System for ascertaining height as related to an established reference

• US 6,317,079 B1
• Filed: 04/18/2000
• Issued: 11/13/2001
• Est. Priority Date: 04/18/2000
• Status: Expired due to Fees

• Current Assignee: US Army Corps of Enginerrs As Represented By The Secretary of The Army
• Original Assignee: US Army Corps of Engineers (U.S. Department Of Defense)
• Inventors: Shannon, Brian F.
• Primary Examiner(s): Blum, Theodore M.
• Application Number:
  US09/551,860
• Time in Patent Office: 574 Days
• Field of Search: 342/357.08, 342/357.09, 342/357.1, 701/215
• US Class Current: 342/357.75
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 19/39 the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
• CPC Class Codes: G01S 19/44 Carrier phase ambiguity resolution; Floating ambiguity; LAMBDA [Least-squares AMBiguity Decorrelation Adjustment] method

Abstract

A preferred embodiment permits the safe navigation of a channel or harbor by a ship. A preferred embodiment includes a ship-borne system having a first global positioning system (GPS) receiver and a second fixed reference station with a GPS receiver. Both GPS receivers have GPS signal receiving antennas. Earth orbiting satellites of the GPS maintain communication at both locations via the two receive antennas. A broadcast radio transmitter at the reference station transmits a received GPS signal to the ship-based GPS antenna for receipt by the ship'"'"'s separate radio receiver and processing by a computer. Using known navigation chart information on the water depths within a body of water, channel or harbor, known marine surveyor data, including the phase center of the ship-borne GPS receive antenna, and the two separately received GPS signals, the ship'"'"'s keel clearance referenced to a known chart datum is calculated at one second intervals.

Claims

1. A system for ascertaining height relative to at least one chart datum, comprising:

at least one reference first GPS receiver, said reference first GPS receiver in operable communication with at least one GPS satellite transmitting at least one first signal containing GPS data;

at least one first communications device at least transmitting at least one second signal containing GPS data received from said at least one reference first GPS receiver;

at least one second GPS receiver, having at least one antenna having a known phase center and appurtenant to a vehicle having at least one extremity generally vertically oriented with respect to at least one horizontal plane represented by said at least one chart datum, said at least one second GPS receiver in operable communication with at least one GPS satellite for receiving said at least one first signal;

at least one second communications device, appurtenant to said vehicle,

for at least receiving said at least one second signal;

at least one computer, having at least one input and at least one output, incorporating at least one database and having connecting paths to allow operable communication with said at least one second communications device, said at least one first GPS receiver and said at least one second GPS receiver; and

at least one monitoring device for receiving at least one said at least one outputs from said computer,

wherein, said database comprises vertical reference data in relation to said at least one chart datum for at least one horizontal position relative to said reference at least one GPS receiver,

wherein, said at least one GPS satellite comprises at least four satellites each of which is transmitting at least one said at least one first signal, and

wherein said GPS data are Real Time Kinematic (RTK) data that are carrier phase differential processed by said computer to provide an accurate record over time of the height of said at least one extremity relative to said at least one chart datum.

2. The system of claim 1 in which said first communications device is a transmitter compatible with said second communications device and said second communications device is a receiver, appurtenant to said vehicle and compatible with said first communications device.

3. The system of claim 2 in which said vehicle is a marine vessel having said computer appurtenant thereto,

wherein said height is the height of water referenced to at least one chart datum in a navigable location, and

wherein said computer provides at least one indication of said height of water in relation to at least one of said extremities.

4. A vehicle, having extremities, at least parts of which extremities extend in a generally vertical orientation with respect to a horizontal plane represented by at least one chart datum, and at least a part of a system for ascertaining height in relation to said chart datum, said system comprising:

at least one reference first GPS receiver, said reference first GPS receiver in operable communication with at least one GPS satellite transmitting at least one first signal containing GPS data;

at least one first communications device at least transmitting at least one second signal containing GPS data obtained from said at least one GPS satellite via said at least one reference first GPS receiver;

at least one second GPS receiver, having at least one antenna having a known phase center and appurtenant to said vehicle, said at least one second GPS receiver in operable communication with at least one GPS satellite for receiving said at least one first signal;

at least one second communications device, appurtenant to said vehicle, for at least receiving said at least one second signal; and

