Patent ID: 6317079
Filing Date: 2001-11-13
Classification: G01S

Abstract:
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; andat 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, andwherein 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.