J Geod (2014) 88:363–376 DOI 10.1007/s00190-013-0688-2 ORIGINAL ARTICLE GNSS antenna array-aided CORS ambiguity resolution Bofeng Li · Peter J. G. Teunissen Received: 19 August 2013 / Accepted: 12 December 2013 / Published online: 31 December 2013 © Springer-Verlag Berlin Heidelberg 2013 Abstract Array-aided precise point positioning is a mea- surement concept that uses GNSS data, from multiple anten- nas in an array of known geometry, to realize improved GNSS parameter estimation proposed by Teunissen (IEEE Trans Signal Process 60:2870–2881, 2012). In this contribution, the benefits of array-aided CORS ambiguity resolution are explored. The mathematical model is formulated to show how the platform-array data can be reduced and how the vari- ance matrix of the between-platform ambiguities can profit from the increased precision of the reduced platform data. The ambiguity resolution performance will be demonstrated for varying scenarios using simulation. We consider single- , dual- and triple-frequency scenarios of geometry-based and geometry-free models for different number of antennas and different standard deviations of the ionosphere-weighted constraints. The performances of both full and partial ambi- guity resolution (PAR) are presented for these different sce- narios. As the study shows, when full advantage is taken of the array antennas, both full and partial ambiguity resolution can be significantly improved, in some important cases even enabling instantaneous ambiguity resolution. PAR widelan- ing and its suboptimal character are hereby also illustrated. B. Li (B ) · P. J. G. Teunissen College of Surveying and Geo-Informatics, Tongji University, Shanghai, People’s Republic of China e-mail: bofeng_li@tongji.edu.cn; bofeng_li@163.com B. Li · P. J. G. Teunissen GNSS Research Centre, Curtin University, Perth, Australia P. J. G. Teunissen Geoscience and Remote Sensing, Delft University of Technology, Delft, Netherlands e-mail: p.teunissen@curtin.edu.au Keywords Global navigation satellite system (GNSS) · Integer ambiguity resolution (IAR) · Continuously operating reference station (CORS) · Array-aided precise point positioning (A-PPP) · Full ambiguity resolution (FAR) · Partial ambiguity resolution (PAR) 1 Introduction Integer ambiguity resolution is the key to high-precision GNSS applications. It enables the transformation of the ambiguous carrier phases to ultra-precise pseudoranges, thus making high-precision parameter estimation possible. The success of ambiguity resolution depends on the strength of the underlying GNSS model. The weaker the model, the more data needs to be accumulated before ambiguity resolution can be successful and the longer it therefore takes before one can take advantage of the ultra-precise carrier signals. Clearly, the aim is to shorten the time to convergence, preferably zero, thereby enabling truly instantaneous GNSS, integer ambigu- ity resolved, parameter estimation. In CORS network applications, fast and successful reso- lution of the ambiguities is important as it enables improved availability of the network provided ambiguity-fixed parame- ter outputs, such as the ionospheric delays. Between-station ambiguity resolution is usually based on data of stations equipped with a single antenna only. In this contribution, we study the potential improvements that can be realized when stations would be equipped with an array of antennas instead of only a single antenna. This A-PPP concept, pro- posed in Teunissen (2012), is a measurement concept that uses GNSS data, from multiple antennas in an array of known geometry, to realize improved GNSS parameter estimation. Although we focus on ambiguity resolution in this contribu- tion, integrity improves, since with the known array geom- 123