JP2634712B2 - Communication method using digital wireless network - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication method for reliably transmitting data from a local station to a partner station using a digital radio network called a so-called teleterminal system.

[0002]

2. Description of the Related Art For example, if an abnormality occurs in the middle of a piping system of city gas or the like, there is a risk of dangerous disaster such as fire or explosion. In order to prevent such disasters, the secondary pressure of the governor installed in the piping system is detected, and if an abnormality occurs, it is immediately reported to the management center to prevent the disaster. is important. Conventionally, a signal indicating the result of detection from a governor or the like is transmitted to a management center or the like using a public telephone line or a dedicated wired line.

[0003]

The conventional method of transmitting monitoring data using a public telephone line or a dedicated wired line requires a communication line to be connected by a wire.
It cannot be easily done quickly when a connection to the line is required. Further, when the degree of disaster becomes severe, the wired line is disconnected due to the disaster, and there is a possibility that a signal cannot be transmitted.

[0004] Conventionally, monitoring information such as governor has also been transmitted wirelessly. In the case of wireless transmission, the size of an antenna or the like may be small especially in a short wavelength range, so that a communication device can be provided immediately when necessary. However, radio waves are widely used, and it is necessary to use only a pre-allocated frequency band in order to prevent other users from being interfered or interfered with, It is very difficult to get a new frequency band assigned when the need arises. Therefore, it is conceivable to perform communication using a digital wireless network to which a frequency of a radio wave has already been assigned. Even if a digital wireless network is used, a communication failure due to radio wave interference in space or the like is inevitable as long as it is wireless, and various failures may occur in the digital wireless network itself.

[0005] An object of the present invention is to provide a communication method capable of reliably performing communication using a digital wireless network.

[0006]

According to the present invention, when a failure occurs in communication from the own station to the other station, the digital radio network gives a signal indicating the type of the failure to the own station, and the own station receives the signal. A communication method using a digital wireless network, wherein a type of a failure is detected by a signal, and a procedure for reconnection to a partner station is repeatedly performed at predetermined time intervals for each type of the detected failure. .

Further, according to the present invention, the own station includes a timer, and in a predetermined communication sequence, a communication failure indicates a line connection,
The type of fault is detected by judging whether the procedure has occurred during data transmission / reception or the line disconnection, and the time set in advance for each procedure is set in the timer. The procedure for reconnection to the partner station is repeatedly performed.

Further, the present invention is characterized in that, when the own station detects that a communication failure has occurred in the procedure of line disconnection in a predetermined communication sequence, the own station stops the procedure of reconnection to the partner station. I do.

[0009]

According to the present invention, the own station detects the type of a failure by a signal given from a digital radio network, and executes a procedure for reconnection to a partner station at a predetermined time interval for each type of the failure. Repeat. As a result, the possibility of reconnection is increased, and communication can be reliably performed.

Further, according to the present invention, the own station determines the type of the failure by determining whether a communication failure has occurred in a predetermined communication sequence in any of line connection, data transmission / reception, and line disconnection. Is detected. A predetermined time is set in the timer for each procedure, and the procedure for reconnecting to the partner station is repeated while waiting for the time set in the timer, so that the possibility of communication at the time of reconnection is reduced. Can be enhanced.

Further, according to the present invention, when the own station detects that a communication failure has occurred during the line disconnection procedure in a predetermined communication sequence, it cancels the procedure for reconnection to the partner station. Since the data transmission / reception procedure has been completed in the predetermined communication sequence, the consumption of the battery can be prevented by not performing the reconnection procedure.

[0012]

FIG. 1 is a block diagram showing an electrical configuration for carrying out the present invention. The partner station 1 is communicably connected to the own station 2 via the digital wireless network 3. The partner station 1 has a processing unit (DTE) 11, a communication adapter (TE) 12,
An antenna 13, a display unit 14, an output unit 15, and the like are provided. The partner station 1 is provided in a security management room or the like,
Power is supplied from a commercial AC power supply (AC 100 V) 16. The processing unit 11 includes a communication adapter 12 and an antenna 13
, And performs bidirectional communication with the digital wireless network 3 using 800 MHz band radio waves.

The own station 2 includes a processing unit (DTE) 21, a communication adapter (TE) 22, and an antenna 23, and
Two-way communication is performed with the digital wireless network 3 using radio waves in the MHz band. The own station 2 is arranged, for example, near a governor 24 provided in the middle of a gas supply path. Governor 24
Is adjusted by the valve opening so that the gas pressure does not fluctuate even if the gas supply amount to the consumer changes. The sensor 25 detects the opening degree of the valve and sends a signal to the processing unit 21.

