JP2002171226A - Radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dealing method of a radio communication system capable of always realizing communication from a detector to a center. SOLUTION: A radio master device 5 retry-transmits a test signal to a radio slave device 6a at a prescribed time periodically, for example, once a day. In this case, the information of the transmitting time or the number of times of test is superimposed on the test signal. The radio master device 5 retry- transmits the test signal to the radio slave device 6a three times every two minutes on the first day, The radio slave device 6a is not able to receive the test signal three times due to any factor. The radio master device 6 transmits the test signal to the radio slave device 6a three times on the second day and the third day. The radio slave device 6a is not able to receive the test signal due to any factor on the second day or the third day in the same way as the first day. The radio master device 5 transmits the warning signal of communication abnormality to a center 2 after the lapse of a specific time of the counter of a timer control circuit 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication system for transmitting an alarm in conjunction with an alarm attached to a gas meter or the like, and more particularly to a radio communication system for periodically confirming communication in a radio section. is there.

[0002]

2. Description of the Related Art FIG.
What was shown in was common. 6, the wireless communication system 23 includes a center 24, a communication control device 25, a telephone line 26, a wireless master device 27, wireless slave devices 28a and 28b, a detector 29, a meter 30, and the like. The center 24 is wirelessly connected between a wireless master device 27 and a wireless slave device 28 via a communication control device 25 and a telephone line 26 using a radio wave such as a low-power wireless standard. Wireless base unit 27, wireless slave unit 28
Are driven using a battery or a commercial AC power supply as a power supply. The wireless slave unit 28a is connected to a detector 29 for detecting a gas leak or the like, and transmits an alarm signal to the wireless slave unit 28a. When the wireless slave unit 28a receives the alarm signal, the wireless slave unit 28a transmits an alarm signal to the wireless master unit 27. I do. The wireless master device 27 analyzes the received information and notifies the center 24 via the telephone line 26. The center 24 transmits a command such as gas shutoff to the wireless slave device 28 b connected to the meter 30 via the wireless master device 27.

[0003]

However, in the above-mentioned conventional radio communication system, the radio cell station 27 and the radio cell station 28
There may be various devices that generate noise in the surrounding area. In addition, the wireless master device 27 and the wireless slave device 2
8 in the real environment, around each wireless device, in the wireless section,
Radio wave shields such as metal may be placed. Therefore, the wireless communication system 23 once installed after confirming the communication
However, there has been a problem that communication becomes impossible due to noise and shielding, and an alarm signal from the detector 29 cannot be transmitted to the center 24.

An object of the present invention is to increase the reliability of a wireless communication system by transmitting a warning signal when communication becomes impossible.

[0005]

According to the present invention, in order to solve the above-mentioned problems, a wireless master unit connected to a center periodically sends a test signal to a wireless slave unit. When a response signal of the test signal cannot be received from the wireless slave device within a predetermined time, a warning signal is transmitted to the center, so that communication failure due to noise and shielding can be easily transmitted to the center.

[0006]

According to a first aspect of the present invention, a wireless communication system includes a wireless master unit connected to a center and a wireless slave unit connected to a detector. A wireless communication system in which communication is performed between the center and the detector by performing communication between the wireless base station, wherein the wireless master unit periodically transmits a test signal to the wireless slave unit. Thus, the wireless master device can transmit a warning signal to the center when a response signal of the test signal cannot be received within a predetermined time from the wireless slave device.

A wireless communication system according to a second aspect of the present invention comprises a wireless master unit connected to a center and a wireless slave unit connected to a detector, and performs communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed between the center and the detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, When transmitting the test signal, the device records information of the test signal, and the wireless master device determines that the reception failure rate of the response signal of the test signal from the wireless slave device exceeds a predetermined value. Can be transmitted to the center.

[0008] A wireless communication system according to a third aspect of the present invention comprises a wireless master unit connected to a center and a wireless slave unit connected to a detector, and performs communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed between the center and the detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, The device transmits a warning signal to the center when the response signal of the test signal cannot be received within a predetermined time from the wireless slave device, and the wireless master device changes the frequency channel at a time interval or By transmitting the test signal a plurality of times, it has become possible to realize various data collection of the slave unit information with high reliability.

