JPH08154278A - Transmission reception system for small power radio installation - Google Patents

Abstract

PURPOSE: To allow a system to meet regulations by the Radio Wave Law and to reduce the power consumption by stopping power supply for a 2nd prescribed time every time power is supplied to a transmission means of a transmitter for a 1st prescribed time. CONSTITUTION: A transmission control means 11 of a transmitter 1 outputs a signal of a format in which information of a preamble of a synchronization period length required at minimum for a communication system is set to the head of the signal to a transmitter 7 for plural number of times till a 1st prescribed time elapses when a transmission command is received. On the other hand, a reception control section 28 of a receiver 20 supplies power from the power supply to the receiver 22 for a time corresponding to a length of the format attended with application of power and stops the power supply for a reception stop time based on the 1st and 2nd prescribed times. When the transmission reception system is applied to a gas leakage control system in which a radio wave range is nearly 100m, the regulations of the Radio Wave Law are not violated and the power consumption is reduced much more. Furthermore, the transmitter 1 or the receiver 20 is desirably driven by a battery 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission / reception system for low power radio equipment. In particular, it relates to a transmission / reception system that suppresses power consumption on the transmission device side and the reception device side.

[0002]

2. Description of the Related Art For example, in a general home, a gas meter is outside and a gas leak detector is inside.

In recent years, a system for attaching a low power transmitter to the gas leak detector and a receiver near the gas meter has come to be provided.
In such a gas leak control system, in a general home, the gas meter is outside and the gas leak detector is inside the house, so the distance between the gas meter and the gas leak detector is short. Was set to about 3 m and was not subject to the regulations of the Radio Law (weak radio waves).

And, in such a system,
When the gas leak occurs, the transmitter keeps sending the gas leak message signal (ID of receiving party, bit synchronization, gas leak detection signal, etc.) from the gas leak detector until the gas leak is canceled or the power is stopped. The receiving device supplies power at a constant interval to enter the receiving state, and when it receives the beginning of the gas leak message signal, it continues supplying power and receives the gas leak detection signal, and the gas leak to the gas meter side. I was informed that it had occurred.

[0005]

However, in recent years, the wall tends to have a reinforcing bar structure, and the material of the wall tends to use a material that attenuates radio waves.

Further, a system in which a transmission / reception device is attached instead of the reception device on the gas meter side and the central station (or terminal station) is notified of the occurrence of gas leakage has also been considered.

For this reason, the arrival distance of radio waves is required to be about 3 m to 100 m.

[0008] When the radio equipment with a small electric power reaches a distance of about 100 m, the Radio Law is strictly regulated. According to the Radio Law, the radio equipment with a small electric power emits radio waves for the communication time. Unless the emission of the radio wave is stopped within 3 seconds and 2 seconds have passed, the subsequent transmission is not performed.

However, in the data transmission / reception method used in the conventional gas leakage control system, the reach distance of the radio wave is set to about 3 m and no regulation is imposed. Therefore, the radio wave law for low power radio equipment is regulated. There was a problem that it could not support the method that satisfied the above.

The signal for notifying the gas leak detection (gas leak detection signal) is a kind of abnormal signal and has a very short data length. However, the sender
When a gas leak is detected, the gas leak message signal continues to be transmitted during that period, and the receiving side receives intermittent reception.If the beginning of the gas leak message signal is received during this intermittent reception, reception is continued until the gas leak message signal is stopped. I am continuing.

That is, when a gas leak occurs, despite the fact that the data length of the gas leak detection signal is short,
Since power is supplied to both the transmitting and receiving sides and communication continues,
There was a problem of insufficient power saving.

The present invention has been made to solve the above problems, and provides a transmission / reception system for low-power wireless equipment that satisfies the regulations of the Radio Law for low-power wireless equipment and that can further reduce power consumption. The purpose is to get.

[0013]

A transmission / reception system for low-power radio equipment according to the present invention, when there is an instruction to transmit information, powers the transmission means for a first predetermined time between transmission instructions. A transmitter that supplies power to a transmitting state and stops power supply to the transmitting means for a second predetermined time each time a first predetermined time has elapsed, and a receiver that outputs information received by the receiver to the outside. A transmission / reception system comprising devices,
When a transmission instruction is given, the transmission device outputs a signal of a format in which a preamble having a minimum required synchronization length of the communication system is the head of information to the transmission means a plurality of times until the first predetermined time elapses. The receiving device supplies power from the power supply to the receiver for a time corresponding to the format length when the power is turned on, and supplies power at a reception stop time based on the first and second predetermined times. It is provided with a control unit for stopping.

