JPH0732502B2 - Remote monitoring controller - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote monitoring control device for surely performing remote monitoring via a wireless communication network such as a so-called teleterminal system or MCA system.

[0002]

2. Description of the Related Art In remote monitoring via a wireless communication network, communication is possible even when the monitoring target is mounted on a vehicle or moves, or even when the monitoring target is not near a wired communication network. Therefore, it is also suitably used for a gas supply information monitoring system for stably supplying city gas. In a wireless communication network, it is necessary to perform communication according to a predetermined procedure in order to smoothly perform various uses. FIG. 8 shows the procedure of data transmission in the teleterminal system that performs data transmission in packet units. When the master station calls one of the plurality of slave stations, it takes a period of I1 until the master station telemeter device issues a connection request and confirms the connection. At the time of I1, the line connection between the master station telemeter device and the slave station telemeter device is established. Next, the master station telemeter device makes a data request indicated by to the slave station telemeter device and obtains data indicated by. Time from the start of data request to the acquisition of data I
2 is required. Next, the master station telemeter device issues a disconnection request, the teleterminal system issues a disconnection response to the master station telemeter device, issues a disconnection instruction to the slave station telemeter device, and terminates communication. It takes time I3 from when the master station telemeter device issues a disconnection request until there is a disconnection response.

FIG. 9 shows the operation of the teleterminal system in the communication procedure shown in FIG. The operation starts from step a1, and at step a2, it is determined whether or not there is a call request generated from the teleterminal wireless terminal in response to the connection request from the master station telemeter device, and until the call request is received. stand by. Next, in step a3, it is determined whether or not a predetermined identification code (hereinafter also abbreviated as "ID") included in the call request correctly specifies the calling side and the called side. If the ID is incorrect, the process moves from step a4 to step a5, the line connection is rejected, and the operation ends in step a6. If the ID is not incorrect,
The process proceeds from step a4 to step a7, and the incoming call instruction is transmitted to the teleterminal wireless terminal on the slave station side. Next, at step a8, it is determined whether or not there is an incoming call confirmation from the teleterminal wireless terminal in response to the connection confirmation from the slave station telemeter device. If there is no incoming call confirmation, step a9
Then, for example, the time T1 of 30 seconds is set in the timer and the time is waited. When it is determined in step a8 that there is an incoming call confirmation, in step a10 a call response is transmitted to the teleterminal wireless terminal on the master station side.

Next, at step a11, for example, 256
The timer is reset in order to measure the time T2, which is a second, and is started in step a12. Step a13
Then, it is determined whether to receive a data request or data from the master station or the slave station. When data is received, the process proceeds to step a14, and it is determined whether or not the data is an instruction to disconnect the line. When it is determined that the data is not disconnected, the process proceeds to step a15, and it is determined whether or not the data reception is completed. If the reception is not completed, the process proceeds to step a16, and the data packet is transmitted to the other party of the data transmission. When the data reception is completed in step a15 or the data packet transmission is completed in step a16, the process returns to step a11. When it is determined in step a13 that the data is not received, step a1
In step 7, the timer counts and the time is measured, and step a18
Then, it is determined whether or not the time T2, which is 256 seconds, elapses. When it is determined that the time T2 has not elapsed, the process returns to step a13.

When it is determined in step a14 that disconnection data has been received, or when the time T2 has expired in step a18, a disconnection instruction is transmitted in step a19. When the line disconnection is instructed, each teleterminal wireless terminal is stipulated to return a disconnection confirmation to the teleterminal system. In step a20, it is determined whether or not the disconnection is confirmed. When it is determined that there is no disconnection confirmation, in step a21, the timer is set only for T3 time which is, for example, 10 seconds, and the time is waited. Step a20
If it is determined that there is a disconnection confirmation in step a2
The operation ends in 2.

[0006]

When wireless communication is started according to the procedure shown in FIG. 8, it takes, for example, 15 seconds as the time I1 for establishing the line connection and 2-3 seconds as the time I3 for disconnecting the line. It takes a degree. further,
Since waiting for the time T1 or T2 is performed in the teleterminal system, if the line connection is established and disconnected every time data communication is performed, it becomes difficult to transmit data quickly. For this reason, it is also necessary to continue data transmission once the line connection is established. In the tele-terminal system, for example, the above-mentioned T2 which is 256 seconds.
If communication is not continued within the time of, the line connection will be disconnected. In addition, in the MCA system, the line connection is disconnected if communication is not performed for 60 seconds or more. On the other hand, the sampling of the data detected by the slave station device may require a time exceeding this time limit.

An object of the present invention is to provide a remote monitoring control device capable of performing reliable remote monitoring by using a wireless communication network which disconnects a line connection when communication is not performed within a fixed time.

