JP2888220B2 - Mobile communication system, data transmission method, and mobile communication terminal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication system, and more particularly, to a mobile communication system, a data transmission method, and a mobile communication terminal capable of performing two-way communication between a mobile terminal and a base station.

[0002]

2. Description of the Related Art Various mobile communication systems capable of performing bidirectional communication between a mobile terminal and a base station have been proposed.

In the paging communication system disclosed in Japanese Patent Application Laid-Open No. 62-269524, a mobile terminal detecting a paging signal from a radio base station returns a response signal to the radio base station, and the response signal is transmitted to the radio base station. Sent from station to control station. In the paging system disclosed in Japanese Patent Application Laid-Open No. 3-38122, when a base station transmits a calling signal, the called pager returns a predetermined recognition signal, and when the base station receives the recognition signal, a call is generated. Notify the caller that the call signal has arrived. Further, JP-A-63-1
Japanese Patent Application Publication No. 74433 discloses a selective call receiving apparatus having a function of calling a response destination when a response request is received in a received message.

[0004] In addition, since mobile terminals carried by users are usually battery-powered, it is desirable that their power consumption be reduced as much as possible. A wireless telephone device aiming at such low power consumption is disclosed in Japanese Patent Application Laid-Open No. 7-303077. This wireless telephone device is provided with a battery remaining amount detecting unit, and when the battery remaining amount is equal to or more than a predetermined value, the position is registered each time the mobile communication area (cell) is moved.
If the remaining battery power is equal to or less than the predetermined value, the user is only notified of invalid position registration. Also, by changing the time interval of receiving a control signal from the base station and changing the location registration according to the remaining battery power, the battery consumption is suppressed and the usable time is extended.

[0005]

However, in a system using the above-mentioned conventional paging system, a terminal that has received a call using a single area of a wide area selective call system transmits a response signal to a base station and makes a call. This method is effective only in the area of the wide area selective call radio area, and is not sufficient in terms of efficiency and reliability as a two-way communication system.

In the above-mentioned radio telephone apparatus, location registration performed every time a cell is moved requires a large amount of power to drive a transmission power amplifier. For this reason, the consumption of the battery is increased, and the usable time cannot be sufficiently extended.

An object of the present invention is to provide a mobile communication system and a mobile communication device capable of two-way communication capable of reducing power consumption.

It is another object of the present invention to provide a mobile communication system and a data transmission method that improve the efficiency and reliability of data transmission from a base station to a mobile terminal.

[0009]

SUMMARY OF THE INVENTION A mobile communication system according to the present invention comprises a wide area base station forming a wide area unidirectional communication area (wide area), and a plurality of cells forming a cellular bidirectional communication area (cell). A cell base station, a mobile communication terminal,
A control station that controls the wide area base station and the plurality of cell base stations, and further, the mobile communication terminal includes a receiving unit for receiving a radio signal from the wide area base station,
Transmitting / receiving means for performing bidirectional communication with a first cell base station forming a bidirectional communication area in which the mobile communication terminal exists, and determining whether a radio signal from the wide area base station can be received Determining means, and when it is determined that a radio signal from the wide area base station is receivable, when receiving an activation signal from the wide area base station, activates the transmitting / receiving means to generate a response signal to the activation signal. Transmit to the first cell base station, and when it is determined that the radio signal from the wide area base station is unreceivable, activate the transmitting and receiving means and transmit terminal information indicating out of the wide area unidirectional communication area. First
Transmitting to the cell base station, and further comprising:
Communication control means for setting a standby state to wait for a signal from a cell base station; andthe control station includes: storage means for storing a message addressed to the mobile communication terminal; and In the case where the mobile communication terminal is located within the communication area, the startup signal transmission control means for transmitting the activation signal to the mobile communication terminal through the wide area base station, and the response signal is received from the mobile communication terminal through the first cell base station. Sometimes transmitting the message stored in the storage means to the mobile communication terminal through the first cell base station, and transmitting the activation signal when the mobile communication terminal is out of the wide area unidirectional communication area. Transmission control means for transmitting a message stored in the storage means to the mobile communication terminal through the first cell base station. And it features.