The information transmission instruction is to transmit the information as abnormal data based on the format when the gas leakage detector detects the gas leakage.

Further, the transmitting device or the receiving device is driven by a battery.

[0016]

According to the present invention, when the transmitting device is instructed to transmit information, the transmitting means is supplied with power for the first predetermined time during the transmission instruction, and the transmitting means is set to the transmission state. Every time the time elapses, the power supply to the transmitting means is stopped for the second predetermined time.

At this time, the control unit of the transmission device outputs the signal of the format in which the preamble of the minimum required synchronization length of the communication system is the head of the information to the transmission means a plurality of times until the first predetermined time elapses. . For this reason, the transmission means is excited by the data of this format, and the transmission data during the first predetermined time has a format in which the preamble of the minimum required synchronization length of the communication system is set as the head of the information, and is repeated a plurality of times. The signal is transmitted, and thereafter, the transmission is stopped for a second predetermined time.

Further, the control unit of the receiving device supplies power from the power source to the receiver for a time corresponding to the format length from the transmitting device when the power is turned on, and based on the first and second predetermined times. The power supply is stopped each time the reception stop time is reached.

When the gas leak detector detects a gas leak, the information is transmitted as abnormal data based on the format.

Further, the transmitting device or the receiving device is driven by a battery.

[0021]

FIG. 1 is a schematic configuration diagram of an embodiment. In the figure, reference numeral 1 is a transmitter provided on the gas leak detector side. The transmission device 1 has at least the following configuration.

The transmitter 1 comprises a reference pulse generating circuit 3, a DC converter for converting an AC voltage into a predetermined DC voltage, and a control unit 9 for controlling the transmitter 7 at a predetermined timing to send a message.

Reference numeral 11 is a transmission control control means. The transmission control means 11 is provided in the control unit 9, and the transmission cycle for sending at least one message is preset, the transmission time is set to 2.56 s, the transmission stop time is set to 2.13 s, and gas leakage is detected. Then, the transmitter 7 is controlled based on this cycle. Both of these times are measured by an internal timer.

This transmission cycle complies with the regulations of the Radio Law, which is prescribed in the radio equipment of a low-power radio station.

Reference numeral 13 is a message sending means. The message sending unit 13 is provided in the control unit 9 and stores the format of the frame with the preamble at the head,
This format is transmitted 12 times in accordance with the transmission instruction. The number of times of transmission is counted by the counter 15, and the counter 15 is reset when counting 12 times.

Further, this format has a 138-bit preamble, a 31-bit frame synchronization (SC),
It has a 63-bit ID and 24-bit detection data (because it is gas leak detection data).

Reference numeral 20 is a receiver on the gas meter side. The receiving device 20 includes at least the receiver 22, the battery 24,
The reference pulse generation circuit 26, the reception control unit 28, the data detection unit 30 and the like are included. This gas meter has a built-in microcomputer.

The reception control unit 28, when the power is turned on,
By the reception start instruction that is output, the battery 24 enters the operating state based on the electric power, and the reference pulse generation circuit 26
Based on the pulse from the receiver 22 for 0.39 s
To 0.36s after the lapse of 0.39s, the power supply is stopped for 6.65s.

That is, the reception cycle is set to 7.04 s. In addition, this reception cycle is based on the preamble length on the transmission side, and is always at least 2 during one preamble.
It is a reception cycle required to receive the 0-bit preamble.

The data detector 30 detects the data received by the receiver 22 based on the pulse from the reference pulse generator 26 and outputs it to the outside.

Next, the operation will be described. FIG. 2 is a timing chart for explaining the operation of the embodiment. In the figure, it is assumed that the gas leak detector and the gas meter with a microcomputer are in the operating state.

For example, when the receiving apparatus 1 takes a reception time of 0.39 s with a reception cycle of 7.04 s in response to a reception start instruction, the gas leak detector detects a gas leak after a lapse of time. Then, the transmitter 1 provided in the gas leak detector operates as follows.

When the gas leak detection signal (transmission instruction) is output, the transmission control means 11 causes the reference pulse generation circuit 3 to operate.
Power transmitter 7 for 2.56 s based on pulses from

Further, this gas leak detection signal (transmission instruction)
The message sending means 13 outputs the 138-bit preamble and the 31-bit frame synchronization (S
C), 63-bit ID, 24-bit gas leak detection data (hereinafter referred to as abnormal data) is output to the transmitter 7,
The counter 15 counts each time this format is output, and when the count value reaches 12, resets and outputs a transmission stop signal. That is, as shown in FIG. 2, 12 frames are transmitted during 2.56s.

