JP2002044009A - Radio mobile device and communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a radio mobile device to start communication, setting up synchronization and decreasing power consumption when it is able to start communication. SOLUTION: A second radio set 104 such as a wrist watch is so set as to communicate with a first radio set 103 such as PDA or the like. When the second radio set 104 is not able to make communication with the first radio set 103, it is judged by carrying out carrier detection of small power consumption whether the radio set 104 is able to communicate with the radio set 103 or not. When it is found that the radio set 104 is able to communicate with the radio set 103, the radio set 104 receives signals continuously from the radio set 103 to establish the intermittent sending/receiving synchronization with the radio set 103 and starts communicating with the radio set 103.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio mobile station for communicating with another radio station and a communication system including a plurality of radio mobile stations. The present invention relates to a wireless mobile device that establishes synchronization and starts communication, and a communication system including a plurality of the wireless mobile devices.

[0002]

2. Description of the Related Art As a conventional communication system, for example,
2. Description of the Related Art A communication system including a wireless mobile device and a fixed connection device disclosed in Japanese Patent Application Laid-Open No. 5-252093 is known. In this communication system, the fixed connection device periodically transmits an annunciation signal from the transmission period setting timer by a fixed-slot time slot, and the wireless mobile device first transmits the annunciation signal in a continuous reception mode in which the operation time of the receiving unit is lengthened. Upon receiving, the built-in receiving period setting timer is synchronized, and thereafter, the receiving unit is driven during a fixed period time slot as a non-continuous receiving mode in which synchronization is performed each time a broadcast signal is received. When synchronization is lost, the mode is switched to the continuous reception mode. As described above, the conventional communication system operates in the continuous reception mode when communication cannot be performed, and establishes synchronization and starts communication when communication becomes possible.

[0003]

However, according to the above-mentioned prior art, when a state in which communication cannot be performed easily occurs, for example, when the method is applied to communication between mobile stations using weak radio waves, the state in which communication cannot be performed is considered. During this period, the continuous reception mode is set, so that there is a problem that power consumption increases.

The present invention has been made in view of the above, and it is an object of the present invention to establish synchronization and start communication when communication becomes possible while reducing power consumption.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, a wireless mobile device according to the present invention cannot communicate with another wireless station in a wireless mobile device communicating with another wireless station. In this case, carrier detection means that performs low power consumption carrier detection to determine whether communication with another wireless station is possible, and that the carrier detection means determines that communication with another wireless station is possible And a synchronization establishing means for continuously receiving and establishing communication synchronization with another wireless station in the case where the communication is performed.

[0006] According to this radio mobile station, the detecting means performs low power consumption carrier detection when communication with another radio station is not possible, and determines whether communication with the other radio station is possible. In the determination, when the carrier establishment means determines that the communication with another wireless station is possible, the synchronization establishing means continuously performs the reception to establish the synchronization of the communication with the other wireless station. In other words, during a state where communication is not possible, instead of performing continuous reception, carrier detection with lower power consumption is performed, and after a state where communication is possible, continuous reception is performed to synchronize communication. Establish.

Here, the other radio station may be a mobile station that communicates with a fixed station. As a result, the present invention can be applied to a wireless mobile device such as a wrist portable information device that communicates with a mobile device such as a PDA that communicates with a fixed station using a weak radio wave or the like.

Further, a communication system according to the present invention comprises a communication system having a plurality of wireless mobile devices that communicate with each other, when at least one of the plurality of wireless mobile devices cannot communicate with each other. Carrier detecting means for detecting whether low-power-consumption carriers can communicate with each other, and receiving continuously when the carrier detecting means determines that mutual communication is possible. And a synchronization establishing means for establishing communication synchronization between them.

According to this communication system, in at least one of the plurality of wireless mobile devices, when the communication between the mobile devices cannot be performed, the detection unit can detect the carrier with low power consumption and perform the communication between the mobile devices. It is determined whether or not the synchronization is established. When the carrier detection unit determines that the communication between the carriers is possible, the synchronization is established, and the synchronization is established. That is, in at least one of the plurality of wireless mobile devices, during a state in which communication is not possible, instead of performing continuous reception, carrier detection with lower power consumption is performed, and after a state in which communication is possible, Continuous reception is performed to establish communication synchronization.

