Strategies for high‐precision Global Positioning System orbit determination

Abstract

High‐precision orbit determination of Global Positioning System (GPS) satellites is a key requirement for GPS‐based precise geodetic measurements and precise low‐Earth orbiter tracking. We explore different strategies for orbit determination with data from 1985 GPS field experiments. The most successful strategy uses multiday arcs for orbit determination and incorporates fine tuning of spacecraft solar pressure coefficients and stochastic station zenith tropospheric delays using the GPS data. Average rms orbit repeatabilities for five of the GPS satellites are 1.0, 1.2, and 1.7 m in altitude, cross‐track, and downtrack components, when two independent 5‐day fits are compared. Orbits predicted up to 24 hours outside a 7‐day arc show average rms component differences of 1.5–2.5 m when compared to independent solutions obtained with a separate, nonoverlapping 5‐day arc. For a 246‐km baseline, with 6‐day arc carrier phase solutions for GPS orbits, baseline repeatability is 2 parts in 108 (0.4–0.6 cm) for east, north, and length components and 8 parts in 108 for the vertical component. For a 1314‐km baseline with the same orbits, baseline repeatability is about 2 parts in 108 for the north component (2.5 cm) and 4 parts in 108 or better for east, length, and vertical components. When GPS carrier phase is combined with pseudorange, the 1314‐km baseline repeatability improves further to 5 parts in 109 for the north (0.6 cm) and 2 parts in 108 for the other components (2–3 cm).

Fixed-Point GPS Observation of Crustal Movement Associated with the 1989 Seismic Swarm and Submarine Volcanic Activities off Ito, Central Japan.

“…1. Locations of the observation stations of the fixed-point GPS baseline determination network of NIED in central Japan (see Shimada et al, 1989 in detail). satellites are essential; an accuracy of 10-8 requires satellite position as accurate as 1m (Lichten and Border, 1987). At present we have no such means in Japan.…”

“…In the course of obtaining geodetic solutions, we did not utilize any specially devised techniques to resolve the phase ambiguities (Counselman and Abbot, 1989;Dong and Bock, 1989;Blewitt, 1989). It is mainly because of no practically available UPS fiducial tracking sites which are needed to obtain highly accurate orbital parameters (Lichten and Border, 1987). However, one of the most important features in the fixed-point continuous GPS networks consists in fixing the integer bias with ease (Bock and Shimada, 1990).…”

Recent Advances of Structures Monitoring and Evaluation Using GPS-Time Series Monitoring Systems: A Review

“…PPP analysis can be made either in local computers or using online services [63]. Currently, PPP processing is available in GPS software packages such as GIPSYOASIS [69] and BERNESE [70]. PPP was clearly developed for static applications and the dynamic analysis of structures, as presented in [21,24].…”

Seafloor Geodetic Approaches to Subduction Thrust Earthquakes

“…We employed the GIPSY OASIS II software (Lichten and Border, 1987) to simultaneously solve 1 to 10 Hz positions of the four antennas on the buoy relative to reference GPS stations on land, whose positions are calculated independently using Precise Point Positioning (PPP) analysis (Zumberge et al, 1997). We also use the KGPS software called IT (Interferometric Translocation) which has been used by the group of the Japan Coast Guard and the University of Tokyo (hereafter referred to as the JCG group).…”