Further, the activation signal transmission control means transmits the activation signal a predetermined number of times when the response signal is not received, and transmits the activation signal even if the activation signal is transmitted the predetermined number of times. If no response signal is received, the message is transmitted to the mobile communication terminal through the wide area base station, and the communication control means of the mobile communication terminal always keeps the receiving means in the intermittent reception state.

[0011] In the data transmission method according to the present invention, when data destined for the mobile communication terminal is accumulated, the control station transmits an activation signal destined for the mobile communication terminal through the wide area base station. In response to the activation signal from the wide area base station, activates the transmission / reception unit for two-way communication, transmits a response signal to the control station through the first cell base station, and the control station receives the response signal. The message is transmitted to the mobile communication terminal through the first cell base station, and the mobile communication terminal intermittently receives the message from the first cell base station.

[0012] Further, when it is determined that the radio signal from the wide area base station cannot be received, the mobile communication terminal activates the two-way communication transmitting / receiving section and out of the wide area one-way communication area. Is transmitted to the control station through the first cell base station through the first cell base station. When the control station receives the terminal information, the control station sends a message addressed to the mobile communication terminal to the mobile communication terminal to the first cell base station. , And is transmitted.

[0013] In the mobile communication system according to the present invention, when the mobile communication terminal is located in the wide area and the two-way communication service area, the start-up signal from the wide-area base station activates the transmitting / receiving unit for two-way communication. Data reception is performed through the cell base station. More specifically, when the mobile communication terminal is registered in the cell base station, the mobile communication terminal enters a data reception waiting state, and intermittently receives a message addressed to itself transmitted from the system control device 109 through the registered cell base station.

Further, when the mobile communication terminal exists outside the wide area and within the two-way communication service area,
The mobile communication terminal detects that the mobile communication terminal is out of the wide area area, and transmits information outside the service area to the system management side using the two-way communication system. In this case, the system management uses the bidirectional communication system to transmit the message as described above without transmitting the activation signal.

Further, when the mobile communication terminal exists within the wide area and outside the two-way communication service area, that is, in the above-described embodiment, if the mobile terminal does not respond even if the activation signal is transmitted a predetermined number of times. The data is transmitted to the mobile communication terminal using the wide area selective calling system.

With this configuration, data transmission can be performed smoothly, and transmission efficiency and reliability can be improved. Furthermore, the mobile communication terminal waits for an activation signal by the wide-area selective call receiving unit that consumes less power, and after receiving the activation signal, activates the transmitting and receiving unit for bidirectional communication that consumes a large amount of power. Can be suppressed.

[0017]

FIG. 1 is a schematic system configuration diagram showing an embodiment of a communication system according to the present invention. This communication system includes a wide area base station 102 forming a wide area wireless area 101 and a plurality of cell base stations (CS) 1 forming a narrow area wireless area (cell) 103 arranged in a cell.
04 and a mobile terminal carried by the user. The communicable area includes a wireless area in which the wide area wireless area 101 and the service area of the plurality of cells 103 overlap, and a wireless area in which only one of them is provided. For example, a position 105A in the figure exists in an overlapping area between the wide area wireless area 101 and the cell service area, and a position 105B exists outside the wide area wireless area 101 but in the cell of the nearest cell base station 104.

The communication system is a system management center 1
06. System management center 106
Is a system that supervises and controls the wide area base station 102 and the plurality of cell base stations 103; a two-way communication control device 107 (for example, a digital mobile phone system) connected to the plurality of cell base stations 103; It has a wide area selective call control device 108 (for example, a paging system) connected to the wide area base station 102, a system control device 109 for controlling them, and a storage device 110 for storing data received from each terminal. The system management center 106 can be further connected to a communication partner terminal via the public network 111.

