Fast Phase-Only Positioning with Triple-Frequency GPS

In this contribution, we study the phase-only ambiguity resolution and positioning performance of GPS for short baselines. It is well known that instantaneous (single-epoch) ambiguity resolution is possible when both phase and code (pseudorange) data are used. This requires, however, a benign multipath environment due to the severe effects...

An efficient implementation of fixed failure-rate ratio test for GNSS ambiguity resolution

Ambiguity Resolution (AR) plays a vital role in precise GNSS positioning. Correctly-fixed integer ambiguities can significantly improve the positioning solution, while incorrectly-fixed integer ambiguities can bring large positioning errors and, therefore, should be avoided. The ratio test is an extensively used test to validate the fixed...

GNSS integer ambiguity estimation and evaluation: LAMBDA and Ps-LAMBDA

Successful integer carrier-phase ambiguity resolution is crucial for high precision GNSS applications. It includes both integer estimation and evaluation. For integer estimation, the LAMBDA method has been applied in a wide variety of GNSS applications. The method’s popularity stems from its numerical efficien-cy and statistical optimality....

Precise and faster GNSS signal direction of arrival estimation

This paper proposes a precise and fast direction of arrival estimation method using Global Navigation Satellite System (GNSS) carrier phase measurements. Single-epoch, single-satellite integer cycle ambiguities are reliably resolved by making use of constraints and taking advantages of antenna arrays. The algorithm shows good robustness in cases...

The future of single-frequency integer ambiguity resolution

The coming decade will bring a proliferation of Global Navigation Satellite Systems (GNSSs) that are likely to enable a much wider range of demanding applications compared to the current GPS-only situation. One such important area of application is single-frequency real-time kinematic (RTK) positioning. Presently, however, such systems lack real...

Uniqueness and nonuniqueness of the GNSS carrier-phase compass readings

In this contribution we analyse the possible nonuniqueness in the least-squares solution of the GNSS carrier-phase compass model. It is shown that this lack of uniqueness may manifest itself in the fixed baseline estimator and therefore in the GNSS compass readings. We present the conditions under which nonuniqueness occurs and give explicit...

Fast precise GPS positioning in the presence of ionospheric delays

In many geodetic (surveying) applications positions of points in the terrain need to be determined with high precision (cm-accuracy or even better). The Global Positioning System (GPS) is very suitable for this purpose. High positioning accuracy is in principle feasible when a relative measurement setup is used and in the processing procedure...