JPH05205075A - System and method for collecting data - Google Patents

Abstract

PURPOSE:To exactly identify buoys without superimposing transmitted data by always correcting the timers of respective buoys for accurately keeping them while utilizing the time signals of radio or the like, and transmitting data based on this time. CONSTITUTION:A buoy 1 is provided with a GPS(Global Positioning System) receiver and a data transmitter, the respective buoys flow over a water zone and are distributed at respective spots, and time and position information is accurately obtained by receiving radio waves from a GPS satellite 2. The respective buoys 1 transmit own position information at the designated time. Concerning ht GPS observation method, the positions are measured by receiving radio waves from plural artificial satellites. Accurate time synchronizing signals are continuously transmitted from the satellites, and the positions to be measured can be judged immediately. A data collector 3 receives position data transmitted from the respective buoys 1. The respective buoys 1 are identified according to the difference of receiving time, and the current position or the moving speed of each buoy 1 is measured by analyzing the received data.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to collecting data from multiple locations. In particular, it relates to a system and method for collecting data collected by a plurality of mobile bodies.

[0002]

2. Description of the Related Art When data is transmitted from many points,
On the receiving side, the data is superposed, so that it becomes impossible to determine. Therefore, it is conceivable to change the transmission frequency for each point or use time division transmission.

[0003]

Problems to be Solved by the Invention The prior art has the following problems. <B> If the transmission frequency is different for each point, it is necessary to change the frequencies of both the transmitter and the receiver, which causes a problem that the system becomes complicated. <B> When time-division transmission is used, there is a problem in that the transmission time at each transmission point is incorrect and the data received at the reception side is superimposed.

[0004]

It is an object of the present invention to accurately set the time on the sending side when transmitting data from a plurality of points in a time division manner,
An object of the present invention is to provide a system and method for accurately receiving data at each point.

[0005]

SUMMARY OF THE INVENTION The present invention is a data collection system for collecting data from a plurality of moving bodies in a collecting apparatus, and a receiving apparatus which is loaded on each moving body and receives time data from radio time, Means for correcting the internal time of the mobile body by the time data obtained by being loaded on each mobile body and received, and transmitting the data collected by the mobile body loaded on each mobile body at each assigned transmission time A data collection system and a collection method, which include a transmission device and a collection device that identifies and collects data transmitted from each mobile body according to a reception time.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. The outline of the embodiment will be described with reference to FIG. <A> The buoy 1 is equipped with a GPS receiver and a data transmitter for transmitting position information. Each buoy is discharged to the water area, dispersed at each point, and receives radio waves from the GPS satellites 2 to obtain accurate time and position information. Each buoy transmits its position information at the designated time. In addition, GPS (Gl
Observing system (obal Positioning System) is a method in which a plurality of artificial satellites are placed so as to surround the earth, and the radio waves transmitted from these satellites are received for positioning. Since accurate time synchronization signals are always transmitted from these satellites, there are advantages that the accurate time can be known and the position to be measured can be instantaneously determined.
Further, since GPS uses ultra-short waves, the straightness of radio waves is remarkably good, and stable and highly accurate positioning is ensured.

<B> Data Collection Device The data collection device 3 receives the position data transmitted from each buoy 1. Each buoy is identified by the difference in the received time. By analyzing the received data, it is possible to measure the current position and moving speed of each buoy.

A data transmission method will be described with reference to FIGS. <A> Position Detection Method The method of detecting position information using GPS satellites is roughly classified into independent positioning and interferometric positioning. FIG. 2 shows a block diagram of a detection device for interference positioning. First, the GPS antenna 10 simultaneously receives radio waves from a plurality of (four or more) satellites. Then, by decoding the navigation message (satellite orbit, transmission time, etc.) of each satellite, a geometrically rough three-dimensional position can be known. The circuits that execute this are the pseudo distance measurement circuit 14 and the calculation circuit 15. However, this alone cannot provide accurate (eg, error within a few centimeters) data due to factors such as transmission time error, satellite orbit error, and radio wave propagation error due to the atmosphere. Therefore, the phase difference of the carrier waves of the radio waves sent from each satellite is measured, and the accuracy of the wavelength level (example: 1/1 of the wavelength)
Three-dimensional position is detected by (measurement up to 00). This operation is performed by the carrier wave regenerating circuit 12 and the phase integrating circuit 13, and constitutes a circuit for interference positioning. That is, GP
The radio wave received by the S antenna 10 is amplified by the amplification circuit 11, the phase data is extracted by the carrier reproduction circuit 12 and the phase integration circuit 13, and stored in the storage device 16. Further, the signal from the amplifier circuit 11 is input, and the position trajectory information is extracted by the pseudo distance measurement circuit 14 and the calculation circuit 15 and stored in the storage device 16. The stored information is sent to the data collecting device, where the receiving position can be known accurately.

