A controller 206 selects the cell and transmits the cell code of the selected cell to the system B controller 207 together with the communication start preparation request signal (step 104).

The system B control apparatus 207 sends the system B base station 205 corresponding to the received cell code to
When a communication start preparation request signal is transmitted (step 105) and a report indicating that the communication start preparation is completed is received from the system B base station 205 (step 106), that effect is transmitted to the system A controller 206. (Step 10
7).

The system A controller 206 transmits a communication start response signal to the mobile station 203 via the system A base station 204 which has transmitted the communication start request signal, and also transmits the cell code of the selected cell. (Step 1
08). Thereafter, a predetermined communication start procedure such as synchronization establishment is performed between the mobile station 203 and the system B base station 205 corresponding to the selected cell, and communication is started (step 109). (Second Embodiment) In the second embodiment, the mobile station 203 has the same configuration as in FIG. However, the control circuit 306 measures the reception level of the reception level measurement channel transmitted to each cell in the service area 202 of the system B and measures the reception level, unless there is a request from the system A control device 206. The cell level included in the reception channel is not extracted and the reception level of the reception level measurement channel transmitted to each cell in the service area 201 of the system A is measured and included in the reception level measurement channel. Only the cell code is extracted.

Further, the control circuit 306 uses the communication start request signal including the cell quality information composed of the reception level and the cell code described above via the switch 303, the radio circuit 303 and the antenna 301. Base station 204 of system A, which is the provider of the existing mobile communication service
Send to.

FIG. 8 is a diagram showing an example of a format of cell quality information included in the communication start request signal. As shown in the figure, the cell quality information is the cell code of the cell for each cell configured by the communication service system (system A here) that is the source of the mobile communication service used by the mobile station 203. (In-use cell code) and the reception level (in-use cell reception level) at the mobile station 203 of the reception level measurement channel which is a signal transmitted to the cell.

The base station in the communication network 220 has the same structure as in FIG. The signal transmitted from the mobile station 203 is received by the system A base station 204 and the system B 205. Of the received signals, the system A base station 204 outputs a control signal to the system A controller 208 and outputs an audio signal to the system A audio processor 210. Similarly, the system B base station 205 outputs a control signal among the received signals to the system B controller 209 and outputs an audio signal to the system B audio processor 211.

The system A controller 206 includes a cell selection processing section 208. This system A controller 206 is
Based on the cell quality information included in the input communication start request signal, it is determined whether or not the communication channel corresponding to the cell can be set, and if possible, the cell is selected.

FIG. 9 is a diagram showing an example of the configuration of the cell selection processing section 208 formed in the system A controller 206. In FIG. 9, the cell selection processing unit 208 in the system A controller 206 is taken as an example, but the cell selection processing unit 209 in the system B controller 207 also has the same configuration.

As shown in the figure, the cell selection processing unit 208
Is an input interface unit 601, own system cell code buffer unit 602, own system cell selection unit 603,
Own cell code filter unit 604, output interface unit 605, another system cell quality information request unit 606, input interface unit 607, own system cell code buffer unit 602, own system cell selection unit 603, own system cell code filter unit 604, output An interface unit 605, another system cell quality information request unit 606, an input interface unit 607, another system cell code buffer unit 608, another system cell selection unit 609, and another system cell code filter unit 610 are provided.

The input interface unit 601 has a cell quality corresponding to a cell formed by its own system (here, system A) included in the communication start request signal transmitted from the mobile station 203 via the system A base station 204. Information is input and output to the own system cell selection unit 603, and the cell code included in the cell quality information is output to the own system cell code buffer unit 602.

Local system cell code buffer unit 602
Temporarily stores the input cell code. Based on the input cell quality information corresponding to the cell configured by the local system, the local system cell selection unit 603 determines, for the cell configured by the local system, the reception level measurement channel transmitted to the cell. Mobile station 2
Whether the communication channel can be set is determined in descending order of the reception level in 03.

When the communication channel can be set for the cell configured by the own system, the own system cell selection unit 603 selects the cell and outputs the selection result to the own system cell code filter unit 604. To do.

On the other hand, when the communication channel cannot be set for the cell configured by the own system,
The own system cell selection unit 603 outputs the cell code of the cell configured in advance by the different system (here, system B) to the different system cell quality information requesting unit 606.

Another system cell quality information requesting unit 606 is
The inputted cell code of the cell configured by the system B which is another system is transmitted to the mobile station 203 via the system A base station 204 as a quality information request signal.

The control circuit 306 of the mobile station 203 uses the cell code of the cell formed by the system B as the quality information request signal for the antenna 301 and the radio circuit 303.
And via the switch 305. Next, the control circuit 3
06 measures the reception level of the reception level measurement channel transmitted to each cell in the service area 202 of the system B corresponding to the received cell code, and extracts the cell code included in the reception level measurement channel. And do.