[0008]

According to the present invention, a wireless communication network for disconnecting a line connection between a slave station device and a master station device when the line connection is established and communication is not performed for a predetermined time or more. In the remote monitoring control device, which is connected via the slave station device to remotely monitor the monitoring target via the slave station device, the master station device includes a calling unit that makes a predetermined emergency call, and the slave station device Is a detection unit for detecting an emergency call from the master station device, a timer for measuring a second time period less than the first time period, and the emergency call is detected in response to outputs from the detection unit and the timer. At this time, the monitoring process of detecting the data to be monitored from the monitoring target and transmitting it to the master station device is performed, and the monitoring process is repeated until the predetermined stop command is received from the master station device, and the data transmission interval is the first 2 hours have passed When is a remote monitoring and control device characterized by comprising a control means for controlling to transmit a pseudo data predetermined in the parent station.

Further, in a preferred aspect of the present invention, the control means reestablishes the line connection to the master station device and continues the monitoring process when the line connection is disconnected due to an abnormality in the wireless communication network. It is characterized by controlling.

Further, in a preferred aspect of the present invention, the wireless communication network charges according to a communication amount, the second time is set to be slightly shorter than the first time, and the pseudo data is set to a minimum charge. It is characterized in that it is a unit communication amount.

[0011]

According to the present invention, the slave station device and the master station device are connected via a wireless communication network. The wireless communication network disconnects the line connection when the line connection is established and communication is not performed for a predetermined first time or longer. The master station device includes calling means for making a predetermined emergency call. The slave station device includes a detection unit, a timer, and a control unit. The detection means detects an emergency call from the master station device. The timer measures a second time less than the first time. The control unit responds to the outputs from the detection unit and the timer, and after the emergency call is detected, performs the monitoring process of detecting the data to be monitored from the monitoring target and transmitting the data to the master station device. Further, the monitoring process is repeated until a predetermined stop command is received from the master station device, and when the data transmission interval exceeds the second time, predetermined pseudo data is transmitted to the master station device. When the stop command is received from the master station device, the monitoring process is stopped. Since the slave station device repeats data transmission after the line connection is once established by an emergency call from the master station device, necessary data can be quickly and surely transmitted to the master station device.

According to a preferred embodiment of the present invention,
The control means of the slave station device reestablishes the line connection to the master station device when the line connection is disconnected due to an abnormality of the wireless communication network,
Control is performed so that the monitoring process is continuously performed. As a result, the line connection state for data transmission can be reliably maintained.

According to a preferred embodiment of the present invention,
Although the wireless communication network charges according to the communication amount, the second time is set to be slightly shorter than the first time, and the pseudo data is the communication amount of the minimum charge unit, so that the line connection state is maintained. The cost required for can be minimized.

[0014]

1 is a block diagram of a slave station device 1 according to an embodiment of the present invention.
3 is a block diagram showing a schematic electrical configuration of FIG. In the slave station device 1, the slave station telemeter device 2 receives power from a slave station power supply 3 which is realized by a battery or an alternating current (hereinafter abbreviated as “AC”) power supply device. In the slave station telemeter device 2, an LC realized by a telemeter transmission circuit 4, a power receiving circuit 5, a teleterminal wireless terminal 6 and a liquid crystal display element (hereinafter abbreviated as “LCD”).
The D display 7 and the like are included. Teleterminal wireless terminal 6
Are connected to the transmitting / receiving antenna 8 and the receiving antenna 9.

Pressure transmitters 11 and 12 for generating monitoring data are connected to the slave station telemeter device 2 via sensor connection connectors 13 and 14, respectively. The sensor connection connectors 13 and 14 are connected to the telemeter transmission circuit 4 via barrier terminals 15 and 16 that electrically insulate and transmit only signals.

A booster circuit 17 is included in the power receiving circuit 5. The booster circuit 17 includes a direct current (hereinafter abbreviated as “DC”) 24 required to drive the pressure transmitters 11 and 12.
V is generated. The switch 1 is equivalently provided in the booster circuit 17.
8 is provided so that the output of DC 24V can be controlled intermittently. A constant voltage circuit 19 for generating DC7.2V for the teleterminal wireless terminal 6 and DC5V for operating the telemeter transmission circuit 4 is also provided in the power receiving circuit 5.

In the telemeter transmission circuit 4, a central processing unit (hereinafter abbreviated as "CPU") 20, a timer 21, a random access memory (hereinafter abbreviated as "RAM") 2 are provided.
2. Read-only memory (hereinafter abbreviated as "ROM") 23
And an interface circuit (hereinafter abbreviated as “I / F”) 24 and the like. A processing program for the CPU is preset in the ROM 23. Pressure transmitter 11,12
The output from is given to the CPU 20 via the I / F 24. The CPU 20 is bidirectionally connected to the teleterminal wireless terminal 6 and transmits data and receives commands. LC
The D display 7 displays data processed by the CPU.

