Flight Evaluation of a Locata-augmented Multisensor Navigation System
【摘要】:The Global Navigation Satellite System (GNSS) is a widely used technology for high positioning accuracy in many applications, including airborne mapping and sensor georeferencing. The integration of GNSS and an Inertial Navigation System (INS) is a critical navigation component in an airborne mapping system, because it can provide high update rate of solution, better accuracy and reliability, as well as being able to directly georeference the captured images. However, GNSS signals could be blocked or interfered with, and sometimes the satellite geometry may not be good enough for high accuracy and high reliability applications. Therefore the development of alternative, non-GNSS- based navigation solutions has attracted increased interest in situations where GNSS system availability cannot be guaranteed due to jamming or interference by spoofing attacks. Locata is a ground-based navigation system which can transmit ranging signals at several frequencies in the 2.4GHz Industrial, Scientific and Medical (ISM) radio bands. The integration of GNSS, INS and Locata can provide seamless precise positioning in all situations. This paper describes a flight test of a GNSS/INS/Locata triple-integrated system. The test was conducted in October 2011, during a flight from Bankstown Airport, Sydney, to Cooma Snowy Mountains Airport. The Locata pseudorange measurements were collected and post-processed to evaluate the overall navigation performance and analyse limitations of the integrated system.