Next, the control circuit 306 sends a quality information response signal containing cell quality information composed of the above-mentioned reception level and cell code to the switch 303 and the radio circuit 3.
02 and the antenna 301 to the base station 204 of the system A that is the provider of the mobile communication service being used.

FIG. 10 is a diagram showing an example of a format of cell quality information included in the quality information response signal. As shown in the figure, the cell quality information is, for each cell configured by the communication service system (system B in this case) that is the provider of the mobile communication service not used by the mobile station 203, the cell code of the cell. (Cell code not in use)
And the reception level of the reception level measurement channel, which is the signal transmitted to the cell, in the mobile station 203 (non-use cell reception level).

The input interface unit 607 includes a cell quality corresponding to a cell formed by another system (here, system B) included in the quality information response signal transmitted from the mobile station 203 via the system A base station 204. The information is input and output to another system cell selection unit 607, and the cell code included in the cell quality information is output to another system cell code buffer unit 608.

Separate system cell code buffer unit 608
Temporarily stores the input cell code. The different system cell selection unit 609, based on the input cell quality information corresponding to the cell formed by the different system, regarding the cell formed by the different system, determines the reception level measurement channel transmitted to the cell. Mobile station 2
Whether the communication channel can be set is determined in descending order of the reception level in 03.

When a communication channel can be set for a cell configured by another system, another system cell selection section 609 selects the cell and outputs the selection result to another system cell code filter section 610. To do.
On the other hand, if the communication channel cannot be set for the cell configured by the different system, the different system cell selection unit 609 notifies the different system cell code filter unit 610 that there is no cell that can start communication. Output to the output interface unit 605.

Separate system cell code filter unit 610
Reads the cell code of the selected cell from the separate system cell code buffer unit 608 based on the cell selection result by the separate system cell selection unit 610 and outputs it to the output interface unit 605.

When the cell of the different system is selected by the different system cell selecting section 609, the output interface section 605 sends the input cell code together with the communication start preparation request signal to the mobile station in the different system, system B. It is transmitted to the system B control device 207 which controls communication with 203.

Further, the output interface unit 605 is
When the notification that there is no cell in which communication can be started is received from the separate system cell selection unit 609, the notification is transmitted to the system B control device 207.

Controller 2 of system B which is another system
07 transmits a communication start preparation request signal to the system B base station 205 corresponding to the received cell code, and when the preparation for communication start is completed, it transmits that effect to the system A controller 206.

The system A control device 206 transmits a communication start response signal to the mobile station 203 via the system A base station 204 which has transmitted the communication start request signal, and also transmits the cell code of the selected cell. . Then, a predetermined communication start procedure such as synchronization establishment is performed between the mobile station 203 and the system B base station 205 corresponding to the selected cell, and communication is started.

Next, referring to the sequence diagram shown in FIG. 11, taking as an example the case where the source of the mobile communication service used by the mobile station 203 is switched from the system A in the communication network 220 to the system B, the mobile communication system. The operation of will be described.

As shown in FIG. 11, the mobile station 203 measures the reception level of the reception level measurement channel transmitted to each cell in the service area 201 of the system A (step 201). Next, the mobile station 203 sends a communication start request signal including cell quality information composed of the measured reception level and the cell code included in the reception level measurement channel to the system A via the system A base station 204. It is transmitted to the control device 206 (step 202).

Based on the cell quality information corresponding to the cell configured by the own system, which is included in the received communication start request signal, the system A control device 206 determines the cell configured by the own system as the cell. Mobile station 203 of the received reception level measurement channel
It is determined whether or not the communication channel can be set in descending order of the reception level in. Then, when the communication channel cannot be set for the cell configured by the own system (step 203), the system A control device 206 sets the cell code of the cell configured by the system B as a quality information request signal. , To the mobile station 203 via the system A base station 204 (step 20).
4).

System B as the quality information request signal
The mobile station 203, which has received the cell code of the cell configured by, measures the reception level of the reception level measurement channel transmitted to each cell in the service area 202 of the system B corresponding to the cell code (step). Two
05). Next, the mobile station 203 sends a quality information response signal including cell quality information including the measured reception level and the cell code included in the reception level measurement channel to the system A base station 204 via the system A base station 204. It is transmitted to the control device 206 (step 206).

Based on the received cell quality information corresponding to the system B, the system A control unit 206, for the cell constituted by the other system, the mobile station 203 of the reception level measurement channel transmitted to the cell.
It is determined whether or not the communication channel can be set in descending order of the reception level in.

When the communication channel can be set for the cell constituted by the system B (step 2)
In 07), the system A controller 206 selects the cell and transmits the cell code of the selected cell together with the communication start preparation request signal to the system B controller 207 (step 208).

