Introduction to GNSS Geodesy

Clement A. Ogaja

GNSS geodesy, or geodesy by means of global navigation satellite systems (GNSS), plays an important role in the accurate and precise locating of points and infrastructure anywhere on Earth. Take, for example, a modern application such as high-accuracy GNSS-supported augmented reality (AR) in the construction industry. Without accurate reference systems and precise GNSS geodetic positioning, it would be hard to produce accurate views of underground utilities that enable engineers in the field to see the true location(s) of buried pipes and conduits to avoid damage and safety issues. Even with the best of 3D software models, a low-accuracy GNSS data stream would cause the 3D model to move about on screen, making it impossible to confidently show where the virtual representation of an object should truly appear in the AR display’s field of view. This is just one of the many examples of GNSS geodesy’s role in modern-day applications. This book introduces a selection of key elements of GNSS geodesy to help understand the concepts of achieving high precision from GNSS data, on the basis of the existing models and strategies. Discussions are provided with the assumption that the reader is primarily interested in understanding the key concepts and elements, and pertinent references are provided throughout as necessary for further reading and consultation. Being an introductory book, it is intended as a complementary reference and guide for those involved in the fields of high-precision positioning with GNSS, including, but not limited to, students, researchers, scientists, engineers, and professionals in the fields of geodesy, geosciences, geomatics, engineering, geoinformatics, surveying, navigation, GNSS product and software development, and all related areas and applications.