Dynamic GPS Attitude Determining System (ADS) for Marine Applications, Concept Design and Developmental Test Results

Debra L. Deifes, Leopold C. Fan and Charles E. Rodgers

Abstract:	Under contract with the US Coast Guard, Adroit Systems, Inc. is developing a low cost, marine, GPS based Attitude Determiniq System (ADS). The USCG will use the sys- tem for: navigation, hydrographic surveying, ice breaker navigation, and positioning buoys or other objects of&et from a GPS antenna. A demonstration system has been constructed and tested. Results were obtained under dynamic conditions using as few as two GPS satellites, The system will consist of integrated commercial off-the- shelf components. Adroit will integrate a single board com- puter (SBC) with three Magnavox Engine Receivers and Ball Communication System’s antennas. The SBC will be programmed with Adroit proprietary attitude detetminiq software. The Coast Guard development effort focused on develop- ing methods to improve the attitude accuracy achieved with prior ADS systems. Key carrier phase error reduction tech- niques were investigated, including: selecting the optimal satellite constelhuion, reducing multipath, and using more than one baseline for data redundancy. The Coast Guard ADS effort utilized a new antenna arrangement and ADS software. The new baseplane was designed to reduce multipath affects. The software incor- porated a satellite selection algorithm to allow the best sat- ellite constellation available to be used. The attitude software algorithms were improved by employing numeri- cal optimization techniques and eliminating the cycle ambiguity problem which allows attitude to be determined with only 2 satellites. This paper describes the system design including the inno- vative antenna baseplane assembly and attitude determin- ing algorithms. Accuracy improvement techniques will be presented and the results shown. Results of the real-time static and dynamic tests will be presented as well as fbture ADS applications for this system.
Published in:	Proceedings of the 1993 National Technical Meeting of The Institute of Navigation January 20 - 22, 1993 Parc 55 Hotel San Francisco, CA
Pages:	569 - 578
Cite this article:	Deifes, Debra L., Fan, Leopold C., Rodgers, Charles E., "Dynamic GPS Attitude Determining System (ADS) for Marine Applications, Concept Design and Developmental Test Results," Proceedings of the 1993 National Technical Meeting of The Institute of Navigation, San Francisco, CA, January 1993, pp. 569-578.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In