<B> Time Correction Method The navigation message received from the GPS satellite includes time data called Z count. If this data is used to correct the time, high accuracy (example: 1/100)
It can be corrected in seconds. Further, using this corrected time, the arrival time of the code signal sent from each satellite is measured for four satellites, and X,
It is possible to correct the clock with high accuracy (eg, 1 microsecond or less) by solving four unknowns, which are Y and Z unknowns plus the correction value of the clock, by simultaneous equations. Further, since the above processing is always executed to calculate the three-dimensional coordinates, it is not necessary to add special processing to obtain the time correction data. The signal thus extracted from the calculation circuit 15 is input to the time correction circuit 17,
The internal clock 18 of the buoy 1 is corrected. To send the buoy location information, set the preset time 1 for each buoy.
Go to 9. That is, the set time 19 given to each buoy and the corrected internal clock 18 of the buoy are constantly compared by the comparison circuit 20, and when they match, a trigger signal is output and the position stored in the storage device 16 is stored. The data is transmitted by the transmitter 21. Therefore, since the released buoys can transmit position data at extremely accurate timing, radio waves of the same frequency can be used in time division multiplexing.

<C> Receiving data of the data collecting device The data collecting device receives the data transmitted by the buoys, which are discharged and distributed at the respective points, as data as shown in FIG. For example, since data is transmitted from each buoy on a carrier wave of the same frequency every minute, the data collection device 3 side receives the data at the preset time of each buoy,
The data of each buoy is analyzed. The transmission set time of each buoy may be arbitrarily determined according to the number of buoys and the amount of transmission data, and it is also possible to cyclically transmit in minutes or hours.

In the above embodiment, the transmission data is GP.
Although it is the position information from the S satellite, the transmission data is not limited to the position information, and any information such as water temperature and temperature may be used. Further, the information source is not limited to the buoy, but may be information from a moving body such as a balloon or an automobile. Further, the time synchronization signal of GPS radio waves is used to correct the buoy clock, but it may be a radio time signal such as a radio or television time signal.

[0012]

Since the present invention is as described above, the following special effects can be obtained. <B> Since the system has a simple configuration, it is possible to collect wide area information quickly and accurately. <B> Only using the same frequency as the carrier wave,
Since the time division transmission is possible, the device becomes simple. <C> Since it is not necessary to put numbers such as buoys in the transmission data, the transmission data amount can be small and the data transmission efficiency can be improved. <D> Since it is not necessary to include numbers such as buoys in the transmitted data, it is difficult to analyze even if received by a third party (effect of data confidentiality protection). <E> Since only one frequency is used, this will reduce the congestion of the radio band.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of an embodiment according to the present invention.

FIG. 2 is a block diagram for obtaining position information and time information from GPS satellites.

FIG. 3 is a diagram showing collection data received by a data collection device.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shuichi Nishizawa 1-25-1 Nishishinjuku, Shinjuku-ku, Tokyo Within Taisei Corporation (72) Inventor Sancho Matsumoto 1-25-1 Nishishinjuku, Shinjuku-ku, Tokyo Within Taisei Construction Co., Ltd.

Claims (3)

[Claims] 1. A data collection system for collecting data from a plurality of moving bodies in a collecting device, and a receiving device loaded on each moving body and receiving time data from wireless time; and loaded on each moving body and receiving data. Means for correcting the internal time of the moving body based on the time data obtained by the above, a transmitting device loaded on each moving body and transmitting the data collected by the moving body at each assigned transmission time, and each moving unit according to the reception time A data collection system, comprising: a collection device that identifies and collects data transmitted from the body. 2. A data collection method for collecting data from a plurality of mobile bodies, the method comprising: obtaining time data from wireless time by a receiving device arranged in each mobile body; The step of correcting the internal time of each mobile unit by time data, the step of transmitting the data received by each mobile unit at the transmission time assigned to each mobile unit, and the data collection side A data collection method characterized by identifying and collecting data of. 3. A data collecting system for collecting data from a plurality of buoys in a collecting device, the GPS receiving device being loaded on each buoy, receiving time data and position data from GPS satellites, and being loaded on each buoy. A means for correcting the internal time of the buoy based on the time data received and received, a transmitter for loading the data collected at each buoy and transmitting the collected data at each assigned transmission time, and a transmission device for each buoy according to the reception time And a collecting device for identifying and collecting the collected data, and a data collecting system.