As will be described in detail later, the mobile terminal MT
Has a so-called pager receiving unit and a cellular transmitting / receiving unit. Upon receiving the activation signal from the wide area base station 102,
After power is supplied to the cellular transmitting / receiving unit and the location is registered with the nearest cell base station through the cellular transmitting / receiving unit, the cellular phone enters the intermittent reception state. If a message addressed to the mobile terminal is stored in the system management center 106, the data is transferred from the system management center 106 to the mobile terminal MT through the two-way communication system.

FIG. 2 is a block diagram showing an internal circuit configuration of an example of the mobile communication device according to the present embodiment. An antenna 201 for receiving a radio signal from the wide area base station 102 is connected to a wide area receiving section 202, and an antenna 203 for communicating with the cell base station 104 is connected to a receiving section 205 and a transmitting section via an antenna switch (or duplexer) 204. 206. Wide-area receiving section 202 demodulates a radio signal from wide-area base station 102 and receives received electric field strength R
Output to the processor 207 together with the SSIPG. Also, the receiving unit 205 demodulates a radio signal from the cell base station 104 and outputs the demodulated signal to the processor 207 together with the received electric field strength RSSICL. The transmission unit 206 modulates and amplifies the power of the transmission signal TCL from the processor 207 and outputs the result to the antenna 203 via the antenna switch 204.

The processor 207 performs a decoder function of decoding the wide-area reception signal RPG and performing synchronization processing, a function of determining whether the data is outside or within the wide area from the error rate of the received data, and a channel control of the transmission signal TCL and the reception signal RCL. This implements a channel codec function to be performed, and other functions and communication control described later. The memory 208 connected to the processor 207 stores a self-addressed message received from the wide area base station 102, a message or data input by a user, fixed data used for creating a reply indicating that the message has been received, and the like. Further, the processor 207 includes a display unit 209 such as a liquid crystal, an operation unit 210, a notification unit 211 such as a speaker,
And an external data input / output unit 212 are connected. The display unit 209 displays, according to a user operation of the operation unit 210,
You will see incoming messages and any other messages you need,
The notification unit 211 notifies that a call has occurred. When performing bidirectional communication through the cell base station, received data and transmission data are exchanged via the input / output unit 212. For example, in the case of a wireless telephone, reception and transmission are performed by a speaker and a microphone.

A power supply unit 213 includes a battery, and is controlled by the processor 207 or operated by a power switch 214.
N / OFF. The power supply unit 213 has a different power supply voltage VCC.
1 and VCC2 (here, VCC1 <VCC2), and the power supply voltage VCC1 is supplied to the wide area receiving section 202 through the power control section 215.
The power supply voltage VCC2 is supplied to the receiving unit 205 and the transmitting unit 206 for bidirectional communication through the power control unit 216. The power control unit 215 includes the processor 207
ON / OFF of the intermittent reception of the wide area receiver 202 under the control of
The power supply control unit 216 also controls the intermittent reception ON / OF of the reception unit 205 under the control of the processor 207.
The F control and the transmission power control of the transmission unit 206 are respectively performed. The wide-area receiver 202 does not require location registration and channel switching as in bidirectional transmission / reception, and performs intermittent reception operation at a relatively low voltage. Can be operated. Therefore, the wide area receiving unit 202 can operate for a long time.

Next, an embodiment of the data transmission method in the mobile communication system will be described with reference to FIGS.

FIG. 3 is a flowchart showing a control flow of the mobile communication terminal in one embodiment of the data transmission method according to the present invention. When the switch 214 is closed, the power supply unit 213 supplies the power supply voltage VCC1 to the power supply control unit 215, and the power supply control unit 215 supplies power to the wide area reception unit 202 to start the intermittent reception operation (S301). More specifically, when the processor 207 performs a synchronization process according to a received signal from the wide area base station 102 and detects a signal including a message addressed to itself, that is, a timing of the own group, the processor 207 outputs an intermittent control signal to the power control unit 215, The wide area receiving unit 202 is set to the intermittent receiving state. Wide area receiver 202
Is in the intermittent reception state at all times, and the wide area base station 1
02 can be received.