A wireless communication system according to a fourth aspect includes a wireless master unit connected to a center and a wireless slave unit connected to a detector, and performs communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed between the center and the detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, When transmitting the test signal, the device records information on the test signal, and the wireless master device transmits information on the reception failure rate when the reception failure rate of the test signal from the wireless slave device exceeds a predetermined value. By transmitting to the center, the wireless master device transmits a test signal a plurality of times at a time interval or by changing a frequency channel,
It has become possible to collect various data of the slave unit information with high reliability.

A wireless communication system according to a fifth aspect comprises a wireless master unit connected to a center and a wireless slave unit connected to a detector, and performs communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed between the center and the detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, The device transmits a warning signal to the center when the response signal of the test signal cannot be received within a predetermined time from the wireless slave device, and the test signal or the warning signal from the wireless master device includes test signal information. , The operation management of the slave unit can be realized with high reliability.

[0011] A wireless communication system according to claim 6 comprises a wireless master unit connected to a center and a wireless slave unit connected to a detector, and performs communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed between the center and the detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, When transmitting the test signal, the device records information on the test signal, and the wireless master device transmits information on the reception failure rate when the reception failure rate of the test signal from the wireless slave device exceeds a predetermined value. By transmitting test signal information to a test signal or a warning signal transmitted from the wireless master device to the center and performing the operation management of the slave device with high reliability, it has become possible.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a schematic configuration diagram of a wireless communication system 1 according to an embodiment of the present invention. As shown in FIG. 1, a wireless communication system 1 includes a center 2, a communication control device 3, a telephone line 4, a wireless master device 5, wireless slave devices 6a and 6b,
It comprises a detector 7, a meter 8, and the like.

The center 2 and the radio base unit 5 are connected via the telephone line 4, and the radio base unit 5 and the radio handsets 6a and 6b use radio waves of a low power radio standard or the like. Connected wirelessly. The wireless handset 6a is connected to a detector 7 for detecting gas leakage and the like, and the wireless handset 6b is connected to a meter 8 such as a gas meter. Wireless master device 5, Wireless slave devices 6a, 6
b Both are driven using a battery or a commercial AC power supply. Meter 8 may be an electric meter or a water meter. When the detector 7 detects a gas leak or the like, the alarm signal is transmitted to the wireless slave device 6a, and the wireless slave device 6a transmits an alarm signal to the wireless master device 5 when receiving the alarm signal. The wireless master device 5 analyzes the received information and notifies the center 2 via the telephone line 4. The center 2 transmits a command for shutting down the gas meter or the like to the wireless slave device 6b connected to the meter 8 via the wireless master device 5.

FIG. 2 is a block diagram showing the configuration of the wireless master device 5. The wireless master device 5 includes a network communication control circuit 9, a message information control circuit 10, a modem circuit 11, a power supply circuit 12, a timer control circuit 13, an antenna 14, and the like. Power supply circuit 12
Supplies power to each part. The timer control circuit 13 sends a time signal to the message information control circuit 10 periodically. The antenna 14 is connected to the modulation / demodulation circuit 11, and sends a radio wave received from the wireless handset 6 to the modulation / demodulation circuit 11. Modulation / demodulation circuit 11
Demodulates the received signal. The message information control circuit 10 analyzes the message received from the demodulation circuit 11. The network communication control circuit 9 transmits the analyzed received message to the center 2 via the telephone line 4.

FIG. 3 is a block diagram showing the configuration of the wireless handset 6. The wireless slave device 6 includes a message information control circuit 18, a modulation / demodulation circuit 19, a signal detection circuit 17, a power supply circuit 20, a timer control circuit 21, an antenna 22, and the like. Power supply circuit 20
Supplies power to each part. The timer control circuit 21 sends a time signal to the message information control circuit 18 periodically. The signal detection circuit 17 detects the alarm signal sent from the detector 7 and transmits the alarm signal to the message information control circuit 18. The electronic message information control circuit 18 creates an electronic message for transmitting information such as gas leakage, and the modulation / demodulation circuit 19 modulates the electronic message and sends the modulated electronic message from the antenna 22.

