JP2842423B2 - Mobile communication system and data transmission method - 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 and a data transmission method 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]

However, in the above-mentioned conventional mobile communication 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 notifies the caller. This method is effective only in the area of the wide area selective calling radio area, and is not sufficient in terms of efficiency and reliability as a two-way communication system.

An object of the present invention is 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.

[0006]

SUMMARY OF THE INVENTION A mobile communication system according to the present invention includes a wide area base station forming a wide area unidirectional communication area, a plurality of cell base stations forming a cellular bidirectional communication area, and a mobile communication system. The mobile communication terminal, comprising: a terminal, a control station that controls the wide area base station and the plurality of cell base stations, wherein the mobile communication terminal receives a radio signal from the wide area base station; Transmitting and receiving means for performing bidirectional communication with a first cell base station forming a bidirectional communication area in which a communication terminal exists, and generating wide-area terminal information indicating a reception state of a radio signal from the wide-area base station First
Detecting means, second detecting means for generating cell terminal information indicating a reception state of a radio signal from the first cell base station, and transmitting and receiving the wide area terminal information and the cell terminal information to the first cell base station by the transmitting / receiving means. Communication control means for transmitting to a station, the control station further comprising: storage means for storing the wide area terminal information and cell terminal information of the mobile terminal received by the first cell base station; Selecting means for selecting a base station more suitable for data transmission among the wide area base station and the first cell base station by comparing the terminal information and the cell terminal information, and when there is data addressed to the mobile terminal, Transmission control means for transmitting the data to the mobile terminal through the selected base station.

Further, in the data transmission method according to the present invention, the first reception field strength information of the radio signal from the wide area base station received by the mobile communication terminal and the second reception field strength information of the radio signal from the first cell base station are provided. Receiving the received field strength information from the mobile communication terminal through the first cell base station and storing the first received field strength information and the second received field strength information of the mobile terminal received by the first cell base station And comparing the first received electric field strength information and the second received electric field strength information to select a base station having a larger received electric field strength among the wide area base station and the first cell base station; Transmitting data to the mobile terminal through the selected base station when there is data addressed to the mobile terminal.

[0008] With this configuration, two systems, a selective calling system for a wide area wireless zone and a two-way data transmission system comprising a cellular wireless area, are used.
By transmitting terminal information including the electric field information of the terminal in each system to the system side through the bidirectional data transmission system, it is possible to select the optimal system for data transmission, enabling reliable and efficient data transmission Becomes

[0009]

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 above 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 section and a cellular transmitting / receiving section, receives a radio signal from the wide area base station 102 and a radio signal from the nearest cell base station 104, measures the respective electric field strengths, and The information can be included in the service area information and transmitted to the cell base station as terminal information. Using the received electric field information of the mobile terminal received through the two-way communication control device 107, the system control device 109 determines which of the two-way communication system and the wide area selective calling system is suitable for data transmission, and To transmit data to mobile terminals through this 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 206 via an antenna switch 204. ing.
Wide-area receiving section 202 demodulates a radio signal from wide-area base station 102 and outputs the demodulated radio signal to processor 207 together with the received field strength RSSIPG. Also, the receiving unit 205 is a cell base station 1
Demodulation of the radio signal from the receiver 04 and its received field strength RSSI
Output to processor 207 together with CL. Transmission unit 206
Is transmitted to the antenna 203 via the antenna switch 204 after modulating and amplifying the power of the transmission signal TCL from the processor 207.

The processor 207 has a decoder function of decoding the wide-area reception signal RPG and performing a synchronization process, and the wide-area reception unit 202.
And the received electric field strength R input from the receiving unit 205, respectively.
It implements a function of generating service area information from SSIPG and RSSICL, a channel codec function of performing channel control of a transmission signal TCL and a reception signal RCL including service area information, 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 20 such as a liquid crystal.
9, an operation unit 210, a notification unit 211 such as a speaker, and an input / output unit 212 for external data are connected. Display 2
In 09, a received message and other necessary messages are displayed in accordance with a user operation of the operation unit 210, and the notification unit 211 notifies that a call has occurred. When performing two-way communication through a cell base station,
Received data and transmitted 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 receiving section 202 does not require location registration or channel switching as in bidirectional transmission / reception, and performs intermittent reception operation at a relatively low voltage. And can be operated with low power. Therefore, the wide area receiving unit 202 can operate for a long time.

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

FIG. 3 is a schematic diagram showing a process of generating terminal information in one embodiment of the data transmission method according to the present invention. The mobile terminal MT intermittently receives the selective call signal from the wide area base station 102, measures its received field strength RSSIPG, receives a control signal from the nearest cell base station 104 whose location has been similarly registered, and receives its received field strength. Measure RSSICL. In the processor 207, cellular electric field information SCLI is generated from the received electric field strength RSSICL of the cell (S
301), the received field strength RSSIPG of the wide area 101
, The wide area electric field information SPGI is generated (S30).
1). The service area information including the cellular electric field information SCLI is generated and transmitted from the transmitting unit 206 to the cell base station 104 whose position has been registered. Similarly, the service area information including the wide area electric field information SPGI has also been registered.
4 (S303).