When receiving the own group signal, the processor 207 checks whether the own apparatus is within or outside the wide area 101 using the error rate of the received signal (S30).
2). If it is determined that the mobile phone is within the wide area 101 (YES in S302), if it is called by itself (S302).
It is checked whether or not the message includes a predetermined activation signal (YES in 303) (S304). If the activation signal is not included (NO in S304), the processor 207 drives the notification unit 211 to notify the user of the occurrence of the call, and operates the operation unit 210 to determine the content of the received message if the user considers it necessary. Is displayed on the display unit 209 (S305). Hereinafter, the wide area intermittent reception operation S301 to S3
By repeating step 05, the wide area receiving section 202 can receive data from the wide area base station 102. The determination as to whether the received signal is located in the wide area 101 may be performed by measuring the field strength RSSI of the received signal.

When the start message is included in the received message (YES in S 304), processor 207 outputs a control signal to power supply control section 216, and the power supply voltage is supplied from power supply control section 216 so that bidirectional communication is performed. Receiving unit 20 for
5 and the transmitting unit 206 are excited to start communication with the cell base station 104 (S306). First, the processor 20
7 generates a response signal indicating that the activation signal has been received, and transmits a location registration signal including the response signal from the transmission unit 206 to the nearest cell base station 104 (S307). The cell base station 104 that has received the location registration information performs location registration of the mobile communication terminal.

When the location is registered, the mobile communication terminal performs intermittent reception of data from the cell base station whose location has been registered by the receiving unit 205 (S308). More specifically, if the mobile communication terminal is in the same cell (YES in S309), unless there is a transmission request (NO in S310), receiving section 205 causes cell registered in position according to the intermittent reception power control of power supply control section 216. A signal (a message addressed to the mobile terminal) from the base station 104 is intermittently received (S308). In the case of transmitting data (YES in S310), the user operates the operation unit 210 to read out a fixed phrase or other data stored in the memory 208 and transmit the transmission signal T.
The data is transmitted to the transmission unit 206 as a CL and transmitted to the cell base station whose position has been registered (S311). If the mobile communication terminal moves to an adjacent cell (NO in S309), location registration is performed for the cell base station as described above (S31).
2), repeat the above processing (S308 to S31)
3). In this manner, the mobile communication terminal is connected to the wide area base station 10.
Receiving data through cell base station 104 instead of 2,
Data can be transmitted as needed. When ending communication with the cell base station (YES in S313),
A communication end notification is transmitted (S314), and the process returns to the intermittent reception mode (S301) in the wide area.

When the mobile terminal is located outside the wide area 101 (NO in S302), the processor 2
Reference numeral 07 outputs a control signal to the power control unit 216, and when the power supply voltage is supplied from the power control unit 216, the receiving unit 205 and the transmitting unit 206 for bidirectional communication are excited, and communication with the cell base station 104 is performed. It is started (S315). The processor 207 generates out-of-service area information indicating that the service is out of the service area of the wide area selective calling system,
The location registration signal including the out-of-service area information is transmitted from the transmission unit 206 to the nearest cell base station 104 (S3).
16). Then, by the above-described intermittent reception, the mobile terminal enters a message reception reception state addressed to the mobile terminal (S308).

FIG. 4 is a flowchart showing a system management control flow in this embodiment. When a call to a certain mobile terminal occurs (YES in S401), the system controller 109 checks whether or not information outside the service area has been received (S402). If the out-of-service area information is not received (NO in S402), it indicates that the mobile terminal is within the area of the wide area 101, so that the wide area base station 102 Sends an activation signal to the terminal (S403). When the mobile terminal does not return a response signal to the activation signal (S4
04 (NO), a start signal is transmitted a predetermined number N (S
405, S406).

If the response signal is not received even after transmitting the activation signal N times (YES in S405), it is determined that the mobile terminal is located within the wide area 101 but outside the two-way communication service area. Then, the data addressed to the mobile terminal is transmitted using the wide area selective calling system (S
407). When all data has been transmitted to the mobile terminal, the system control device 109 updates the storage device 110 (S408).

