Doppler determination of satellite attitude
US5070338A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 1989 |
| Grant date | Dec 3, 1991 |
| Priority date | — |
| Expiry date | Aug 24, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S3/58
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining the attitude of a spacecraft without employing conventional attitude sensors, such as horizon sensors. A spin-stabilized spacecraft has an antenna mounted offset from the spin axis. The spacecraft is tracked over a substantial portion of its orbit from a ground (or tracking) station. A signal is transmitted from the spacecraft and received at the ground station. The spinning motion of the transmitting antenna causes the received frequency to oscillate sinusoidally due to Doppler shift acting on the transmitter-receiver range rate. The amplitude of the sinusoidal component of Doppler frequency shifts of the signals at several points along the orbit are used to determine the orientation of the spin axis. The attitude is adjusted as necessary, and thrusters are fired to move the spacecraft from the transfer orbit to the final orbit. The weight, cost and complexity of conventionl attitude sensors are eliminated from the spacecraft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.