Abstract
COMPASS is an indigenously developed Chinese global navigation satellite system and will share many features in common with GPS (Global Positioning System). Since the ultra-tight GPS/INS (Inertial Navigation System) integration shows its advantage over independent GPS receivers in many scenarios, the federated ultra-tight COMPASS/INS integration has been investigated in this paper, particularly, by proposing a simplified prefilter model. Compared with a traditional prefilter model, the state space of this simplified system contains only carrier phase, carrier frequency and carrier frequency rate tracking errors. A two-quadrant arctangent discriminator output is used as a measurement. Since the code tracking error related parameters were excluded from the state space of traditional prefilter models, the code/carrier divergence would destroy the carrier tracking process, and therefore an adaptive Kalman filter algorithm tuning process noise covariance matrix based on state correction sequence was incorporated to compensate for the divergence. The federated ultra-tight COMPASS/INS integration was implemented with a hardware COMPASS intermediate frequency (IF), and INS's accelerometers and gyroscopes signal sampling system. Field and simulation test results showed almost similar tracking and navigation performances for both the traditional prefilter model and the proposed system; however, the latter largely decreased the computational load.
Highlights
The global COMPASS or Beidou II is a second generation Chinese satellite navigation system being developed from its first generation predecessor, Beidou I, which was a regionally-based system [1,2].By the end of 25 February 2012 eleven COMPASS satellites have been launched successfully.Currently, COMPASS is providing reliable position services to the south and southeast coastland ofChina and south Asian areas [3].Like a GPS receiver, the COMPASS receiver faces the paradoxical situation in optimising the carrier-tracking loop bandwidth to guarantee anti-jamming capability and dynamics adaptation simultaneously, i.e., anti-jamming capability needs a narrow bandwidth while dynamics adaptation needs a wider one [4,5]
This paper has proposed a simplified prefilter model and a corresponding adaptive Kalman filter algorithm to replace the traditional one
(2) COMPASS B3 RF module is responsible for down-converting B3 RF signal into intermediate frequency (IF) signal and providing driving clock for FCFR-PCIe9801 data sampling card
Summary
The global COMPASS or Beidou II is a second generation Chinese satellite navigation system being developed from its first generation predecessor, Beidou I, which was a regionally-based system [1,2]. Carrier and code tracking and INS corrections are performed simultaneously in a single integrated Kalman filter, as shown in Figure 1 [13]. This paper has proposed a simplified prefilter model and a corresponding adaptive Kalman filter algorithm to replace the traditional one. The remainder of this paper is organized as follows: Section 2 introduces a commonly used prefilter and integrated navigation filter models in federated GPS/INS architecture, Section 3 introduces the simplified prefilter model and corresponding adaptive Kalman filter algorithm, in addition, the COMPASS/INS integrated navigation filter model is proposed. Before introducing the simplified adaptive prefilter model of ultra-tight COMPASS/INS integration, a brief introduction is given on traditional prefilter and integrated navigation model of federated GPS/INS integration. Prefilter and integrated navigation filter are two kernel components of this architecture
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