On the other hand, if the out-of-service area information is received (YES in S 402), it indicates that the mobile terminal is out of the area of the wide area 101, so that the start signal is transmitted from the area base station 102. Instead, the terminal information of the mobile terminal is registered in the storage device 110 (S40).
9). Subsequently, the system control device 109 stores the storage device 11
0 is checked to see if there is a message addressed to the mobile terminal (S410). If the message is stored (YES in S410), the message data is transmitted through the cell base station whose location has been registered. The data is transmitted to the mobile terminal (S411).

As described above, in the mobile communication system according to the present invention, when the mobile terminal is located within the wide area and the two-way communication service area, the transmission / reception unit for two-way communication is activated by the activation signal from the wide-area base station. It is activated and data reception is performed through the cell base station. More specifically, when the mobile communication terminal is registered in the cell base station, the mobile communication terminal enters a data reception waiting state, and intermittently receives a message addressed to itself transmitted from the system control device 109 through the registered cell base station.

When the mobile terminal is outside the wide area and within the two-way communication service area, it is detected that the mobile terminal is outside the wide area and the out-of-service information is used by the two-way communication system. To the system management side. In this case, the system management uses the bidirectional communication system to transmit the message as described above without transmitting the activation signal.

Further, when the mobile terminal exists within the wide area and outside the two-way communication service area, that is, in the above-described embodiment, if the mobile terminal does not respond even after transmitting the activation signal a predetermined number of times, The data is transmitted to the mobile terminal using the wide area selective calling system.

With this configuration, data transmission can be performed smoothly, and transmission efficiency and reliability can be improved. Furthermore, the mobile terminal waits for the activation signal by the wide area selective call receiving unit that consumes less power, and after receiving the activation signal, activates the transmitting and receiving unit for bidirectional communication that consumes a large amount of power. can do.

[Brief description of the drawings]

FIG. 1 is a schematic system configuration diagram showing an embodiment of a communication system according to the present invention.

FIG. 2 is a block diagram illustrating an internal circuit configuration of an example of the mobile communication device according to the embodiment.

FIG. 3 is a flowchart illustrating a control flow of a mobile terminal in one embodiment of a data transmission method according to the present invention.

FIG. 4 is a flowchart illustrating a control flow of a system control device according to the present embodiment.

[Explanation of symbols]

 Reference Signs List 101 Wide area wireless area 102 Wide area base station 103 Cell 104 Cell base station 105A, 105B Location of mobile communication device 106 System management center 107 Two-way communication control device 108 Wide area selection call control device 109 System control device 110 Storage device 111 Public network 201 Wide-area receiving antenna 202 Wide-area receiving section 203 Bidirectional receiving antenna 204 Antenna switch 205 Receiving section 206 Transmitting section 207 Processor 208 Memory 209 Display section 210 Operation section 211 Notification section 212 Input / output section 213 Power supply section 214 Switch 215 Power supply control section 216 Power control unit

Continuation of the front page (72) Inventor Shinya Usami 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (56) References JP-A-3-32236 (JP, A) JP-A-64-51729 JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) H04B 7/24-7/26 H04Q 7/00-7/38

Claims (6)