The service area information including such terminal information is periodically transmitted from the mobile terminal to the nearest cell base station. The service area information received by the cell base station is transmitted to the bidirectional communication control device 107 together with the identification number of the mobile terminal.
Is transmitted to the system controller 109 via the storage device 11 as terminal information indicating the reception radio wave condition of the mobile terminal.
0 is stored.

FIG. 4 is a flowchart showing a control flow of the system control device according to this embodiment. First,
When the terminal information described above is received from a certain cell base station (S
401), the cellular electric field information SCLI and the wide area electric field information SPGI are stored in the storage device 110 (S402),
It is checked whether the data addressed to the mobile terminal is stored in the storage device 110 (S403). If there is no data addressed to the mobile terminal (NO in S403), the public network 11
1 to check whether data has been received (S
404) If received, store the data in storage device 110
(S405).

Next, the system controller 109 reads the cellular electric field information SCLI and the wide area electric field information SPGI of the mobile terminal from the storage device 110 (S406), and compares the magnitude of the received electric field strength (S407). That is, it is determined which system is suitable for data transmission. If the wide area electric field information SPGI is a larger value (YES in S407), since the received radio wave condition of the wide area 101 is good, the wide area selective call control device 108 is selected and the data addressed to the mobile terminal is transmitted. The data is transmitted to the mobile terminal through the wide area base station 102 (S408).
On the other hand, if the value of the cellular electric field information SCLI is a larger value (NO in S407), the bidirectional communication control device 107 is selected, and data addressed to the mobile terminal is transmitted to the mobile terminal through the cell base station whose location is registered. The data is transmitted (S409).

Thus, the bidirectional communication control device 10
7, the system controller 109 determines which of the two-way communication system and the wide area selective call system is suitable for data transmission, using the received electric field information of the mobile terminal received through Transmit data to Thus, data transmission can be performed smoothly, and transmission efficiency and reliability can be improved.

[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 schematic diagram showing a process of generating terminal information in one embodiment of the 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

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

Claims (5)

(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; first detecting means for generating wide-area terminal information indicating a reception state of a radio signal from the wide-area base station; Second detecting means for generating cell terminal information indicating a reception state of a radio signal from the first cell base station; and transmitting the wide area terminal information and the cell terminal information to the first cell base station by the transmitting / receiving means. A communication control unit, wherein the control station stores the wide area terminal information and the cell terminal information of the mobile terminal received by the first cell base station; and the wide area terminal information and the cell terminal. Comparing means for selecting information from among the wide area base station and the first cell base station to select a more suitable base station for data transmission; and selecting the selected base station when data destined for the mobile terminal exists. Transmission control means for transmitting the data to the mobile terminal through a station. 2. The wide area terminal information is an electric field strength of a radio signal received from the wide area base station, and the cell terminal information is an electric field strength of a radio signal received from the first cell base station. The mobile communication system according to claim 1, wherein 3. The mobile communication system according to claim 1, wherein the wide area terminal information and the cell terminal information are included in service area information and transmitted to the first cell base station. 4. A wide area base station forming a wide area unidirectional communication area, a plurality of cell base stations forming a cellular two-way communication area, and a two-way communication area formed by a first cell base station. A data transmission method in a mobile communication system, comprising: a mobile communication terminal; and a first reception field strength information of a radio signal from the wide area base station received by the mobile communication terminal and a radio signal from the first cell base station. Receiving the second reception field strength information of the signal from the mobile communication terminal through the first cell base station; and receiving the first reception field strength information and the second reception field of the mobile terminal received by the first cell base station. By storing strength information and comparing the first reception field strength information and the second reception field strength information, the reception field strength of the wide area base station and the first cell base station is larger. Selecting one of the base stations, and transmitting the data to the mobile terminal through the selected base station when there is data addressed to the mobile terminal. 5. A wide area selective calling system comprising one wide area, a two-way communication system comprising a plurality of cellular two-way communication areas, a wide area selective calling system and control for integrating and controlling said two-way communication system. A mobile communication terminal, the mobile communication terminal comprising: a wide-area reception field strength information of the received radio signal in the wide area; and a radio signal in a first two-way communication area where the mobile communication terminal is located. And the cell reception field strength information transmitted through the first two-way communication area, the control station, based on the wide area reception field strength information and the cell reception field strength information of the mobile communication terminal, the wide area selective call system and the A system having a higher received electric field strength is selected from the two-way communication system, and the data addressed to the mobile communication terminal is selected using the selected system. Mobile communication system for transmitting data to the mobile communication terminal, characterized in that.