Airborne Gradiometry Error Analysis |
| |
| Authors: | Christopher Jekeli |
| |
| Institution: | (1) Division of Geodetic Science, Department of Geological Sciences, Ohio State University, 125 South Oval Mall, Columbus, OH 43210, USA |
| |
| Abstract: | Gravity gradiometry is one of the older methods of determining the Earth’s local gravitational field, but lies in the shadow
of more conventional static and moving-base gravimeter-based systems. While the static torsion balance appears to have been
relegated to the museum, support for the airborne and space-borne differential accelerometer (gradiometer) continues so as
to overcome limitations in spatial resolution and accuracy inherent in ordinary moving-base gravimetry. One airborne system
exists, building on 30 year old technology concepts, and new technologies (e.g., cold-atom interferometry) promise significant
improvements. Concomitant advances are required to measure accurately the angular velocity and angular acceleration of the
platform, which inseparably combine (in an absolute sense) with the Earth’s gravitational gradients. A numerical analysis
of instrument errors, with simulated aircraft dynamics, shows that navigation-grade gyros are just sufficient to account for
these effects in gradiometers with 1E/
sensitivity. More accurate instruments, with 0.1 E/
sensitivity, require commensurate sensitivity in the gyros, of the order of 0.01°/h/
= 1.5\times10−4 ° \
for typical survey aircraft dynamics. On the other hand, typical orientation errors in the platform, which are problematic
for vector gravimetry, are much less of a concern in gradiometry. They couple to the gradient signals and affect only the
very low frequencies of the total gradient error. |
| |
| Keywords: | airborne gravity gradiometry gradiometer error analysis angular rate errors |
| 本文献已被 SpringerLink 等数据库收录！ |
|