FIG. 2 shows a slave station telemeter device 2 shown in FIG.
A configuration of a gas supply information monitoring system will be shown as an example of a telemeter system using the. Portions corresponding to those in the configuration shown in FIG. 1 are designated by the same reference numerals. Child station telemeter device 2
Is provided near the instrumentation equipment 28 of the gas supply pipe 27, for example. The instrumentation equipment 28 detects the secondary pressure of the governor 29 provided in the gas supply pipe 27. Monitoring stations 31 to 35 for detecting such secondary pressure of the governor
Is connected to a master station telemeter device 41 via a teleterminal system 40 including a management device 36 and a timer 37 so that data can be transmitted. Monitoring stations 31-35
Via the tele-terminal system 40, 800MHz
Using radio waves of the band, data transmission is performed with the master station telemeter device 41 in units of a predetermined packet.

The master station telemeter device 41 is 800 MHz.
It has an antenna 42 for transmitting and receiving radio waves of the band,
A teleterminal wireless terminal 43 is connected to the antenna 42. The personal computer 44 processes data and commands transmitted / received by the teleterminal wireless terminal 43. A display device 45 such as a cathode ray tube (abbreviated as “CRT”), an input device 46 such as a keyboard (abbreviated as “KB”), and an output device 47 such as a printer (abbreviated as “PRT”) are connected to the personal computer 44, and a hard disk is connected. A storage device 48 such as (abbreviation “HD”) is also incorporated. The personal computer 44 stores the data received via the tele-terminal wireless terminal 43 in the storage device 48, and in accordance with the instruction from the input device 46, the display device 4
5 is displayed or printed from the output device 47 and output. When it is determined that the monitoring data transmitted from the monitoring stations 31 to 35, which are unmanned slave stations, is abnormal, the display device 45 and the output device 47 give an alarm. The teleterminal wireless terminal 43 is energized by a switching regulator 49. The switching regulator 49 and the personal computer 44 are supplied with electric power from a commercial AC 100V via a constant voltage constant frequency power source (abbreviated as “CVCF”) 50. Even if the AC100V power failure occurs, the constant-voltage constant-frequency power source 50 has a built-in battery, so that power is supplied for a certain period of time.

From the master station telemeter device 41, emergency polling can be performed to each of the monitoring stations 31 to 35 when an alarm is issued. Emergency polling
For example, when construction is performed near the gas supply pipe 27, it is also performed for the monitoring station 31 provided near the construction.

FIG. 3 shows the operation of the master station telemeter device 41 at the time of emergency polling. The operation is started in step b1, and in step b2 the monitoring station 31 which is a slave station.
Wait until receive data from ~ 35. Step b2
When the data from the slave station is received at step b3, it is determined at step b3 whether to perform polling again or disconnect the line connection. When polling is performed, a data request is transmitted in step b4. When polling is not performed, a disconnection signal is transmitted in step b5.

FIG. 4 shows the operation of the slave station device in response to emergency polling from the master station device. When the emergency poll from the master station is received in step c1, it is determined in step c2 whether or not a STOP request, that is, a stop request by a Break signal or the like is received from the master station device. If not received, it is determined in step c3 whether or not one sampling of data from the sensors such as the pressure transmitters 11 and 12 shown in FIG. 1 has been completed. When one sampling has been completed, a subroutine for monitoring the line status and restoring the line at the time of abnormal disconnection is executed in step c4, and sampling data is transmitted to the master station device in step c5. At the next step c6, the timer 2 shown in FIG.
1 is reset, the timekeeping for holding the line is started, and the process returns to step c2.

When it is determined in step c3 that one sampling of the sensor data has not been completed, it is determined in step c7 whether or not the line holding time is about to time out. For example, when it is not ten seconds before the time T2 of 256 seconds in the teleterminal system, the process returns to step c2. When it is determined in step c7 that the time-out is about to occur, step c8
Then, the same line state monitoring and line restoration subroutine as in step c4 is executed. Next, in step c9, a dummy data packet is transmitted from the child station. The dummy data packet is pseudo data that minimizes the charging unit of the teleterminal system. Next, in step c10, the master station device also receives the dummy data packet and transmits it again to the slave station device. In step c11, the slave station device receives the dummy data packet and secures the transmission right. Then, in step c12, the timer for line holding is started in the same manner as in step c6, and the process returns to step c2.

When a STOP request is received from the master station device in step c2, sampling of sensor data is interrupted in step c13. In step c14, the line disconnection from the master station device is received, in step c15, the function of the slave station device is stopped, the response mode to the emergency polling is terminated, and the normal mode is returned to.

