JPS5834792B2 - Earthquake telemeter method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention improves the transmission of earthquake motion by limiting the type of information to be transmitted among various information on earthquake motion to the extent necessary to determine the epicenter and magnitude of the earthquake. This paper relates to an earthquake telemeter system that saves the number of lines required or makes effective use of low-quality lines.

A typical example of a conventional seismic telemeter system is shown in Figure 1.

Figure 1 shows a case where there are three observation points and one of them is used as a base to transmit seismic motion to the base station.

In FIG. 1, 1a to 3a are observation points provided in the observation area, and 1a also serves as a base directly connected to a base station.

4a is a base station located in an area remote from the observation area.

Lines 5a to 7a transmit seismic motion signals.

The observation areas where observation points 1a to 3a are provided are usually uninhabited and selected as inconvenient remote areas in the mountains to avoid the influence of constant tremors.

On the other hand, the base station 4a is also where an organization that requires information regarding earthquakes is located, and is usually installed at a sub-site.

Therefore, the line 7a between the observation point 1a and the base station 48 tends to have a longer distance.

The seismic motion signal that must be transmitted through the line 7a is a total of nine components of the three components of the vertical motion, north-south motion, and east-west motion of the earthquake motion obtained at each of the observation points 1a to 3a.

-For example, three components of seismic motion can be sent over one telephone line.

According to this example, line 7a requires three lines.

If three long-distance lines such as the line 7a are required, it may be difficult to secure the number of lines.

Or, even if you manage to secure one, there are drawbacks such as the expense increasing and making it impossible to maintain it.

The purpose of the present invention is to eliminate these drawbacks by reducing the number of telemeter lines by limiting the content of the seismic motion to be transmitted to the extent that the purpose of earthquake observation can be achieved.This will be described in detail below. explain.

FIG. 2 shows the first embodiment of the present invention, in which the number of observation points is 3.
This is the case for points.

1 is an observation base in the observation area.

2 and 3 are observation points, 4 is a base station, 5 to 7 are telemeter transmission lines, 8 is a geometer vertical motion converter (hereinafter referred to as ■ converter), and 9 is a seismometer north-south motion converter (hereinafter referred to as N converter), 10
11 is a signal regulator (hereinafter referred to as regulator); 12 is a transmitter; 13 is a receiver; 14 is a switch; 15 is an earthquake detector; 16 is a feeder, 1
7 is a receiver, and 18 is a processing device.

Next, the operation of the first embodiment will be explained.

At observation points 2 and 3, ground motion is detected by the converter 8, N converter 9, and E converter 10, converted into an electrical signal, amplified by the regulator 12, subjected to signal adjustment such as F waves, and transmitted. The signal is modulated by the quantizer 12 so that it can be sent to the transmission line.

The output of the meter 12 at observation point 2 is transmitted through the transmission line 5, and the output of the meter 12 at observation point 3 is transmitted through the transmission line 6.
It is sent to receiver 13 of observation base 1.

At observation base 1, in addition to the ground motion signals sent from observation points 2 and 3, the ground motion at observation base 1 is detected by converter 8, N converter 9, and E converter 10; You can also obtain the signal adjusted by .

The receiver 13 of the observation base 1 demodulates the modulated signals from the observation points 1 and 2 and supplies the ground motion signal to the switch 14.

The ground motion signal at the observation base 1 is also supplied to the switch 14 from the regulator.

Three components of vertical motion, north-south motion, and east-west motion of ground motion at observation base 1, observation points 2, and 3, nine components in total, are constantly supplied to the input of the switch 14.

The switch 14 normally sends three components of vertical motion to the feeder 16.

The transmitter 16 modulates the signal so that it can be sent to the transmission line.

This modulated signal is sent to the base station 4 through the transmission line 7, demodulated by the receiver 17, and guided to the processing device 18.

The processing device 18 performs processing, recording, etc. related to earthquake motion.

Another output of the transmitter 16 is sent to the earthquake determination device 15 at the observation base 1.

The 15 human-powered earthquake detectors are normally operated at observation base 1, observation point 2,
Since this is the vertical motion component of the ground motion signal in step 3, if an earthquake occurs and seismic waves reach this observation network, the initial motion will cause the amplitude of the vertical motion component of the ground motion signal to increase within the time determined by the size of the observation network. increase all at once.

The earthquake detector 15 constantly monitors signs of such earthquakes, and if an earthquake is determined, the processor 18 of the base station 4 measures the time of occurrence, push/pull, amplitude, period, etc. for each vertical motion component. After some time, switch 1
A control signal is supplied to 4.

This is because once the processing device 18 measures these, there is no need to continue monitoring the vertical motion component for the purpose of measuring the epicenter and magnitude.