[0010] Here, at least one of the plurality of wireless mobile devices is provided.
Alternatively, communication with a fixed station may be performed. Thus, a wireless mobile device such as a PDA that performs communication with a fixed station can be provided.
The present invention can be applied to a communication system including a wireless mobile device such as a wrist portable information device that performs communication using a weak radio wave or the like with the wireless mobile device.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The present invention is not limited by the present embodiment.

FIG. 1 is an explanatory diagram showing a configuration of a communication system according to one embodiment of the present invention. The communication system according to the present embodiment includes a first wireless device 103 that communicates with a fixed station 101 such as NTT or an artificial satellite 102, and a second wireless device 104 that communicates with the first wireless device 103. Have. The first wireless device 103 is, for example, a PDA, PH
S, mobile phone, pager, etc.
Is an arm portable information device such as a wristwatch, for example.

The first radio 103 and the second radio 104
In order to reduce power consumption, communication is performed by intermittent transmission / reception by operating each transmission / reception unit intermittently at a predetermined cycle. First wireless device 103 and second wireless device 10
The communication with No. 4 is performed by a weak radio wave of specific low power, etc.
For example, the first wireless device 103 transmits data received from the fixed station 101 to the second wireless device 104, and the second wireless device 1
It is used for updating the data held by the 04.

FIG. 2 is a functional block diagram showing a configuration of the first wireless device 103 according to the embodiment shown in FIG. The first wireless device 103 includes a fixed station transmitting unit 201 that transmits data to the fixed station 101, a fixed station receiving unit 202 that receives data from the fixed station 101, and a fixed station 101.
Incoming detection unit 203 that detects that there is an incoming call from
A first radio receiver 204 for receiving data from the second radio 104; a first radio transmitter 205 for transmitting data to the second radio 104;
2, a memory 206 for storing the data received, an input unit 207 for the user to perform various inputs, and a transmission / reception period setting timer for setting the period of intermittent transmission / reception (intermittent transmission / reception) with the second wireless device 104 208 and a control unit 209 for controlling these units.

The control unit 209 includes a transmission / reception cycle timer 20.
The first radio receiver 204 and the first radio transmitter 205 are controlled according to the intermittent transmission / reception cycle set in step 8 and the second
Intermittent transmission and reception with the wireless device 104 are performed. Fixed station receiving unit 20
2 receives data from the fixed station 101,
When 03 detects an incoming call, the control unit 209 stores the received data in the memory 206, controls the first wireless device transmitting unit 205, and transmits the received data to the second wireless device 104.

FIG. 3 is a functional block diagram showing the configuration of the second wireless device 104 according to this embodiment shown in FIG. The second wireless device 104 includes a second wireless device transmitting unit 301 that transmits data to the first wireless device 103 and the first wireless device 10.
A second radio receiver 302 for receiving data from
A carrier detecting unit 303 for detecting a carrier from the first wireless device 103; a synchronization establishing program storage memory 304 storing a synchronization establishing program for establishing intermittent transmission / reception synchronization with the first wireless device 103; A memory 305 for storing data received by the unit 302, an input unit 306 for a user to make an input, and a control unit 307 for controlling these units are provided.

The second radio receiver 302 is connected to the first radio 10.
3 and the carrier detection unit 303 receives the data from the first
A carrier from the wireless device 103 is detected. Control unit 307
When the carrier detection unit 303 detects a carrier in a state where communication with the first wireless device 103 is not performed, that is, when communication with the first wireless device 103 becomes possible, the synchronization establishment program is stored. According to the synchronization establishment program stored in the memory 304, the intermittent transmission / reception synchronization with the first wireless device 103 is established, and communication is started. Note that the control unit 307 embodies the detecting unit and the synchronization establishing unit according to the present invention.

In the above configuration, the operation of the present embodiment will be described with reference to FIGS. FIG. 4 is a flowchart showing a flow of the operation of the first wireless device 103 according to the present embodiment. Control unit 209 of first wireless device 103
When the power is turned on, first, the fixed station receiving unit 202 is driven to perform an operation of receiving data from the fixed station 101 (S401). Next, the first wireless device transmitting unit 205 drives the first wireless device receiving unit 204 to perform a transmitting / receiving operation with respect to the second wireless device 104 (S402). This transmission / reception operation
For example, the DUTY
50%, only the carrier is transmitted.

