JP2000019262A - Method and system for observing amount of rain of synchronous type self-activation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and system for observing the amount of rain for enhancing measurement accuracy by preventing data from lacking by a synchronous type self-activation system. SOLUTION: The measurement data and ID signal of a rain gauge are stored in a memory 2, a transmission time generation part 6 generates a transmission control signal when a preset transmission time coincides with time from internal time 5, enables a transmitter 3 to be able to transmit signals, and transmits data being stored in the memory 2. Since the transmission time is determined by time-division so that it does not overlap for a plurality of observation devices, a plurality of observation devices do not transmit signals simultaneously. Although each observation device has an internal clock inside, it corrects time at every fixed time according to a signal from a GPS receiver 7 to prevent time deviation due to the frequency fluctuation of a clock oscillator 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A synchronous self-starting observation device according to the present invention measures rainfall in a rainfall measurement system or the like, and sends the observation result to a data collection processing device at regular intervals for computer processing. The present invention relates to a method and system for rainfall observation for obtaining prediction and warning information on natural disasters from the obtained results.

[0002]

2. Description of the Related Art As a prior art observation apparatus of this kind, an observation apparatus of an asynchronous self-starting system is used, and therefore, transmission times of data of a plurality of rainfall observation apparatuses are not determined irregularly.

[0003] In other words, since transmission starts when rainfall is observed, transmission radio waves are randomly output from each observation device, and reception may not be possible if radio waves overlap.

However, until now, even if there is such a problem, there is little overlap in the transmission time, and even if the accumulated data is transmitted, the accumulated rainfall can be measured even if it is lost. Has been transformed. But,
In the future, the introduction of a synchronous self-starting observation device is indispensable in order to improve the accuracy of measurement and improve the quality of forecasts and warnings of landslide disaster systems.

Further, as a prior art, Japanese Patent Publication No. 58-154
No. 095. This example describes an observation data collection time synchronization method in which observation data at the same time can be easily collected for the purpose. That is, the monitoring station issues an observation data read command to all the observation stations all at once, collects the observation data and stores the observation data in the memory, then sequentially calls all the observation stations, and collects the observation data stored in the memory. It is characterized by.

This embodiment is different from the first embodiment in that one monitoring station and N observation stations are connected by a transmission line, whereas the present invention is wireless.

[0007] The above-mentioned prior known technologies include the following.

Japanese Patent Application Laid-Open No. Hei 9-113655, Japanese Patent Publication No. 2-30077, and Japanese Patent Publication No. 5-65801.

[0009]

Most of the self-starting observation devices used in the prior art output one pulse signal from the rain gauge when the rain gauge measured by the rain gauge measures 1 mm, and at the same time, The transmitter is driven to transmit data.

An asynchronous self-starting observation device that outputs a pulse signal at every 1 mm and simultaneously transmits data is used. As described above, since transmission is performed irregularly in this method, radio waves are duplicated, and in such a case, there is a problem that data cannot be received and data is lost.

It is an object of the present invention to propose a method and system for rainfall observation that prevents data loss and improves measurement accuracy by a synchronous self-starting method.

[0012]

SUMMARY OF THE INVENTION A synchronous self-starting rainfall observation system according to the present invention includes a rain gauge for measuring rainfall, a transmitter for transmitting a pulse signal from the rain gauge to a receiving station, and a rainfall meter. A memory for inputting total data, a clock oscillator for generating a clock signal for generating an ID signal and a transmission time signal, and receiving the clock signal.
An internal clock that generates a parallel time signal of minutes and seconds, and an I that inputs a one-second signal from the internal clock to generate a binary time signal
An AND circuit that performs an AND operation on the D counter, the status output signal of the memory, and the transmission control signal from the transmission time generation unit, and outputs an AND signal when both signals are present; And a transmission time generation unit that outputs a transmission control signal to the transmitter when the times match, and a GPS receiver that corrects the internal clock every predetermined time.

In one embodiment, the apparatus further comprises means for setting a guard time before and after the transmission time of each observation device in order to eliminate the influence of a time shift occurring during the timing correction by the GPS signal. It is.

A method for rainfall observation of the synchronous self-starting type according to the present invention is a rainfall observation method for transmitting a pulse signal from a rainfall gauge to a monitoring station, wherein the rainfall gauge outputs observation data; And a step of storing an ID signal that is timing data indicating the time of data generation and data generation, a step of determining whether transmission data exists in the memory, and a step of determining whether a transmission control signal is output from the transmission time generation unit. Discriminating, transmitting data to the memory from the transmitter when there is transmission data in the memory and a transmission control signal is being output, and stopping the transmission state when the transmission of the stored data is completed. And

[0015] The transmitting step of each of the observation devices may include:
A preferred method of the present invention is that a transmission time is assigned in advance so that each observation station transmits in order, and time is synchronized between the observation apparatuses so that transmission waves from the observation apparatuses can be transmitted stably without overlapping. It is an embodiment of.