In the present embodiment, the wireless master device 5 is
, A test signal is transmitted periodically. When transmitting the test signal, retry is performed a plurality of times in order to prevent a false report when wireless communication cannot be performed for some accidental reason. In the test signal, transmission time information and test number information for recording the date and time when the test signal was transmitted, the number of times the test signal was transmitted, the number of tests, and the like are placed.

That is, the wireless master device 5 periodically transmits the time signal from the timer control circuit 21 to the electronic mail information control circuit 18.
Send to The electronic message information control circuit 18 creates an electronic message for the test on which the transmission time information and the number of times of the test are placed, and the modulation / demodulation circuit 19 modulates the electronic message and sends it out of the antenna 22 (transmission of a test signal).

On the other hand, in the radio | wireless handset 6, the antenna 14 is connected to the modulation / demodulation circuit 11, receives the test signal from the radio | wireless base station 5, and sends to the modulation / demodulation circuit 11. FIG. Modulation / demodulation circuit 11
Demodulates the received test signal. Message information control circuit 1
0 analyzes the received message from the demodulation circuit 11 and confirms that the message has been received correctly, and then creates a message for responding to the test signal. (Response signal transmission).

In order to determine that the received telegram has been correctly received, the wireless communication device stores all or part of the contents of the transmitted test signal in the telegram information control circuit, and stores the content. Compare the content with the received content. Further, the communication signal includes a code for detecting a communication error.
For example, a parity check code, a CRC code, or the like is used, and the receiving side checks for a communication error with reference to these codes.

The wireless master device 5 has a plurality of test signals, and it is conceivable that the test signals are changed every transmission.
As the test signal to be transmitted, a simple and short test signal is selected when the communication condition is good, and the transmission time is reduced. When the communication condition is not good, a complicated and long test signal is selected for accurate examination. Alternatively, since the apparatus is just installed while the number of tests is small, a complicated and long test signal may be selected for an accurate check, and a simple and short test signal may be selected as the number increases to reduce the transmission time. In that case, information on the content of the transmitted test signal is included in the test signal. Wireless handset 6
Receives the information on the contents of the test signal and determines whether the test signal has been successfully received.

The wireless handset 6 performs carrier sense intermittently when driven by a battery. In the case of AC power drive, a signal is continuously received. When the test signal from the wireless master device 5 is received normally, the wireless slave device 6
The base station 5 records the information (transmission time information, test number information, etc.) of the test signal for recording the communication failure date and time and the number of times in the message information control means 18 and receives the response signal. Then, the counter of the timer control circuit 13 is cleared, and the center 2 is not notified.

If the response signal from the wireless slave device 6 cannot be received for some reason and the time specified by the counter of the timer control circuit 13 has elapsed, the wireless master device 5 sends the telephone line 4 to the center 2. An alarm signal for communication abnormality is transmitted via. Further, when the reception failure rate exceeds a certain rate, the reception failure rate information indicating the degree of failure in the number of test signal transmissions to the center 2 is transmitted. By receiving this information, the center can periodically and remotely know the change in the installation status. In addition, receiving the information on the reception failure rate allows the user to know in more detail, and the communication method between the wireless master device and the slave device may be switched as needed. For example, a frequency channel used for communication is changed.

Next, the operation will be described. FIG. 4 shows a case where a check signal is periodically transmitted between the wireless slave device 6a and the wireless master device 5 to perform a check. This shows the communication procedure.

As shown in FIG. 4, at a predetermined time, for example, once a day, the wireless master device 5 sends the test signal 3 to the wireless slave device 6a.
1 is retried three times every two minutes. Test signal 31
In the box, transmission time information and information on the number of tests are placed. The specified time of the counter of the timer control circuit 13 is three days.

First, on the first day, the wireless master device 5
The test signal is transmitted three times every two minutes. (Sending 32, 3
3, 34). For example, the wireless handset 6a does not transmit a response signal because it cannot receive any three times for some reason. Subsequently, on the second day, the wireless master device 5 sends a test signal to the wireless slave device 6a.
It is transmitted three times every minute (transmission 35, 36, 37). The wireless handset 6a cannot receive the data three times for some reason. On the third day, the wireless master device 5 sends a test signal to the wireless slave device 6a every three minutes.
Is transmitted twice (transmissions 38, 39, 40). Similarly, the wireless handset 6a cannot receive any data for any reason.

When the specified time of the counter of the timer control circuit 13 exceeds three days (41 in FIG. 4), the wireless master unit
A communication abnormality alarm signal is transmitted via the telephone line 4. (Transmission 42). If the wireless master device 5 cannot transmit to the center 2 due to some abnormality, it is also possible to send a meter shutoff command to the wireless slave device 6b connected to the meter 8 to shut off the meter 8.

Next, FIG. 5 shows a communication procedure in the case where the communication between the wireless slave device 6a and the wireless master device 5 is periodically checked and the test signal reception failure rate exceeds a certain rate.

As shown in FIG. 5, similarly to FIG. 4, once a day at a predetermined time, the test signal 31 is retried from the wireless master device 5 to the wireless slave device 6a three times every two minutes. The specified time of the counter of the timer control circuit 13 is three days.

First, on the first day, the wireless master device 5
To transmit a test signal three times every two minutes (transmission 43, 44,
45). For example, the wireless handset 6a transmits a response signal upon normal reception. Upon receiving the response signal, the wireless master device 5 clears the counter of the timer control circuit 13 and records test signal information (transmission time information, test number information, etc.). Subsequently, on the second day, wireless master device 5 transmits a test signal to wireless slave device 6a three times every two minutes (transmissions 46, 47, and 48).

The wireless handset 6a normally receives all three times. The wireless handset 6a transmits a response signal upon normal reception. On the third day, the wireless master device 5 sends a test signal to the wireless slave device 6a every three minutes.
Send twice. (Transmission 49, 50, 51). Wireless handset 6a
The first time and the second time normally receive and transmit a response signal. 3
The first time (transmission 51) cannot be received for some reason.

Here, the reception failure rate of the test signal is 1/9 times = 0.11, which is about 11%. When the reception failure rate exceeds a certain rate (for example, set to 10%), the radio cell station 5
Transmits information on the reception failure rate to the center 2 via the telephone line 4. In this case, since the reception failure rate (11%) exceeds the fixed rate (10%) (52 in FIG. 5), information on the reception failure rate is transmitted to the center 2 (transmission 53).

As described above, according to the present embodiment, the wireless master device 5
To periodically transmit a test signal to the wireless slave device 6a, and to transmit a warning signal to the center 2 when a specified time elapses without being received due to a communication error or a reception failure rate exceeds a certain rate. Thereby, the communication status due to the change of the installation environment is always checked, and the wireless communication is enabled. In addition, in the event of an emergency such as a gas leak, the alarm from the detector 7 is more reliably reported to the center 2, and the safety of gas use is improved.

The frequency at which the test signal is transmitted from the wireless master device 5, the retry frequency, and the specified time of the counter of the timer control circuit 13 are set internally by the wireless master device 5 and the wireless slave device 6, and are set externally. A setting device (not shown), which is a device for this, and a change from the center 2 are possible.

In this embodiment, the retry method is a method of retrying at intervals of time, but there is a method of retrying by changing the frequency channel or a combination of these methods. For example, in the retry method shown in FIG. 4, immediately after the transmission of the test signal 32, the check transmission is performed by changing the frequency channel. Similarly, there is a method of performing check transmission by changing the channel immediately after the test signals 33 and 34 are transmitted. A channel with a good communication state may be checked by the test signal, and the communication with the best communication state may be used for the communication of the gas leak alarm and the gas cutoff.

[0036]

As described above, according to the present invention, by transmitting a test signal, it becomes possible to transmit a warning signal when communication becomes impossible, thereby improving the reliability of a radio communication system.