Next, it is determined whether or not the power of the own device is turned off (S403). If the power is turned off, the driving of each unit is stopped (S407), and the operation ends. On the other hand, if the power has not been turned off, it is determined whether a synchronization establishment request signal has been received from the second wireless device 104 (S40).
4). If the synchronization establishment request signal has not been received, the process returns to step S401, and if the synchronization establishment request signal has been received, a transmission / reception timer operation with the second wireless device 104 is performed (S405). In the transmission / reception timer operation, intermittent transmission / reception of data is performed in a shorter cycle than before receiving the synchronization establishment request signal. Then, it is determined whether or not the communication with the second wireless device 104 is out of synchronization (S406). When the communication is out of synchronization, the process returns to step S401. to continue.

FIG. 5 is a flowchart showing the flow of the operation of the second wireless device 104 according to this embodiment. Second
When the power is turned on, the control unit 307 of the wireless device 104 first performs low power consumption carrier detection by the carrier detection unit 303 (S501). Then, it is determined whether a carrier has been detected, that is, whether communication with the first wireless device 103 is possible (S502). If a carrier has not been detected, it is determined that communication is not possible due to reasons such as radio waves not reaching due to the positional relationship with the first wireless device 103, and the process returns to step S501 to continue carrier detection.

On the other hand, if a carrier is detected, the first
It determines that communication with the wireless device 103 has become possible, and controls the second wireless device transmitting unit 301 to transmit a synchronization establishment request signal for requesting the first wireless device 103 to establish synchronization (S
501), the second radio receiver 302 is continuously driven to perform continuous reception (S504). Next, the first wireless device 10
It is determined whether the intermittent transmission / reception synchronization with No. 3 has been established (S505). If the synchronization has not been established, the process returns to step S504 to continue the continuous reception. (Transmission / reception timer operation) (S506). Next, it is determined whether or not the synchronization has been lost (S507).
Returning to step 501, if synchronization is not lost, step S
Returning to 506, intermittent transmission and reception are continued.

FIG. 6 is a timing chart showing the operation of the communication system according to the present embodiment. In the operation of this communication system, first, the first radio 103
Transmission and reception are performed at a duty of 50% at a relatively long cycle (601 in the figure). In this case, data and the like received from the fixed station 101 are not transmitted, and only the carrier is transmitted. On the other hand, the second wireless device 104 performs carrier detection to determine whether the first wireless device 103 is in a range where data communication is possible (602 in the figure). This carrier detection is performed at a frequency shorter than the transmission time of one cycle of the first wireless device 103,
In addition, the operation is performed with a small DUTY to save power.

When detecting the carrier, the second wireless device 104 transmits a synchronization establishment request signal (603 in the figure) and performs continuous reception (604 in the figure). The first wireless device 103
After receiving the synchronization establishment request signal from the second wireless device 104, transmission / reception is repeated at a faster cycle by a transmission / reception timer operation (605 in the figure). When receiving the data start signal twice from the first wireless device 103, the second wireless device 104 determines that synchronization has been established, shifts to a transmission / reception timer operation, and performs data communication (606 in the figure).

After that, if the second wireless device 104 fails to receive the data start signal from the first wireless device 103 twice, the second wireless device 104 performs communication for the reason that the first wireless device 103 has moved out of the communicable area. It is determined that it has become impossible, and the operation returns to the above-described carrier detection operation state (60 in the figure).
7). On the other hand, if the first wireless device 103 fails to receive the data from the second wireless device 104 twice, it returns to the state where only the carrier is transmitted at a relatively long cycle as described above (608 in the figure). When the second wireless device 104 detects a carrier again, it outputs a synchronization establishment request signal (609 in the figure),
Restart the transmission / reception timer operation. Here, the second wireless device 1
It is determined whether or not the data of the fourth wireless device 104 is the latest data, and the data of the second wireless device 104 is updated.