at least one computer, having at least one input and at least one output, incorporating at least one database and having connecting paths to allow operable communication with said at least one second communications device, said at least one first GPS receiver and said at least one second GPS receiver; and

at least one monitoring device for receiving at least one said at least one outputs from said computer,

wherein, said database comprises vertical reference data in relation to said at least one chart datum for at least one horizontal position relative to said reference at least one GPS receiver,

wherein, said at least one GPS satellite comprises at least four satellites each of which is transmitting at least one said at least one first signal, and

wherein said GPS data are Real Time Kinematic (RTK) data that are carrier phase differential processed by said computer to provide an accurate record over time of the height of said at least one extremity relative to said at least one chart datum.

5. The vehicle of claim 4 in which said first communications device is a transmitter compatible with said second communications device and said second communications device is a receiver, appurtenant to said vehicle and compatible with said first communications device.

6. The vehicle of claim 4 in which said vehicle is a marine vessel, wherein said height is the height of water referenced to at least one chart datum in a navigable location.

7. A system for ascertaining height in relation to at least one chart datum, comprising:

at least one first GPS receiver having at least one antenna having a known phase center, said at least one first GPS receiver appurtenant to a vehicle having at least one extremity generally vertically oriented with respect to at least one horizontal plane represented by said at least one chart datum, and in operable communication with at least one GPS satellite;

at least one first communications device, appurtenant to said vehicle, for receiving at least one signal and transmitting at least said at least one first signal;

at least one reference second GPS receiver, said reference second GPS receiver in operable communication with at least one GPS satellite;

at least one second communications device at least receiving said at least one first signal containing GPS data obtained from said at least one GPS satellite via said at least one first GPS receiver;

at least one computer, incorporating at least one database and having connection paths to allow operable communication with said at least one second communications device and said at least one second GPS receiver; and

at least one monitoring device, appurtenant to said vehicle, in operable communication at least with said at least one second communications device,

wherein, said database comprises vertical reference data in relation to said at least one chart datum for at least one horizontal position relative to said reference at least one GPS receiver,

wherein, said at least one GPS satellite comprises at least four satellites each of which is transmitting at least one said at least one first signal, and

wherein said GPS data are Real Time Kinematic (RTK) data that are carrier phase differential processed by said computer to provide an accurate record over time of the height of said at least one extremity relative to said at least one chart datum.

8. The system of claim 7 in which said vehicle is a marine vessel and said computer is remote therefrom, said computer providing, via said first and second communications device, at least one indication of said height to said monitor, wherein said height is the height of water referenced to at least one chart datum in a navigable location.

9. The system of claim 7 in which said first communications device is a transmitter compatible with said second communications device and said second communications device is a receiver, appurtenant to said vehicle and compatible with said first communications device.

10. A vehicle, incorporating at least a part of a system for ascertaining height in relation to at least one chart datum, said system comprising:

a first GPS receiver located at a fixed reference position, said first GPS receiver in operable communication with at least one GPS satellite transmitting at least one first signal containing GPS data;

a first communications device at least transmitting at least one second signal containing GPS data obtained from said at least one GPS satellite via said first GPS receiver;

a second GPS receiver appurtenant to said vehicle, said second GPS receiver in operable communication with at least one GPS satellite, via at least one antenna having a known phase center, said at least one antenna appurtenant to said vehicle;

a second communications device appurtenant to said vehicle and at least receiving said at least one second signal; and

a computer appurtenant to said vehicle, employing memory to incorporate at least one database and having connection paths to allow operable communication with said second communications device and said second GPS receiver,

wherein, said database comprises vertical reference data in relation to said at least one chart datum for at least one horizontal position relative to said reference at least one GPS receiver,

wherein, said at least one GPS satellite comprises at least four satellites each of which is transmitting at least one said at least one first signal, and

wherein said GPS data are Real Time Kinematic (RTK) data that are carrier phase differential processed by said computer to provide an accurate record over time of the height of said at least one extremity relative to said at least one chart datum.

11. The vehicle of claim 10 in which said vehicle is a marine vessel, wherein said height is the height of water referenced to at least one chart datum in a navigable location.

12. The vehicle of claim 10 in which said first communications device is a transmitter for at least line-of-sight communications at a frequency compatible with said second communications device and said second communications device is a receiver for at least line-of-sight communications at a frequency compatible with said first communications device.