At the present time, commercially available geodesy instruments, e.g., the Macrometer (TM) Interferometric Surveying System, are capable of measuring baselines of one kilometer or less to three-dimensional accuracies of approximately 3 mm. These instruments use signals of the NAVSTAR Global Positioning System (GPS) satellites which broadcast in the one-to-two GHz frequency range. Multipath interference is the primary cause of short baseline measurement uncertainty which is therefore inversely proportional to signal frequency. Steinbrecher Corporation proposes to investigate the feasibility of greatly increasing the accuracy of short baseline vector measurements by receiving signals from millimeter-wave satellites as well as those from the GPS. The proposed Phase I objective is to develop data reduction algorithms for simulating realistic measurement scenarios with the goal of achieving 100 micrometer three-dimensional accuracy on baselines up to one kilometer long. Experimental instrumentation would be constructed and tested during Phase II. The Phase I effort would build on Steinbrecher Corporation's pioneering development efforts which have established the current state of the art of precision satellite-based geodesy. Macrometer (TM) is a trademark of Aero Service Division, Western Geophysical Corporation of America, Houston, Texas. The potential commercial application as described by the awardee: The benefit of this effort is the development of an instrument capable of bringing 100 micrometer accuracy to (vector) measurements of baselines ranging from one meter to over one kilometer in length.