The processing unit 21 includes a central processing unit (hereinafter referred to as “C
PU "), memory 28 and waiting time T
User timers 31 and 3 for setting 1, T2 and T3
2,33 are included. The CPU 27 operates according to a program set in the memory 28 in advance. Sensor 2
When it is detected from the output from 5 that the opening of the governor 24 has become abnormal, a call is made to notify the partner station 1 of the abnormality.

The processing unit 21 and the communication adapter 22 are connected to an AC power supply (AC 100 V) and are energized by a power supply 26 including a backed-up battery. Power supply 2
6 supplies the power from the AC power supply to the processing unit 21 and the communication adapter 22 and charges the battery when the AC power supply is normal. When the AC power supply fails, the power charged in the battery is supplied to the processing unit 21 and the communication adapter 22.

The digital radio network 3 receives a radio signal from the partner station 1 or the own station 2 and transmits the signal to the partner by radio. The digital wireless network 3 gives a predetermined reason code to the partner station 1 or the own station 2 when various failures occur. The digital wireless network 3 stabilizes communication failures,
Waiting time T4, T5, T
6, timers 34, 35, 36, and 37 that determine T7 are provided inside.

FIG. 2 shows a configuration of a signal S when communication is performed between the partner station 1 and the own station 2 via the digital wireless network 3. The start signal S1 is given by a predetermined code.
In addition to indicating the start of the signal S, the type of the signal is also indicated. The self-identification signal S2 indicates an identification code predetermined for the partner station 1 or the own station 2 that has transmitted the signal S. Opponent identification signal S
Reference numeral 3 denotes an identification code for the other party. The code or data S4 indicates a predetermined code or data to be sent to the other party, corresponding to the start signal S1. The end signal S5 indicates the end of the signal S.

FIG. 3 is a flowchart showing the operation of the own station 2 according to one embodiment of the present invention. From step a1 to step a2, an abnormality occurs in the own station that should communicate with the other station. In step a3, a signal requesting connection to the partner station 1 is transmitted to the digital wireless network 3. In step a4, it is determined whether or not a connection confirmation signal from the digital wireless network 3 has been received. When the connection confirmation signal is received, a session, which is a connection of a communication line from the own station 2 to the partner station 1, is established in step a5. these,
The procedure from step a3 to step a5 is a line connection procedure.

In step a6, data corresponding to the abnormality that has occurred is transmitted to the partner station 1. In step a7, it is determined whether or not data from the partner station 1 has been received via the digital wireless network 3. This data is various commands from the partner station 1 to the own station with respect to the data from the own station 2. For example, when an abnormality occurs in the governor 24, a possible action to resolve the abnormality is instructed. Steps a6 and a7 are procedures for data transmission and reception.

In step a8, a disconnection request is transmitted to the digital wireless network 3. In step a9, it is determined whether or not a disconnection response signal has been received from the digital wireless network 3. When a disconnection response signal is received, step a
At 10, the session between the own station 2 and the partner station 1 is released. Step a8, step a9, and step a10 are procedures for disconnecting the line.

In step a4, from the digital wireless network 3,
When the connection confirmation signal is not received, in step a11, it is determined whether or not a failure notification has been received from the digital wireless network 3 which is the communication network. When there is no failure notification, the process returns to step a4. When there is a failure notification, step a
In step 12, after waiting for a predetermined T1 time, step a3
And repeat the reconnection procedure. The time of T1 is, for example, 180 seconds.

At step a7, if there is no data reception, at step a13, the digital wireless network 3
It is determined whether or not there is a failure notification. When there is no failure notification, the process returns to step a7. If there is a failure notification, wait for T2 time in step a14,
Return to Step 3 and perform the reconnection procedure. The T2 time is, for example, 300 seconds.

If the disconnection response is not received at step a9, at step a15, the digital wireless network 3
It is determined whether or not there has been a failure notification. If there is no failure notification, the process returns to step a9. If there is a failure notification, the process waits for the time T3 in step a16, and repeats the reconnection procedure in step a3. The time of T3 is, for example, 180
Seconds.

