Joint SSC-SD-UNAVCO Proposal: Use of Global Positioning System (GPS) Phase Measurements to Improve Vertical Refractivity Profiles in the Boundary Layer.

摘要

LONG TERM GOALS. Our long term goal is to provide the Navy with a stand alone shipboard system that utilizes GPS signals for refractivity profiling of the marine boundary layer. OBJECTIVES. Our objective is to demonstrate a new method for refractivity profiling in the boundary layer for use in shipboard and land-based systems. APPROACH. We propose to develop and demonstrate a new method for refractivity profiling in the boundary layer using GPS phase data. SSC-SD has previously demonstrated a GPS Sounder that uses GPS amplitude data to estimate refractivity profiles in the marine boundary layer (Anderson, 1994). We propose to work with SSC-SD to enhance the GPS Sounder by including GPS phase measurements. Both the amplitude and phase of GPS signals received at low elevation angles are sensitive to refractivity effects. Accurate sensing of GPS phase at elevation angles of 20 degrees or more has been demonstrated by UNAVCO scientists (Ware et al., 1997). The combination of amplitude and phase measurements will place stronger constraints on the inferred refractivity profiles, providing improved reliability for use in a variety of shipboard and land-based tactical assessment systems that rely on refractivity profile data.