Potential accuracy of GNSS-based attitude determination
Radiolocation and radio navigation
Moscow Power Engineering Institute (National Research University), 14, Krasnokazarmennaja St., Moscow, 111250, Russia
The potential accuracy of the attitude determination of an object by means of global navigational satellite systems (GNSS) is considered in this article. GNSS is now widely used for a variety of technical problems, including the determination of orientation angles (attitude determination) of the object. There are two approaches to solve a problem of the attitude determination. The first approach is classic two-stage algorithms. The phase difference between signals received at spatially separated points is measured during the first stage. The information about angular orientation is extracted from phase shifts on second stage. Another approach is to use single-stage algorithms, immediately giving an estimate of the angular orientation. Such one-stage algorithm is presented in . The accuracy of attitude determination is characterized by a covariance matrix, which is described by quite complex Riccati equations. This fact does not allow getting required estimates of accuracy quickly enough. The purpose of this paper is to obtain general equations for calculating the potential (i.e. Cramer-Rao lower bound) estimation accuracy of GNSS-based attitude determination for an arbitrary number of reception points and their arbitrary location. Equations to describe attitude determination problem, GNSS signal model, likehood function are presented in the paper. Such equations are obtained and their analysis is given in the article. As shown in the article the increase of reception points quantity can decrease the most likely RMS of attitude determination. The RMS value of the orientation angle is approximately 1.5 arc. min. when 10 GNSS signals are received at 6 points with maximum distance between them 2 m.
Keywords:global navigational satellite systems, attitude determination, Cramer-Rao lower bound
Perov A.I., Harisov V.N. GLONASS. Printsipy postroeniya i funktsionirovaniya. (GLONASS. Principles of design and functioning), Moscow, Radiotekhnika, 2010, 800 p.
Perov A.I. Radiotekhnika, 2014, no. 9, pp. 97-105.
Perov A.I. Statisticheskaya teoriya radiotekhnicheskikh sistem (Statistical theory of radio systems), Moscow, Radiotekhnika, 2003, 400 p.