FIG. 4 is a flowchart showing the operation of the digital wireless network 3 when the own station 2 performs the operation shown in FIG. From step r1 to step r2, a call request signal, which is a connection request signal from the own station 2, is received. When the call request is received, a call instruction signal is transmitted to the partner station 1 in step r3. Next, at step r4, it is determined whether or not a call confirmation signal from the partner station 1 has been received. When the call confirmation signal is received, a call response signal is transmitted to the own station 2 in step r5. The procedure from step r2 to step r5 corresponds to line connection.

Next, at step r6, it is determined whether or not data from the own station 2 has been received. When the data is received, the data is transmitted to the partner station 1 in step r7.
Next, in step r8, it is determined whether or not data from the partner station 1 has been received. When the data is received, the data is transmitted to the own station 2 in step r9. Step r10
Then, it is determined whether or not the end of data has been received. The end of the data is determined based on whether or not the data S4 of the signal S shown in FIG. 2 includes a predetermined end code.
If the data continues, the process returns to step r8. The procedure from step r6 to step r10 corresponds to data transmission and reception.

Next, in step r11, it is determined whether or not a disconnection request signal has been received from the own station 2. When the disconnection request signal is received, a disconnection instruction signal is transmitted to the partner station 1 and a disconnection response signal is transmitted to the own station 2 in step r12. These steps r11 and r1
Step 2 corresponds to line disconnection.

If no call confirmation signal is received in step r4, the process waits for a predetermined T4 time in step r13. If the time T4 has not elapsed, the process returns to step r3. If there is no data reception at step r6, at step r14, the process waits for time T5, and if not, the process returns to step r6. If no data has been received in step r8, the process waits for the time T6 in step r15, and if not, the process returns to step r8. If the disconnection request signal is not received in step r11, the process waits for time T7 in step r16, and if not, the process returns to step r11. When the cutting process in step r12 ends, the process ends in step r17.

FIG. 5 shows the operation when the digital wireless network 3 detects an abnormality. In steps r13, r14, r15, and r16 of FIG. 4, when the times T4, T5, T6, and T7 have elapsed, or when any other communication failure has been detected, the digital wireless network proceeds from step c1 to step c2. At
A predetermined reason code corresponding to the detected communication failure is transmitted to the partner station 1 and the own station 2 to notify the failure. Next, in step c3, the lines to the partner station 1 and the own station 2 are disconnected, and the process ends in step c4.

The waiting times T4 to T7 correspond to the digital radio network 3
Is set in advance as an installation rule. For example, T4
Is 180 seconds, T5 is 300 seconds, T6 is 300 seconds, and T7 is 180 seconds. Since communication via the digital wireless network 3 uses wireless communication, the communication can be performed while moving in a vehicle or the like. However, if it is performed while moving, communication often becomes impossible due to temporary radio interference in a building, behind a shadow, or in a tunnel. Each waiting time T4 to T7 is set to a relatively long time so that an established session can be maintained even if such a temporary communication failure occurs.

In the operation of the own station 2 shown in FIG. 3, the waiting time T1 corresponds to the waiting time T4 of the digital wireless network 3 shown in FIG. The waiting time T2 of the own station 2 corresponds to the digital wireless network 3
Correspond to the waiting times T5 and T6. The waiting time T3 of the own station 2 corresponds to the waiting time T7 of the digital wireless network 3.
Generally, since the partner station 1 communicates with a plurality of partners via the digital wireless network 3, a communication failure is likely to occur when the partner station 1 is already communicating. In particular, the other station 1 is already in communication and the so-called slow pole has already caused T4-T
This is likely to occur when waiting for 7 hours. Therefore, even if the own station 2 immediately requests reconnection to the partner station 1, there is little possibility of reconnection. When the own station 2 is driven by a battery, power is consumed every time a signal is generated. For this reason, when the possibility of reconnection is low, it is desirable not to perform the reconnection operation and to reconnect after the possibility increases. User timer 31 shown in FIG.
Is set to the waiting time T of the digital wireless network 3.
4 and the set time T2 of the user timer 32 is made equal to the waiting time T5.
By making 3 equal to the waiting time T7, the possibility of reconnection can be increased.

FIG. 6 shows a communication procedure from the own station 2 to the partner station 1. Is data representing the result of detecting an abnormality to be transmitted from the own station to the partner station. This data is displayed on a display screen provided on the display unit 14 shown in FIG. 1, or is displayed acoustically by a buzzer or the like. In addition, the image is printed out from the output unit 15 on recording paper or the like. Includes the command from the partner station 1 to the own station 2.