The system B control unit 207 sends the system B base station 205 corresponding to the received cell code to
When a communication start preparation request signal is transmitted (step 209) and a report that the communication start preparation is completed is received from the system B base station 205 (step 210), that effect is transmitted to the system A controller 206. (Step 21
1).

The system A controller 206 transmits a communication start response signal to the mobile station 203 via the system A base station 204 which has transmitted the communication start request signal, and also transmits the cell code of the selected cell. (Step 2
12). After that, a predetermined communication start procedure such as synchronization establishment is performed between the mobile station 203 and the system B base station 205 corresponding to the selected cell, and communication is started (step 213).

As described above, in the mobile communication system 200 of this embodiment, the communication network 220 first attempts to select a cell configured by the system that is the source of the mobile communication service used by the mobile station 203, If the cell cannot be selected, an attempt is made to select a cell that is not used by the mobile station 203 and is configured by the system that is the source of the mobile communication service. Therefore, the cell configured by the system that is providing the mobile communication service to the mobile station 203 is preferentially selected over the cell configured by the system that does not provide the mobile communication service to the mobile station 203. The frequency of switching the system of the mobile communication service providing source used by the mobile station 203 is reduced as compared with the conventional system. That is, along with the communication start procedure when the system is switched, the load on the mobile station 203 is shortened, the battery duration is shortened, and the number of signals exchanged between the systems is increased, resulting in the frequency of system capacity being compressed. Decreased,
The load on the mobile station 203 and the communication network 220 can be reduced.

In the embodiment described above, the mobile station 20
3 was initially described as receiving the mobile communication service provided by the system A, but the same can be considered when initially receiving the mobile communication service provided by the system B.

In each of the above embodiments, the own system cell selection units 503 and 603 in the cell selection processing unit 208 correspond to the own system cell selection means, and the separate system cell selection unit 5
06 and 609 correspond to different system cell selecting means. Further, the input interface unit 601 in the cell selection processing unit 208 corresponds to the own system cell quality information acquisition unit, and the separate system cell quality information request unit 606 and the input interface unit 607 correspond to the separate system cell quality information acquisition unit.

Further, the control circuit 306 in the mobile station 203 corresponds to the first and second theoretical quality information obtaining means, and the antenna 302 and the radio circuit 303 correspond to the first and second cell quality information transmitting means. To do.

[0101]

As described above, according to the invention described in claims 1, 4 and 6, the cell constituted by the communication service system which is providing the mobile communication service to the mobile station moves to the mobile station. Since the cell configured by the communication service system that does not provide the communication service is selected with priority, the frequency of switching the system of the mobile communication service providing source used by the mobile station is reduced as compared with the conventional system. That is, along with the communication start procedure when the system is switched, the load on the mobile station is shortened, the battery life is shortened, and the number of signals exchanged between the systems is increased to reduce the frequency of system capacity pressure. The load on the mobile station and the communication network can be reduced.

Further, according to the invention described in claims 2, 5 and 7, the communication service system which is providing the mobile communication service to the mobile station is not provided until the cell formed by the own system cannot be selected. Request the quality information of the cell configured by another system from the mobile station, and only when requested, the mobile station acquires and transmits the quality information of the cell configured by another system. Therefore, it is possible to reduce the processing load on the mobile station for acquiring cell quality information.

According to the third aspect of the invention, the quality of the cell is accurately represented by using the quality information of the cell as the reception level of the reception level measurement channel corresponding to the cell in the mobile station. It will be possible.

Further, according to the invention described in claim 8, the mobile station transmits the quality information of the cell constituted by the communication service system which provides the mobile communication service in which the communication network is not used by the mobile station. Since the quality information of the cell is acquired and transmitted only when the request is made, the processing load on the mobile station for acquiring the quality information of the cell can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a cell selection processing unit configured in a conventional control device.

FIG. 2 is a diagram showing a configuration example of a mobile communication system of the present embodiment.

FIG. 3 is a diagram showing a configuration example of a mobile station of the present embodiment.

FIG. 4 is a diagram showing an example of a format of cell quality information in the first embodiment.

FIG. 5 is a diagram showing a configuration example of a base station in the present embodiment.

FIG. 6 is a diagram illustrating a configuration example of a cell selection processing unit configured in the control device according to the first embodiment.

FIG. 7 is a sequence diagram showing an operation of the mobile communication system in the first embodiment.

FIG. 8 is a diagram showing an example of a format of cell quality information in the second embodiment.

FIG. 9 is a diagram illustrating a configuration example of a cell selection processing unit configured in a control device according to a second embodiment.

FIG. 10 is a diagram showing another example of the format of cell quality information in the second embodiment.

