Title:
METHOD FOR MEASURING INERTIAL ALTITUDE
Document Type and Number:
Japanese Patent JP3711538
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To stably and smoothly measure an inertial altitude by avoiding the stepwise change in the standard altitude when the standard altitude is switched to a GPS altitude from a pressure altitude.
SOLUTION: An inertial altitude correcting part 1 comprises a negative feedback loop having a first feedback circuit composed of a multiplying circuit 14, a switching circuit 15, an integration circuit 16 and an adder circuit 17, and a second feedback circuit composed of a multiplying circuit 13. The inertial altitude 103 is generated by doubly integrating acceleration 101 in the vertical direction. A GPS altitude bias estimating part 2 is formed as a negative feedback loop which estimates and maintains the altitude error 111 of the GPS altitude 112 to the inertial altitude 103 output from the integration circuit 11 when the pressure altitude 104 is selected as the standard altitude. A standard altitude selecting part 3 is provided with an altimeter judging circuit 7 which determines the effective degree of each measuring altitude by a pressure altimeter 5 and a GPS receiver 6, and a switching circuit 22 which selects and outputs the standard altitude.
Inventors:
Masaki Yamada
Application Number:
JP2002188623A
Publication Date:
November 02, 2005
Filing Date:
June 27, 2002
Export Citation:
Assignee:
Japan Aviation Electronics Industry Co., Ltd.
International Classes:
G01C21/00; G01C5/00; G01C5/06; G01S19/48; G08G1/0969; (IPC1-7): G01C5/00; G01C5/06; G01C21/00; G01S5/14
Domestic Patent References:
| JP63026529A | ||||
| JP11211472A | ||||
| JP2001091635A | ||||
| JP2000283775A | ||||
| JP7034339U | ||||
| JP1503170A |
Attorney, Agent or Firm:
Shinsuke Ozeki