FIG. 7 shows a local station 2 according to another embodiment of the present invention.
The operation of FIG. This embodiment is similar to the embodiment shown in FIG.
Corresponding steps have the same reference characters. It should be noted that the session is immediately released in step a10 when a failure notification is made from the communication network in step a15. Even if the line disconnection is not performed normally, data transmission and reception are performed normally, so that the purpose of communication has been achieved and unnecessary consumption of the battery can be prevented. As shown in FIGS. 4 and 5, the digital communication network 3 issues a failure notification and disconnects the line when the waiting of the T7 time ends, so that the process of disconnecting the line from the own station 2 does not have to be performed. .

In each of the above embodiments, the own station 2 detects an abnormality in the opening degree of the governor 24. However, it is needless to say that an abnormality in the pressure on the secondary side, gas leakage, etc. may be detected. It is. In addition, it goes without saying that an abnormality in a factory plant or the like may be detected. In addition, although the partner station 1 communicates with the digital wireless network 3 by radio, it is needless to say that communication may be performed by wire.

[0034]

According to the present invention, the own station repeats the procedure of reconnection to the master unit at predetermined time intervals according to the type of fault given from the digital wireless network, so that communication by reconnection is established. It is highly possible that the communication can be performed reliably, and the consumption of the battery and the like can be prevented.

According to the present invention, the own station includes a timer, sets a predetermined time corresponding to a procedure in which a communication failure has occurred in a predetermined communication sequence in the timer, and sets the predetermined time only for the time set in the timer. Since the procedure for reconnection to the partner station is repeated in a waiting period, the possibility of reconnection is high, communication can be performed reliably, and consumption of a battery or the like can be prevented.

Further, according to the present invention, if the own station detects that a communication failure has occurred in the procedure for disconnecting the line, the own station stops the procedure for reconnection to the partner station. Since data transmission to the partner station has been completed, consumption of an extra battery or the like can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an electrical configuration for implementing the present invention.

FIG. 2 is a diagram showing a configuration of a signal S used in the present invention.

FIG. 3 is a flowchart showing an operation of the own station 2 according to one embodiment of the present invention.

4 is a digital wireless network 3 corresponding to the embodiment shown in FIG.
6 is a flowchart showing the operation of the first embodiment.

FIG. 5 is a flowchart illustrating an operation when the digital wireless network 3 detects an abnormality.

FIG. 6 is a diagram showing a procedure when communication is normally performed in the embodiment shown in FIG. 3;

FIG. 7 is a flowchart showing an operation of the own station 2 according to another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 partner station 2 own station 3 digital wireless network 11, 21 processing unit (DTE) 12, 22 communication adapter (TE) 13, 23 antenna 24 governor 25 sensor 26 power supply 27 CPU 31-33 user timer 34-37 timer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ichiro Sugimoto 4-1-2, Hirano-cho, Chuo-ku, Osaka City Inside Osaka Gas Co., Ltd. (72) Inventor Mitsutoshi Yamada 4-chome Tsunashima Higashi, Kohoku-ku, Yokohama, Kanagawa Prefecture No. 3 Matsushita Communication Industrial Co., Ltd. (72) Inventor Jun Kanda 4-1-1 Tsunashima Higashi, Kohoku-ku, Yokohama City, Kanagawa Prefecture Matsushita Communication Industry Co., Ltd. (56) References JP-A-61-290834 (JP) , A)

Claims (3)

(57) [Claims] When a failure occurs in communication from a local station to a partner station, a digital radio network gives a signal representing the type of the failure to the local station, and the local station detects the type of the failure based on the given signal. A communication method using a digital wireless network, wherein a procedure for reconnection to a partner station is repeatedly performed at predetermined time intervals for each type of detected failure. 2. A self-station includes a timer, and determines a type of a fault by determining whether a communication fault has occurred in a predetermined communication sequence in a line connection, data transmission / reception, or line disconnection procedure. 2. The method according to claim 1, wherein the timer is detected and a predetermined time is set for each procedure in a timer, and the procedure for reconnecting to the partner station is repeated while waiting for the time set in the timer. A communication method using a digital wireless network. 3. The self-station, when detecting that a communication failure has occurred during a line disconnection procedure in a predetermined communication sequence, cancels a procedure of re-connection to a partner station. A communication method using the digital wireless network according to any one of claims 1 to 2.