Further, the step of outputting a transmission control signal from the transmission time generation section is performed when the time preset in the transmission time generation section and the time output by the internal clock coincide with each other. included.

In one embodiment, the transmission control signal is sent to an AND circuit and also sent to an ID counter to reset the ID counter to 0, and the ID counter starts counting from 0 again. .

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present observation apparatus is a rainfall observation apparatus installed in a plurality of areas, performs rainfall observation in each area, and transmits the measured data by radio (radio wave).
To the receiving station where the data collection processing device is located. When wireless transmission to a receiving station is performed using the same transmission frequency for all observation stations, if the plurality of observation stations transmit simultaneously, it becomes difficult for the receiving station to receive normally.

For this reason, by synchronizing the time between the observation stations and allocating the transmission time in advance so that the observation stations sequentially transmit, a plurality of observation stations are prevented from transmitting at the same time. .

Further, the rainfall data until the time when the next transmission starts is stored in the observation device, and the observation device transmits the stored data at the time of transmission.

The features of the observation device of the present invention will be described with reference to FIG. A rain gauge 1 is connected to the observation device placed outdoors, and the rain gauge 1 measures rainfall and sends the measurement data to the observation device.

Then, the data is recorded in the memory 2 in the observation device. At the same time, the ID signal from the internal clock 5 is also recorded in the memory 2.

When the amount of rain is measured when the rain starts to fall and the data is recorded in the memory 2, the ID signal is also recorded in the memory 2 at the same time. The ID signal is
This is a time signal required to know the change in rainfall.

The internal clock 5 outputs an ID signal and, at the same time, outputs a parallel time signal of hours, minutes, and seconds, and sends it to the transmission time generator 6. On the other hand, the output of the clock oscillator 4 generates a time signal via the internal clock 5,
Since the transmission time is set in advance in the transmission time generation unit 6, when the set time matches the time from the internal clock 5, a transmission control signal is generated, and the transmitter 3 is set to the transmission state.
The data stored in the memory 2 is transmitted. The transmission time is determined in a time-sharing manner so as not to overlap a plurality of observation devices. By doing so, the transmission from the observation device can be transmitted at a predetermined time, so that a plurality of observation devices do not transmit at the same time.

Further, data not transmitted is stored in the memory 2, so that data is not lost. However, when the rainfall measured by the rain gauge 1 is zero and the rainfall measurement data is not sent, transmission is not performed even at the set transmission time. Each observation device has a clock inside, but a time lag occurs due to a frequency fluctuation of the clock oscillator 4 which is the original clock of the clock, and the time lag becomes a transmission time lag.
The time is forcibly corrected at regular intervals by a signal from a GPS (Global Positioning Satellite) receiver 7.

The internal clock 5 until the next time correction is performed.
A guard time (see FIG. 3) is provided between transmission times predetermined for each observation station so that transmissions do not overlap even if there is a time lag. Therefore, G
In an area where a PS signal can be received, a plurality of observation stations can always transmit at the correct time without overlapping.

Next, the observation method of the self-starting method will be described.

As the observation method conventionally used, two methods, a polling method and a self-starting method, are used.

The outline is as follows.

The polling method is a method in which a receiver for receiving a polling signal is prepared for each observation station, a command is individually sent from the reception station to each observation station, and data is accessed according to the command. . In this system, the transmission radio waves of the observation stations do not overlap, but a receiving device for receiving a command is required for each observation device.

The self-starting method is a method of automatically starting transmission of measurement data when the rainfall of a rain gauge reaches a certain level.

However, since the transmission is started when the rainfall is observed, the transmission radio waves are output from each observation device at random, and the radio waves are duplicated. In this case, the reception may not be possible. Therefore, in the past, when a system using both the polling method and the self-starting method was used in combination, transmission of the self-starting method might be performed during polling, and transmission radio waves might overlap. There was a problem with using the two methods together. However, even when the synchronous self-starting method is used in combination with the polling method, the transmission time of the synchronous self-starting method is clear, so that polling can be performed while avoiding the time. The two methods of the starting method can be used together.

FIG. 2 shows an embodiment in which the observation apparatus of the present invention is used.

At the same time, description will be made also with reference to FIG. In FIG.
It is assumed that there are 10 rainfall observation stations.

Then, there is a receiving station 34 for receiving the transmission radio waves from the observation stations. Here, the receiving stations 34 receive the telemetry radio waves transmitted from the respective observation stations, and collect and process the measured rainfall information.