FIG. 11 is a sequence diagram showing an operation of the mobile communication system in the second embodiment.

[Explanation of symbols]

200 mobile communication system 201,202 Service area 203 mobile station 204, 205 Base station 206, 207 control device 208, 209 Cell selection processing unit 210, 211 voice processing device 212 Exchange 220 communication network 301, 302, 401 antenna 303, 304, 402 radio circuit 305 switch 306 Control circuit 403 Separation circuit 404 Voice / data processing device I / F 405 Control device I / F 501, 601, 607 Input interface section 502 Cell code buffer section 503, 603 Own system cell selection unit 504 Cell code filter section 505,605 Output interface section 602 Own system cell code buffer section 604 Own system cell code filter 606 Separate system cell quality information request unit 607 Separate system cell code buffer section 608 Separate system cell code filter section

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Seigo Harano             2-11-1, Nagatacho, Chiyoda-ku, Tokyo Stock             Ceremony company NTT Docomo F term (reference) 5K067 AA14 DD19 DD43 DD44 EE04                       EE10 EE16 EE24 EE56 JJ72

Claims (8)

[Claims] 1. A mobile communication service providing method for selecting a cell configured by a plurality of communication service systems and providing a mobile communication service to a mobile station within the selected cell, comprising: The mobile communication system providing the mobile communication service to the mobile terminal attempts to select the cell configured by the local system based on the quality information of the cell configured by the local system, and the cell configured by the local system cannot be selected. In this case, a method for providing a mobile communication service, which attempts to select a cell configured by the different system based on quality information of the cell configured by the different system. 2. The mobile communication service providing method according to claim 1, wherein the communication service system that is providing the mobile communication service to the mobile station is a cell configured by its own system notified from the mobile station. If quality information is acquired, an attempt is made to select a cell configured by the local system based on the acquired quality information of the cell configured by the local system, and if the cell configured by the local system cannot be selected, the movement is performed. Requesting the quality information of the cell configured by another system to the station, acquiring the quality information of the cell configured by another system notified from the mobile station, the cell configured by the acquired another system A mobile communication service providing method for attempting to select a cell configured by the other system based on the quality information of the above. 3. The mobile communication service providing method according to claim 1, wherein the quality information of the cell is a reception level of a reception level measurement channel corresponding to the cell in the mobile station. Method. 4. A communication having a plurality of communication service systems, selecting any one of cells configured by each of the communication service systems, and providing mobile communication services to mobile stations in the selected cells. In the network, a communication service system that is providing a mobile communication service to the mobile station, and own system cell selecting means that attempts to select a cell included in the own system based on quality information of a cell included in the own system. And when the cell configured by the local system cannot be selected by the local system cell selection unit, based on the quality information of the cell configured by another system, another cell configured by the another system is selected. A communication network comprising system cell selecting means. 5. The communication network according to claim 4, wherein the communication service system that is providing the mobile communication service to the mobile station is provided with the quality information of the cell configured by the own system notified from the mobile station. Obtaining own system cell quality information obtaining means, and when the cell configured by the own system cannot be selected by the own system cell selecting means, requests the mobile station for quality information of the cell configured by another system. And a separate system cell quality information obtaining unit that obtains quality information of a cell configured by a different system notified from the mobile station. 6. A communication control device configured in each of a plurality of communication service systems constituting a communication network and controlling communication between the own system and a mobile station, based on quality information of cells formed by the own system, Own system cell selecting means for attempting to select a cell configured by the own system, and quality information of a cell configured by another system when the cell configured by the own system cannot be selected by the own system cell selecting means. Another system cell selecting means that attempts to select a cell configured by the other system based on the communication control device. 7. The communication control device according to claim 6, wherein the own system cell quality information obtaining unit obtains quality information of a cell included in the own system notified from the mobile station, and the own system cell selecting unit. When the cell configured by the local system is not selectable by the mobile station, the mobile station requests the mobile station for the quality information of the cell configured by the different system, and is notified by the mobile station by the different system. Another system cell quality information acquisition means for acquiring the quality information of the communication control device. 8. A mobile station that selectively uses a mobile communication service corresponding to each of the communication service systems provided by a communication network having a plurality of communication service systems, and provides the mobile communication service used by the own station. A first cell quality information acquisition unit that acquires quality information of a cell included in the communication service system, and a first cell quality information acquisition unit that transmits the quality information of the cell acquired by the first quality information acquisition unit to the communication network. Cell quality information transmitting means, and when the quality information of a cell configured by a communication service system that provides a mobile communication service not used by the own station is requested from the communication network, the quality information of the cell is acquired. 2 cell quality information acquisition means, and the cell quality information acquired by the second quality information acquisition means Mobile station comprising a second cell quality information transmission means for transmitting to the signal network.