As described above, according to the present embodiment,
When the second wireless device 104 cannot communicate with the first wireless device 103, it does not continue the continuous reception, but detects the carrier with lower power consumption, and after the communication becomes possible, Since reception is performed and intermittent transmission / reception synchronization is established, even when communication is temporarily disabled, it is possible to wait for communication to be enabled while suppressing power consumption. The communication can be resumed by establishing synchronization. In the present embodiment, the first wireless device 103 and the second wireless device 104 are likely to be in a state in which they cannot communicate with each other.
This is particularly effective when a large power supply cannot be provided.

In the above-described embodiment, the P which performs communication with the fixed station 101 or the like as the first wireless device 103 is used.
Although a wireless mobile device such as a DA has been described as an example, the first wireless device 103
May be fixed, and the fixed station 10
It may not perform communication with the first or the like. For example, it may be provided in a refrigerator and inform the second wireless device 104 of information on the contents of the refrigerator. Further, there may be a plurality of first wireless devices and / or second wireless devices.

[0027]

As described above, the wireless mobile device of the present invention can perform communication by performing carrier detection with lower power consumption, instead of continuously receiving data while communication cannot be performed. After the state, the reception is continuously performed to establish communication synchronization. Therefore, when communication becomes possible while reducing power consumption, synchronization can be established and communication can be started.

Further, in the wireless mobile device of the present invention, since the other wireless station is a mobile device that communicates with the fixed station, a weak radio wave or the like is transmitted between the mobile station and a mobile device such as a PDA that communicates with the fixed station. The present invention can be applied to a wireless mobile device such as an arm portable information device that performs communication according to.

Further, in the communication system of the present invention, at least one of the plurality of radio mobile devices performs carrier detection with lower power consumption instead of continuously receiving signals while communication is not possible. After the communication is enabled, the reception is continuously performed to establish communication synchronization. Therefore, when communication becomes possible while reducing power consumption, communication is established and communication is started. be able to.

Further, in the communication system according to the present invention, at least one of the plurality of wireless mobile stations communicates with the fixed station. The present invention can be applied to a communication system including a wireless mobile device such as a wrist portable information device that performs communication by a weak radio wave or the like with the mobile device.

[Brief description of the drawings]

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

FIG. 2 is a functional block diagram illustrating a configuration of a first wireless device according to the present embodiment illustrated in FIG. 1;

FIG. 3 is a functional block diagram illustrating a configuration of a second wireless device according to the present embodiment illustrated in FIG. 1;

FIG. 4 is a flowchart showing a flow of an operation of the first wireless device according to the embodiment.

FIG. 5 is a flowchart showing a flow of an operation of the second wireless device according to the embodiment.

FIG. 6 is a timing chart showing an operation of the communication system according to the exemplary embodiment;

[Explanation of symbols]

 Reference Signs List 101 fixed station 102 artificial satellite 103 first wireless device 104 second wireless device 201 fixed station transmitting unit 202 fixed station receiving unit 203 incoming call detecting unit 204 first wireless unit receiving unit 205 first wireless unit transmitting unit 206, 305 memory 207, 306 Input unit 208 Transmission / reception cycle setting timer 209, 307 Control unit 301 Second radio transmission unit 302 Second radio reception unit 303 Carrier detection unit 304 Synchronization establishment program storage memory

Claims (4)

[Claims] In a wireless mobile device that communicates with another wireless station, when communication with the other wireless station cannot be performed, low-power-consumption carrier detection is performed to perform communication with the other wireless station. Carrier detecting means for determining whether or not the communication is possible, and when the carrier detecting means determines that communication with the other wireless station is possible, continuously performs reception and performs communication with the other wireless station. And a synchronization establishing means for establishing synchronization of the communication. 2. The wireless mobile device according to claim 1, wherein the other wireless station is a mobile device that communicates with a fixed station. 3. A communication system including a plurality of wireless mobile devices that communicate with each other, wherein at least one of the plurality of wireless mobile devices has a low power consumption carrier when the mutual communication cannot be performed. Carrier detecting means for performing detection to determine whether or not the mutual communication is possible, and performing continuous reception when the carrier detecting means determines that the mutual communication is possible. A communication establishment means for establishing communication synchronization between the communication systems. 4. The communication system according to claim 3, wherein at least one of the plurality of wireless mobile devices performs communication with a fixed station.