Improved ambiguity function method based on analytical resolution for GPS attitude determination

Wang, Yongquan; Zhan, Xingqun; Zhang, Yanhua

doi:10.1088/0957-0233/18/9/032

Cited by 35 publications

(32 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this contribution, we utilize the common clock technology to strengthen the GNSS model, which has been often used for GNSS short baseline attitude determination (GebreEgziabher et al 1998;Keong 1999;Alban 2004;Simsky et al 2005;Wang et al 2007). For this scheme, the accuracy of each component, especially the up component, can be improved .…”

Section: Introductionmentioning

confidence: 99%

Success rate improvement of single epoch integer least-squares estimator for the GNSS attitude/short baseline applications with common clock scheme

Chen

2014

Acta Geod Geophys

View full text Add to dashboard Cite

The sub-centimeter level relative positioning can be accomplished anytime and anywhere on Earth, provided that the integer ambiguities of the very precise Global Navigation Satellite System (GNSS) carrier-phase observables are correctly resolved. The Integer Least-Squares (ILS) estimator is known to be efficient and optimal for Integer Ambiguity Resolution (IAR) of the unconstrained GNSS model, and the stronger the model strength, the higher the success rate. In this contribution, we investigate the model strength of the common clock scheme, in which the two receivers of the short baseline feed a common clock and the cables have the same delay and many GNSS-based attitude/short baseline applications benefit from this approach. For this scheme, the clock biases between two receivers will be zero and can be omitted, and thus it has a stronger model strength and a higher success rate, compared with the non-common clock scheme. In this contribution, the well-known Ambiguity Dilution of Precision (ADOP), which captures the main characteristics of the ambiguity precision, is utilized to assess the model strengthening when the perfectly synchronized receivers are employed. The mathematical expression of the single epoch ADOP is deduced by the given design parameters, and thus the ADOP-based approximate ILS success rate can be easily computed with the specified measurement set-up which includes the number of available satellites and frequencies and the precision of observation. We focus on the success rate assessment of the common clock scheme for stand-alone, unaided, single-frequency, single epoch observation with only five visible satellites, since it is the most challenging case of GNSS relative positioning and in this case the performance of the employed ambiguity resolution method can be investigated effectively. Thus, one can predict whether or not the required performance will be obtained for the worst case.

show abstract

Section: Introductionmentioning

confidence: 99%

Success rate improvement of single epoch integer least-squares estimator for the GNSS attitude/short baseline applications with common clock scheme

Chen

2014

Acta Geod Geophys

View full text Add to dashboard Cite

show abstract

“…Therefore, its integer search still poses a major challenge (see e.g. Li et al 2004;Wang et al 2007). Hence, just as in case of surveying, the ambiguity function method for attitude determination is not yet widely used.…”

Section: Introductionmentioning

confidence: 99%

Integer least-squares theory for the GNSS compass

Teunissen

2010

J Geod

151

134

View full text Add to dashboard Cite

Global navigation satellite system (GNSS) carrier phase integer ambiguity resolution is the key to highprecision positioning and attitude determination. In this contribution, we develop new integer least-squares (ILS) theory for the GNSS compass model, together with efficient integer search strategies. It extends current unconstrained ILS theory to the nonlinearly constrained case, an extension that is particularly suited for precise attitude determination. As opposed to current practice, our method does proper justice to the a priori given information. The nonlinear baseline constraint is fully integrated into the ambiguity objective function, thereby receiving a proper weighting in its minimization and providing guidance for the integer search. Different search strategies are developed to compute exact and approximate solutions of the nonlinear constrained ILS problem. Their applicability depends on the strength of the GNSS model and on the length of the baseline. Two of the presented search strategies, a global and a local one, are based on the use of an ellipsoidal search space. This has the advantage that standard methods can be applied. The global ellipsoidal search strategy is applicable to GNSS models of sufficient strength, while the local ellipsoidal search strategy is applicable to models for which the baseline lengths are not too small. We also develop search strategies for the most challenging case, namely when the curvature of the non-ellipsoidal ambiguity search space needs to be taken into account. Two P. J. G. Teunissen Department of Spatial Sciences, Curtin University of Technology, Perth, Australia e-mail: p.teunissen@curtin.edu.au P. J. G. Teunissen (B) Delft Institute for Earth Observation and Space Systems (DEOS), Delft University of Technology, Delft, The Netherlands e-mail: p.j.g.teunissen@tudelft.nl such strategies are presented, an approximate one and a rigorous, somewhat more complex, one. The approximate one is applicable when the fixed baseline variance matrix is close to diagonal. Both methods make use of a search and shrink strategy. The rigorous solution is efficiently obtained by means of a search and shrink strategy that uses nonquadratic, but easy-to-evaluate, bounding functions of the ambiguity objective function. The theory presented is generally valid and it is not restricted to any particular GNSS or combination of GNSSs. Its general applicability also applies to the measurement scenarios (e.g. single-epoch vs. multiepoch, or single-frequency vs. multi-frequency). In particular it is applicable to the most challenging case of unaided, single frequency, single epoch GNSS attitude determination. The success rate performance of the different methods is also illustrated.

show abstract

“…For special real time case, the genetic algorithm is complicated than some AFM methods. Wang, et al studied an improved method using single-difference measurement of two antennas, which is a combination of an analytical resolution and the AFM [7]. The approach reduced the ambiguity, resolution time, and directly obtained the attitude (azimuth and pitch/roll), while some parameters (cable delay and clock bias, etc) should be estimated previously [8].…”

Section: Introductionmentioning

confidence: 99%

“…In this study, two receivers fed a common clock reference to eliminate the clock bias. As the baseline length was short, both ionospheric delay and tropospheric delay were cancelled [7]. The single-difference carrier phase (SDCP) measurement, which is the projection of baseline in the direction of LOS, can be expressed as ( )…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ambiguity Function Method Scheme for Aircraft Attitude Sensor Utilising GPS/GLONASS Carrier Phase Measurement

Jin¹,

Zhai²,

Wang³

et al. 2009

DSJ

View full text Add to dashboard Cite

When the receivers of GPS, GLONASS, COMPASS and other such systems are equipped with multiple antennas, they can give attitude information. Based on the difference carrier phase equations established in local level frame (LLF), a new algorithm is presented to resolve aircraft attitude determination problems in real-time. Presuming that the cycle integer ambiguity is known, the measurement equations have attitude analytical resolutions using single difference (SD) equations of two navigation satellites in-view. Similar with SD process, the double difference (DD) measurements are established and analysed. In addition, the SD and DD algorithms are capable of reducing the integer search space into some discrete point space and then the ambiguity function method (AFM) resolves the ambiguity function within the point solutions space. Therefore the procedures have very low computation, thus saving time. The hardware architecture has been realised using multiple GPS/GLONASS OEMs. The experimental results have demonstrated that the proposed approach is effective and can satisfy the requirement of real-time application in cases of GPS, and combined GPS, and GLONASS.

show abstract

Improved ambiguity function method based on analytical resolution for GPS attitude determination

Cited by 35 publications

References 13 publications

Success rate improvement of single epoch integer least-squares estimator for the GNSS attitude/short baseline applications with common clock scheme

Success rate improvement of single epoch integer least-squares estimator for the GNSS attitude/short baseline applications with common clock scheme

Integer least-squares theory for the GNSS compass

Ambiguity Function Method Scheme for Aircraft Attitude Sensor Utilising GPS/GLONASS Carrier Phase Measurement

Contact Info

Product

Resources

About