The switch 14 switches from the previous three vertical motion components to six horizontal motion components and sends them to the feeder 16.

Since the feeder 16 changes the previous three-component input into a six-component input, the modulation content is switched internally.

Since the number of components is doubled, the maximum transmission frequency for vertical motion component transmission is approximately 1 for horizontal motion component transmission.
/2.

After switching, the base station 4 is transmitted from the data transmitter 16 via the transmission line 7.
The six horizontal motion components are transmitted to the receiver 17.

Receiving the seismic motion signal of six horizontal motion components from the receiver 17, the processing device 18 measures the S wave generation time, the S liquid volume large amplitude, the period, the earthquake end time, and the like.

On the other hand, the earthquake determiner 15 determines the end time of the earthquake, generates a control signal, drives the switch 14, and restores normal vertical motion three-component transmission.

In the first embodiment described above, since the observation network consisting of observation base 1 and observation points 2 and 3 has a side length of approximately several hundred to several thousand meters, the transmission line 5 or 6 may be privately operated. If it is possible and a dedicated line for the Telegraph and Telephone Public Corporation is available, this may be used.

On the other hand, the transmission line 7 connecting the observation base 1 and the base station 4 is
Generally speaking, the distance will be longer.

-As an example, the numbers would be in the tens or hundreds.

It is extremely inefficient both economically and socially to provide such long-distance private lines, as well as to use a large number of lines dedicated to the Telephone and Telecommunications Public Corporation.

The first embodiment has the advantage that the number of long-distance transmission lines can be reduced from three lines to one line, as described above.

In the first embodiment described so far, the observation base 1 normally sends out the vertical motion component, but it switches to the north-south motion component and the east-west motion component and sends it out based on a switching signal from the earthquake detector 15. However, as shown in FIG. 3, it is also possible to configure the observation base 1 to switch to only the north-south motion component and send it out.

It is rare for an earthquake motion to have no north-south motion component and only have an east-west motion component.

On the other hand, it does not completely lack an east-west dynamic component.

Therefore, even with this configuration, it is possible to transmit the vertical motion component at all times and the horizontal motion component at the time of switching, producing the same effect as in the first embodiment.

The same effect can be obtained by using the east-west motion component instead of the north-south motion component.

As a third embodiment, as shown in Fig. 4, observation base 1
, the absolute value of the square root of the sum of the square of the output of the N converter and the square of the output of the E converter is created by the square root circuit 20, and this is configured to be sent as a horizontal motion component while being switched to a vertical motion component. You can also do that.

Since the processing device 18 of the base station 4 also performs the same processing as the square peace phallus circuit in order to obtain the magnitude, there is no problem in processing this before transmission.

Another piece of information we are trying to obtain from horizontal motion is the time of shear wave oscillation, but this is also clearer from the sum-of-squares root circuit output than from looking at each component of the horizontal motion.

Therefore, even if the configuration is as shown in FIG. 4, it is equivalent to transmitting the vertical motion component at all times and the horizontal motion component at the time of switching.

The present invention has the advantage that the number of transmission lines can be reduced because the vertical motion component and horizontal motion component are switched and transmitted in a timely manner in the signal transmission of seismic motion. Lines can be used economically.

Furthermore, since the present invention detects the presence or absence of an earthquake at an observation base, there is also the effect that there is extremely little possibility that information about the observation point will be detected erroneously.

[Brief explanation of drawings]

FIG. 1 is an observation network diagram illustrating a conventional seismic telemeter system, and FIGS. 2, 3, and 4 are detailed explanatory diagrams of the present invention. 1...Observation base, 2...Observation point, 3...Observation point,
4...Base station, 5-7...Telemeter transmission line,
8...■ converter, 9...N converter, 10...E converter, 11...signal conditioner, 12...feeder, 13
...Receiver, 14...Switcher, 15...Earthquake detector, 16...Transfer device, 17...Receiver, 18...
Processing device, 19...Switcher, 20...Automatic sum square root circuit.

Claims (1)

[Scope of Claims] 1 Earthquake information at a large number of observation points provided in a predetermined observation area is provided at a point remote from the predetermined observation area via a predetermined observation point or a separate observation base. In the telemetry method, the observation base always monitors the vertical motion component of the observation point and sends it to the base station, and when the observation base senses the occurrence of an earthquake, the observation base An earthquake telemeter system characterized by stopping the transmission of vertical motion components to the base station and transmitting horizontal motion components to the base station. 2. The earthquake telemeter system according to claim 1, characterized in that a north-south motion component or an east-west motion component is used as the horizontal motion component. 3. An earthquake as set forth in claim 1, characterized in that the horizontal motion component is the square root of the sum of the square of the value of the north-south motion component and the square of the value of the east-west motion component. Telemeter method.