GPS device for Measuring wave height and current direction and speed and GPS system for measuring wave height and current direction and speed

• US 20030189513A1
• Filed: 04/02/2003
• Published: 10/09/2003
• Est. Priority Date: 04/05/2002
• Status: Active Grant

• Current Assignee: Japan Aerospace Exploration Agency
• Original Assignee: National Aerospace Laboratory Of Japan
• Inventors: Yamaguchi, Isao, Kasai, Tokio, Harigae, Masatoshi
• Granted Patent: US 6,847,326 B2
• Time in Patent Office: Days
• US Class Current: 342/357.06
• CPC Class Codes: G01C 13/002 Measuring the movement of open water
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 19/35 Constructional details or hardware or software details of the signal processing chain
• CPC Class Codes: G01S 19/396 Determining accuracy or reliability of position or pseudorange measurements

Abstract

The present invention provides a GPS device for measuring the wave height and current direction and speed, which is capable of accurately measuring the wave height (height of the waves) and current direction and speed (tidal current) in any point on the sea, ocean, lake, or marsh, and to a system using such a device. The GPS receiver 2 of the GPS device 1 for measuring the wave height and current direction and speed processes the GPS signals received with the GPS antenna 3 and measures the three-dimensional position of antenna 3. The three-dimensional position data are recorded by the data recording unit 4 connected to the GPS receiver 2. When the floating body 5 having those devices 2-4 installed thereon floats on the sea or ocean, it moves together with the waves and tidal current in the present location. The software 7 for conducting high-pass filter processing and smoothing processing is installed in the data processing unit 6, and the data on the wave height and current direction and speed are output, while the errors are being removed from the three-dimensional position data recorded in the data recording unit 4.

Claims

1. A GPS device for measuring the wave height and current direction and speed, comprising:

a floating body capable of floating on a fluid such as seawater, fresh water, and the like;

a GPS antenna for receiving GPS signals;

a GPS receiver for processing said GPS signals received by said GPS antenna and measuring the three-dimensional position; and

a data recording unit for recording the position data relating to said three-dimensional position measured by said GPS receiver, wherein

said GPS antenna, said GPS receiver, and said data recording unit are installed on said floating body.

2. The GPS device for measuring the wave height and current direction and speed according to claim 1, wherein a transmitter for transmitting said position data is installed on said floating body.

3. The GPS device for measuring the wave height and current direction and speed according to claim 1, wherein a data processing unit is installed on said floating body for processing said position data extracted from said data recording unit and calculating the wave height and current direction and speed in the point where said floating body is floating.

4. The GPS device for measuring the wave height and current direction and speed according to claim 3, wherein said data processing unit conducts high-pass filter processing of said position data for extracting only the wave height components present in a high-frequency region in order to calculate said wave height, and conducts smoothing processing of said position data for extracting only the current direction and current speed components in order to calculate said current direction and current speed.

5. The GPS device for measuring the wave height and current direction and speed according to claim 4, wherein said data processing unit is capable of setting a cut-off frequency of said high-pass filter and smoothing time of said smoothing processing for removing the errors contained in said position data.

6. The GPS device for measuring the wave height and current direction and speed according to claim 3, wherein a transmitter for transmitting the computed data relating to said wave height and current direction and speed calculated by said data processing unit is installed on said floating body.

7. A GPS system for measuring the wave height and current direction and speed comprising:

a GPS device for measuring the wave height and current direction and speed, comprising;

a floating body capable of floating on a fluid such as seawater, fresh water, and the like;

a GPS antenna for receiving GPS signals;

a GPS receiver for processing said GPS signals received by said GPS antenna and measuring the three-dimensional position;

a data recording unit for recording the position data relating to said three-dimensional position measured by said GPS receiver; and

a transmitter for transmitting said position data, said GPS antenna, said GPS receiver, said data recording unit, and said transmitter being installed on said floating body, and

a base station equipped with a receiver for receiving said position data transmitted from said transmitter and a data processing unit for processing said received position data and calculating the wave height and current direction and speed in the point where said floating body is floating.

8. The GPS system for measuring the wave height and current direction and speed according to claim 7, wherein a processing software for conducting said high-pass filter processing and smoothing processing of said position data is installed in said data processing unit for calculating said wave height and current direction and speed.

9. A GPS system for measuring the wave height and current direction and speed comprising:

a GPS device for measuring the wave height and current direction and speed, comprising;

a floating body capable of floating on a fluid such as seawater, fresh water, and the like;

a GPS antenna for receiving GPS signals;

a GPS receiver for processing said GPS signals received by said GPS antenna and measuring the three-dimensional position;

a data recording unit for recording the position data relating to said three-dimensional position measured by said GPS receiver;

a data processing unit for processing said position data and calculating the wave height and current direction and speed in the point where said floating body is floating; and

a transmitter for transmitting the computed data relating to said wave height and current direction and speed,

said GPS antenna, said GPS receiver, said data recording unit, said data processing unit and said transmitter being installed on said floating body, and

a base station equipped with a receiver for receiving said computed data transmitted from said transmitter.

10. The GPS system for measuring the wave height and current direction and speed according to claim 9, wherein a processing software for conducting said high-pass filter processing and smoothing processing of said position data is installed in said data processing unit for calculating said wave height and current direction and speed.