That is, in the present system, on the transmitter side, in the case of low power radio equipment, the communication time must be after the radio wave is stopped within 3 seconds after the radio wave is emitted and after 2 seconds have elapsed. For example, in order to comply with the Radio Equipment Regulations of the Radio Law, which is supposed not to perform subsequent transmission, when the number of bits of 12 formats reaches 2.56s by the counter on the transmitting device side. , The power supply is stopped to stop the emission of radio waves, and the stop time is 2.
13s.

Therefore, when transmitting some kind of message, a long stop time is set for a predetermined transmission period, and when transmitting, a plurality of frames in which information is added to the preamble in which unnecessary preambles are removed are created. Since the data is transmitted in the same manner, the transmission power can be reduced and reliable reception is possible.

Then, the message sending means 13 stops the transmission for 2.13s as shown in FIG. 2 in response to the stop instruction.

Further, since the receiving device 20 on the gas meter side supplies power to the receiver 22 for a preset receiving cycle of 7.04 s and for a maximum of 0.39 s, the receiving device 20 from the transmitting side At least one format can be received among the 12 formats having the preamble at the beginning in 2.56 s.

Therefore, since the reception time can be greatly reduced, power consumption on the reception side is suppressed and reception is ensured.

Such a system is very effective, for example, when the transmitting side or the receiving side is driven by a battery.

In the above embodiment, the gas leak control system is taken as an example, but any radio equipment with a small electric power and a radio wave reachable distance of about 100 m may be used.

[0042]

As described above, according to the present invention, when the transmitting side gives a transmission instruction, during the transmission instruction, a frame in which a preamble having the minimum required synchronization length of the communication system is set as the head of information is used. Multiple transmissions during the first predetermined time period
After a lapse of a predetermined period of time, the transmission is performed in a transmission cycle in which transmission is stopped for a second predetermined period of time, and the receiving side supplies power to the receiver for a first predetermined period of time when the power is turned on. The reception side is set to the reception state, and after the first predetermined time has elapsed, the transmission side receives the data in the reception cycle in which the reception is stopped based on the transmission cycle of the transmission side. Since the reception stop time becomes long, both the transmitting and receiving sides
The effect that power consumption can be reduced is obtained.

Further, since the second predetermined time is stopped after the first predetermined time has elapsed, for example, the first predetermined time is set within 3 seconds and the second predetermined time is set at 2 seconds or more. Therefore, it is possible to easily comply with the low power radio equipment regulations of the Radio Law.

Further, when the gas leak detector detects a gas leak, the information sending instruction sends information based on the format of the minimum required preamble length in the communication system when the gas leak detector detects the gas leak. Also in the leak control system, it is possible to reduce the power consumption on both the transmitting side and the receiving side, and it is possible to construct the system which complies with the radio equipment rule of the small power of the wave method.

Further, when the transmitter or the receiver is driven by the battery, the power consumption can be reduced on both the transmitter and the receiver, so that the effect of improving the battery saving can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a first embodiment.

FIG. 2 is a timing chart illustrating the operation of the first embodiment.

[Explanation of symbols]

 1 transmitter 3 reference pulse generator 7 transmitter 11 transmission control means 13 message transmitter 20 receiver 22 receiver 24 battery 26 reference pulse generator 28 reception controller 30 data detector

Claims (3)

[Claims] 1. When there is an information transmission instruction, during the transmission instruction, power is supplied to the transmission means for a first predetermined time to put it in a transmission state, and each time the first predetermined time elapses. A transmitter / receiver for stopping power supply to the transmitter during a second predetermined time, and a receiver for outputting information received by a receiver to the outside, wherein the transmitter is When a transmission instruction is given, a control unit that outputs a signal of a format in which a preamble having a minimum required synchronization length of a communication system is set to the head of the information to the transmission means a plurality of times until the first predetermined time has elapsed The receiving device supplies power from the power supply to the receiver for a time corresponding to the format length when the power is turned on.
And a transmission / reception system for low-power wireless equipment, comprising: a control unit that stops the supply of power during a reception stop time based on a second predetermined time. 2. The small electric power according to claim 1, wherein the information transmission instruction is to transmit the information as abnormal data based on the format when the gas leakage detector detects a gas leakage. Transmission and reception system for wireless equipment. 3. The transmission / reception system for low power wireless equipment according to claim 1, wherein the transmitter or the receiver is driven by a battery.