Then, a synchronization signal for synchronizing the timing of each observation station is taken in from the artificial satellite GPS35. The transmission frequencies transmitted from the observation stations are all the same, and transmission is automatically stopped when data transmission is completed.

The time preset in the observation station 21 now,
Assuming that the time from the internal clock 5 in the observation device matches, the observation station 21 transmits the rainfall data and the ID signal stored in the memory so far.

When the data of the observation station 21 has been transmitted, the transmission of the observation station 22 is started in a manner similar to that of the observation station 21 after a certain guard time. However, if no rainfall is observed at the observation station, no data will be transmitted. In this manner, observation stations # 1 to # 10 sequentially transmit. Each observation device has a built-in GPS receiver 7 as shown in FIG. 1, and the time of the internal clock 5 is periodically corrected by a synchronization signal from the GPS receiver 7.

In the present invention, in particular, in order to minimize the power consumption by the GPS receiver, the G
When the power of the PS receiver 7 is turned on and the time adjustment of the internal clock 5 is completed, the power of the GPS receiver 7 is automatically turned off.

Until the next time correction, a time lag of the internal clock 5 of the observation device can be tolerated.
A guard time is provided at the transmission time determined for each observation station. Therefore, even if the clock frequency fluctuates due to the ambient temperature or other conditions and the transmission time is shifted, transmission from a plurality of observation stations does not overlap.

FIG. 3 shows a time chart of the transmission of rainfall data at each observation station.

The configuration of the embodiment of the present invention is configured as shown in FIG. The rain gauge 1 is a rainfall sensor for measuring rainfall.

The memory 2 is a memory for inputting and storing the data of the rain gauge 1, and the signal stored in the memory is transmitted via the transmitter 3.

The antenna 8 is an antenna that radiates transmission radio waves into the air. The clock oscillator 4 generates a clock signal for generating an ID signal and a transmission time signal, receives this clock signal in the internal clock 5, divides the original signal and converts it to hexadecimal, and outputs the hour, minute, A parallel time signal of seconds is created. The ID counter 41 receives the one-second signal from the internal clock 5 and creates a binary time signal.
When the transmission control signal is output, it is reset to 0.

The AND circuit 42 performs an AND operation on the status output signal of the memory 2 and the transmission control signal from the transmission time generator 6 and outputs the signal when both signals are present.

Therefore, if both signals are not transmitted, transmission from the transmitter 3 is not performed. The transmission time generation unit 6
This is for checking the set time against the time from the internal clock 5 and outputting a transmission control signal to the transmitter when the times match.

The operation of the embodiment will be described in more detail with reference to FIGS. The rain gauge 1 is a rain gauge placed outdoors and outputs data obtained by measurement to the observation apparatus.

Generally, the rain gauge outputs one pulse signal when there is a rainfall of 1 mm. This output is 1mm
It is performed every time.

The output is counted and stored in the memory 2 of the observation apparatus. Memory 2
Are two lines for outputting data and a status signal to the AND circuit 42. Data output A
Is the data for transmitting the rainfall data observed by the rain gauge 1 via the transmitter, and the status data B
Is a signal indicating that data to be transmitted is stored in the memory.

Therefore, when no rainfall is observed in the rain gauge, the status data B is not output, and the output of the AND circuit 42 does not occur. Transmitter 3
Is not transmitted unless a transmission control signal from the transmission time generator 6 and a status signal from the memory are output.

Even when data is transmitted, the transmission is stopped when the transmission of the data stored in the memory is completed. Therefore, the transmission time is a very short packet transmission. The clock oscillator 4 is an oscillator having relatively high frequency stability, and the internal clock 5 is operated by the output signal.

As a result, the internal clock 5 generates a parallel time signal of hour, minute and second.

At the same time, in order to record the data generation time in the memory, an ID signal, which is a binary counting time signal, is generated via the ID counter 41 and sent to the memory 2. This ID signal is also stored. Now, assuming that the time output from the internal clock 5 matches the time preset in the transmission time generator 6, the transmission time generator 6 outputs a transmission control signal and outputs
A signal is output to the D circuit 42.

If the status output from the memory 2 is on, since the data to be transmitted is stored in the memory 2, the transmitter 3 is set to the transmission state.

At the same time, the data stored in the memory 2 is transmitted from the transmitter 3, and when the transmission of the stored data ends, the transmission stops. The transmission control signal is also sent to the ID counter 41 at the same time as being sent to the AND circuit 42, and resets the ID counter 41 to zero.

As a result, the ID counter 41 starts counting from zero again. The output of the GPS receiver 7 corrects the internal clock 5 every predetermined time.