[Brief description of the drawings]

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

FIG. 2 is a block diagram illustrating a configuration of a wireless master device according to an embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration of a wireless slave device according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a procedure of a periodic communication check between the wireless master device and the wireless slave device according to the embodiment of the present invention (when a check time elapses due to a communication error);

FIG. 5 is a diagram illustrating a procedure of a periodic communication check between the wireless master device and the wireless slave device according to the embodiment of the present invention (when the test signal reception failure rate exceeds a certain rate);

FIG. 6 is a schematic configuration diagram of a conventional wireless communication system.

[Explanation of symbols]

 1,23 wireless communication system 2,24 center 3,25 communication control device 4,26 telephone line 5,27 wireless base unit 6,28 wireless slave unit 7,29 detector 8,30 meter 9 network communication control circuit 10,18 Message information control circuit 11, 19 Modulation / demodulation circuit 12, 20 Power supply circuit 13, 21 Timer control circuit 14, 22 Antenna 17 Signal detection circuit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Masahiro Yamamoto 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. Terms (reference) 5K033 AA06 BA01 BA02 BA11 CB04 DA01 DA03 DA17 DB16 DB20 EA05 EA06 EA07 5K035 AA03 BB01 BB02 CC03 DD01 EE01 EE07 FF02 GG01 5K042 AA08 CA13 DA32 EA01 FA08 FA11 FA15 HA13 JA01 LA11 LA13 LA13 LA13 DD GG01 GG11 LL01 LL05 LL13

Claims (6)

[Claims] 1. A wireless master unit connected to a center and a wireless slave unit connected to a detector. The center and the wireless slave unit perform communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed with a detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, and the wireless master device transmits the test signal from the wireless slave device. If the response signal of the test signal cannot be received within the predetermined time,
A wireless communication system for transmitting a warning signal to the center. 2. A wireless master unit connected to a center and a wireless slave unit connected to a detector, and the center and the wireless slave unit perform communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed with a detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, and the wireless master device transmits the test signal. Then, the information of the test signal is recorded, and the wireless master device,
When the reception failure rate of the response signal of the test signal from the wireless handset exceeds a predetermined value, information on the reception failure rate is transmitted to the center. 3. A wireless master unit connected to a center and a wireless slave unit connected to a detector, and the center and the wireless slave unit perform communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed with a detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, and the wireless master device transmits the test signal from the wireless slave device. If the response signal of the test signal cannot be received within the predetermined time,
A wireless communication system, wherein a warning signal is transmitted to the center, and the wireless master device transmits a test signal a plurality of times at time intervals or by changing frequency channels. 4. A wireless master unit connected to a center and a wireless slave unit connected to a detector, and the center and the wireless slave unit communicate with each other by performing communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed with a detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, and the wireless master device transmits the test signal. Then, the information of the test signal is recorded, and the wireless master device,
If the reception failure rate of the test signal from the wireless handset exceeds a predetermined value, information on the reception failure rate is transmitted to the center, and the wireless master device sets a time interval or a frequency channel. Alternatively, a wireless communication system that transmits a test signal a plurality of times. 5. A wireless master unit connected to a center and a wireless slave unit connected to a detector, and the center and the wireless slave unit perform communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed with a detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, and the wireless master device transmits the test signal from the wireless slave device. If the response signal of the test signal cannot be received within the predetermined time,
A wireless communication system, wherein a warning signal is transmitted to the center, and test signal information is included in a test signal or a warning signal from the wireless master device. 6. A wireless master unit connected to a center and a wireless slave unit connected to a detector, and the center and the wireless slave unit perform communication between the wireless master unit and the wireless slave unit. A wireless communication system in which communication is performed with a detector, wherein the wireless master device periodically transmits a test signal to the wireless slave device, and the wireless master device transmits the test signal. Then, the information of the test signal is recorded, and the wireless master device,
When the reception failure rate of the test signal from the wireless handset exceeds a predetermined value, information on the reception failure rate is transmitted to the center, and the test signal or the warning signal from the wireless base station includes the test A wireless communication system carrying signal information.