Attitude determination using dedicated and nondedicatedmultiantenna GPS sensors

We show that the use of nondedicated Global Positioning System (GPS) sensors to determine the attitude parameters of a vessel yields the same level of performance as the use of a dedicated multiantenna receiver, namely an agreement of the order of 0.1° (1σ). The test platform is a survey launch operating at cruising speeds of 10 to 15 kt. The dedicated multiantenna receiver is a four-antenna Ashtech 3DF unit, while the nondedicated sensor array consists of three NovAtel GPSCard^TM receivers. The approach used to resolve the relative carrier phase integer ambiguities between the antennas is discussed and the use of antenna baseline constraints is analyzed. A least-squares procedure which utilizes all the position information from the antennas for the estimation of the attitude parameters and their accuracy is presented. The attitude determination results from the two configurations tested are intercompared