FIG. 5 shows a subroutine for monitoring the line status in steps c3 and c8 of FIG. 4 and repairing the line when an abnormal disconnection occurs. The operation is started in step d1, and it is determined in step d2 whether the line connection is held. When the line connection is not held, a connection request is transmitted to the master station device in step d3. Step d
At 4, it is determined whether or not a disconnection instruction is received from the master station device. When the disconnection instruction is received, the process returns to step d3. When the disconnection instruction is not received, the process moves to step d5, and it is determined whether or not the connection confirmation is received from the master station. When the connection confirmation is not received from the master station, the process returns to step d4. When it is determined that the line is held in step d2 and when the connection confirmation is received from the master station in step d5, the process ends in step d6.

FIG. 6 shows the structure of data transmitted in the teleterminal system shown in FIG. In the teleterminal system, each transmitted data is handled in each form of packets 51-57.

FIG. 7 shows the packets 51 to 57 shown in FIG.
2 shows a schematic configuration of a signal S transmitted as. One packet is roughly divided into three parts, a header, data, and a footer. The header includes, for example, a start signal S1, a self-identification signal S2, a partner identification signal S3, and the like. The data is secured so as to have a data amount preset as the transmission data S4. When the amount of data to be transmitted is larger than the predetermined amount of data, the data is transmitted by a plurality of packets. Therefore, a signal indicating whether data continues or the data ends is added to each data signal S4. In the present embodiment, "ETB" indicating the continuation of the text is added to the data signal S4 when transmitting the data in step c5. As a result, the slave station device holds the transmission right. This is because the transmission right is transferred to the master station device when "ETX" indicating the end of the text is added. The footer includes the end signal S5. A predetermined failure code is added to the end signal S5 when a communication failure occurs in the teleterminal system. The teleterminal system can perform data transmission in such packet units at a high speed, and can realize many lines in a time division manner.

In the above embodiment, although the tele-terminal system is used as the wireless communication network, MC
Of course, the A system or the like may be used.

[0029]

As described above, according to the present invention, when the slave station device detects an emergency call from the master station device, only data transmission is continuously performed with the transmission right held after the line connection is established. Therefore, the monitoring target can be reliably monitored remotely by the master station device via the slave station device.

Further, since the line connection can be reestablished from the slave station device when the line connection is disconnected due to an abnormality in the wireless communication network or the like, more reliable remote monitoring can be performed.

Even when the wireless communication network charges for the amount of communication, the second time is set to be slightly shorter than the first time, and the pseudo data is the communication amount of the minimum charge unit. , Can reduce the cost of maintaining line connection.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic electrical configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a gas supply information monitoring system using the slave station telemeter device shown in FIG.

FIG. 3 is a flowchart showing an operation of the master station telemeter device shown in FIG.

FIG. 4 is a flowchart showing an operation of the slave station telemetry device shown in FIG.

5 is a flowchart showing the operation of the slave station telemeter device shown in FIG.

FIG. 6 is a diagram showing a data structure in the teleterminal system shown in FIG. 2;

FIG. 7 is a diagram showing a packet configuration in the teleterminal system shown in FIG. 2;

FIG. 8 is a diagram showing a data transmission procedure in the teleterminal system.

FIG. 9 is a flowchart showing the operation of the teleterminal system.

[Explanation of symbols]

 1 Slave station device 2 Slave station telemeter device 4 Telemeter transmission circuit 6,43 Teleterminal wireless terminal 8,42 Antenna 11,12 Pressure transmitter 20 CPU 21,37 Timer 22 RAM 23 ROM 27 Gas supply pipe 28 Instrumentation equipment 29 Governor 31-35 Monitoring Station 36 Management Device 40 Tele Terminal System 41 Master Station Telemeter Device 44 Personal Computer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H04Q 7/38

Claims (3)

[Claims] 1. A slave station apparatus and a master station apparatus are connected via a wireless communication network that disconnects the circuit connection when communication is not performed for a predetermined time or more even if the circuit connection is established, and the master station is connected. In a remote monitoring control device for remote monitoring of a monitoring target by a device via a slave station device, the master station device includes calling means for making a predetermined emergency call, and the slave station device is an emergency from the master station device. When the emergency call is detected in response to the output from the detection unit and the timer, the detection unit that detects the call, the timer that measures the second time less than the first time, and the timer that should be monitored A monitoring process of detecting data and transmitting the data to the master station device is performed, and the monitoring process is repeated until a predetermined stop command is received from the master station device, and when the data transmission interval exceeds the second time, Predetermined doubt Remote monitoring and control device characterized by comprising a control means for controlling to transmit the data to the master station. 2. The control means, when the line connection is disconnected due to an abnormality in the wireless communication network or the like, re-establishes the line connection to the master station device and controls so as to continue the monitoring process. The remote monitoring and control device according to claim 1. 3. The wireless communication network charges according to a communication amount, the second time is set to be slightly shorter than the first time, and the pseudo data is a communication amount of a minimum charge unit. The remote monitoring and control device according to claim 1 or 2.