(57) [Claims] 1. A wide area base station forming a wide area unidirectional communication area, a plurality of cell base stations forming a cellular bidirectional communication area, a mobile communication terminal, the wide area base station and the plurality of cell bases A mobile communication system comprising: a control station for controlling a mobile station; and a control station for controlling a mobile station. The mobile communication terminal comprises: a receiving unit for receiving a radio signal from the wide area base station; Transmitting / receiving means for performing bidirectional communication with a first cell base station forming an area; determining means for determining whether a radio signal from the wide area base station can be received; and When it is determined that the radio signal is receivable, when the start signal is received from the wide area base station, the transmitting and receiving means is started and a response signal to the start signal is transmitted to the first cell base station, Said When the radio signal from frequency base station is determined to be unreceivable transmits terminal information indicating a wide-way communication area out of service by activating the transceiver unit to the first cell base station, further,
Communication control means for setting the transmission / reception means in a standby state for waiting for a signal from the first cell base station; wherein the control station stores a message addressed to the mobile communication terminal; and the mobile communication terminal. Is present in the wide area one-way communication area, the start signal transmission control means for transmitting the start signal to the mobile communication terminal through the wide area base station, and transmitting the response signal through the first cell base station. Transmitting a message stored in the storage means to the mobile communication terminal through the first cell base station when receiving from the communication terminal, and, when the mobile communication terminal is outside the wide area unidirectional communication area, The message stored in the storage means is transmitted to the first device without transmitting a signal.
And a transmission control means for transmitting to the mobile communication terminal through a cell base station. 2. The mobile communication system according to claim 1, wherein said activation signal transmission control means transmits said activation signal a predetermined number of times when said response signal is not received. 3. The transmission control means transmits the message to the mobile communication terminal through the wide area base station if the response signal is not received even after transmitting the activation signal for the predetermined number of times. The mobile communication system according to claim 2, wherein the communication control means of the mobile communication terminal always keeps the reception means in an intermittent reception state. 4. A wide area base forming a wide area unidirectional communication area.
A plurality of cells forming a cellular bidirectional communication area
Cell base station and a two-way communication area formed by the first cell base station.
A mobile communication terminal located in
A mobile station comprising a number of cell base stations and a control station controlling the number of cell base stations
In the data transmission method in the communication system, the control station stores data addressed to the mobile communication terminal.
Then, the activation signal addressed to the mobile communication terminal is transmitted to the wide area base station.
The mobile communication terminal transmits a start signal from the wide area base station.
Activate the transmitter / receiver for bidirectional communication in response to the response signal
Is transmitted to the control station through the first cell base station. When the control station receives the response signal,
To the mobile communication terminal through the first cell base station.
The mobile communication terminal transmits the message to the first cell base.
Intermittent reception from local officeAnd The mobile communication terminal transmits a radio signal from the wide area base station.
If it is determined that reception is not possible, the two-way communication
Activate the trust transmitter / receiver and go out of the wide area one-way communication area
Indicating the terminal information through the first cell base station to the control station
Send to When the control station receives the terminal information, the control station
A message addressed to the communication terminal to the mobile communication terminal.
Transmitting through the base station, A data transmission method, comprising: 5. The mobile communication terminal according to claim 1, wherein the mobile communication terminal operates at relatively low power, and intermittently receives a radio signal from the wide area base station; And a transmitting unit and a receiving unit for performing bidirectional communication with a first cell base station forming a bidirectional communication area in which the mobile communication terminal exists, and operating from the wide area base station. Determining means for determining whether a wireless signal from the wide area base station is receivable; and, when it is determined that the wireless signal from the wide area base station is receivable, the transmitting unit when receiving an activation signal from the wide area base station. And transmits a response signal to the activation signal to the first cell base station, and when it is determined that a radio signal from the wide area base station cannot be received, activates the transmission unit to perform wide area communication. One-way communication Communication control means for transmitting terminal information indicating out-of-service to the first cell base station, and setting the receiving unit to an intermittent reception standby state for waiting for a signal from the first cell base station. Mobile communication terminal. 6. A mobile communication device in a mobile communication system, comprising: a wide area receiving unit that operates at relatively low power and intermittently receives a radio signal from a wide area base station forming a wide area selective call communication area; A transmitter and a receiver that operate with greater power than the wide area receiving section and perform bidirectional communication with a cell base station that forms a cellular bidirectional communication area, and a radio signal from the wide area base station is Determining means for determining whether or not receivable; and, when it is determined that the radio signal from the wide area base station is receivable, activating the transmitting unit when receiving an activation signal from the wide area base station. A response signal to the activation signal is transmitted to the cell base station, and when it is determined that a radio signal from the wide area base station cannot be received, the transmission unit is activated to activate the wide area selective call communication area. It transmits the terminal information to the cell base station indicating the further mobile communication device comprising a communication control unit, that consists of the reception unit to the intermittent reception standby state to wait for a signal from the cell base station.