Therefore, a plurality of observation devices can synchronize the time between the devices. The transmission time set in advance in the transmission time generator 6 does not overlap the transmissions of the plurality of observation devices in consideration of the time lag of the internal clock 5 occurring until the next time correction of each observation device. There is a guard time. With the behavior described above,
Each observation device can perform stable transmission without causing a transmission time lag that causes transmission to overlap, and as a result, transmission radio waves from the observation device do not overlap.
In addition, the flowchart shown in FIG. 5 includes a step 501 of determining whether or not the observation data of the rain gauge is output, a step of counting the output, and a step 503 of storing the ID signal.
A step 504 of determining whether a transmission control signal is output, a step 505 of determining whether there is transmission data in the memory, a step 506 of transmitting data from the transmitter to the memory, and a step 506 of transmitting data from the memory. The method includes a step 507 for determining whether the transmission is completed, and a step 508 for stopping the transmission state when the transmission is completed. still,
Since the transmission control signal is generated at regular intervals regardless of the presence or absence of rainfall, step 502 is added to form a loop circuit.

[0058]

The effects of the present invention are as follows.

The first effect is that since the transmission times of the data of a plurality of rainfall observation devices are respectively determined, there is no simultaneous transmission of the observation devices, so that no measurement data is lost. The reason is that the transmission time of each observation device is set separately so that it does not overlap, and the internal clock of each observation device is corrected using the signal from GPS so that the time does not shift. Because it can always be transmitted at the correct time.

The second effect is that a change in rainfall can be measured without fail. The reason is that in the conventional self-starting transmission method, the transmission time is irregular, so that two or more observation devices may transmit, and in such a case, data is lost.

As a result, even if the accumulated rainfall can be measured by the subsequent reception, the rainfall rate at the time of the missing (rainfall / hour)
Can no longer be measured. However, since there is no missing data in this observation device, the rainfall rate can be reliably measured.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram illustrating features of an observation device according to the present invention.

FIG. 2 is an explanatory diagram showing an embodiment when the observation device of the present invention is used.

FIG. 3 is a diagram illustrating setting of a guard time at which a plurality of observation stations transmit at an accurate time without overlapping.

FIG. 4 is a detailed block diagram of the observation device of the present invention.

FIG. 5 is a flowchart showing the operation of the observation station of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rain gauge 2 memory 3 transmitter 4 clock oscillator 5 internal clock 6 transmission time generator 7 GPS receiver 21 to 30 observation station # 1 to # 10 34 reception station 35 GPS 41 ID counter 42 AND circuit

Claims (6)

[Claims] 1. A rainfall observation system having a plurality of sets of rain gauges for measuring rainfall and a transmitter for transmitting a pulse signal from the rain gauge to a receiving station, a memory for inputting data of the rain gauge, an ID signal, A clock oscillator that generates a clock signal for generating a transmission time signal; an internal clock that receives the clock signal and creates a parallel time signal of hours, minutes, and seconds; and a 1-second signal from the internal clock. An AND circuit that performs an AND operation on an ID counter for generating a binary time signal, a status output signal of a memory, and a transmission control signal from a transmission time generation unit, and outputs when both signals are present; A transmission time generation unit that compares the set time in the unit with the time from the internal clock, and outputs a transmission control signal to the transmitter when the times match, and sets the internal clock at predetermined time intervals. Rainfall observation system of the synchronous self-starting method characterized by having a a GPS receiver to correct. 2. A synchronous self-starting method further comprising means for setting a guard time before and after the transmission time of each observation device in order to eliminate the influence of a time shift occurring during timing correction by the GPS signal. Rainfall observation system. 3. A rainfall observation method for transmitting a pulse signal from a rainfall gauge to a receiving station, wherein the rainfall gauge outputs observation data; and a timing data indicating a time at which the output is counted and data is generated. A step of storing a certain ID signal together; a step of determining whether a transmission control signal is output from the transmission time generation unit; a step of determining whether transmission data exists in the memory; In addition, when a transmission control signal is output, a step of transmitting data from the transmitter to the memory, and a step of stopping the transmission state when the transmission of the stored data ends, a step of synchronous self-starting. Method of rainfall observation. In the transmitting step of each of the observation devices, a transmission time is assigned in advance so that each observation station transmits in order, and the transmission radio wave from the observation device is transmitted by synchronizing time between the observation devices. A synchronous self-starting rainfall observation method that performs stable transmission without duplication. 5. The step of outputting a transmission control signal from the transmission time generation section is performed when a time preset in the transmission time generation section and a time output by an internal clock coincide with each other. Rainfall observation method. 6. The transmission control signal is sent to an AND circuit at the same time as being sent to an AND circuit.
And the ID counter restarts counting from 0. The method of synchronous self-starting rainfall observation, further comprising the step of: