Variometric approach for real-time GNSS navigation: First demonstration of Kin-VADASE capabilities

The use of Global Navigation Satellite Systems (GNSS) kinematic positioning for navigational applications dramatically increased over the last decade. Real-time high performance navigation (positioning accuracy from one to few centimeters) can be achieved with established techniques such as Real Time Kinematic (RTK), and Precise Point Positioning (PPP). Despite their potential, the application of these techniques is limited mainly by their high cost. This work proposes the Kinematic implementation of the Variometric Approach for Displacement Analysis Standalone Engine (Kin-VADASE) and gives a demonstration of its performances in the field of GNSS navigation. VADASE is a methodology for the real-time detection of a standalone GNSS receiver displacements. It was originally designed for seismology and monitoring applications, where the receiver is supposed to move for few minutes, in the range of few meters, around a predefined position. Kin-VADASE overcomes the aforementioned limitations and aims to be a complete methodology with fully kinematic capabilities. Here, for the first time, we present its application to two test cases in order to estimate high rate (i.e., 10 Hz) kinematic parameters of moving vehicles. In this demonstration, data are collected and processed in the office, but the same results can be obtained in real-time through the implementation of Kin-VADASE in the firmware of a GNSS receiver. All the Kin-VADASE processing were carried out using double and single frequency observations in order to investigate the potentialities of the software with geodetic class and low-cost single frequency receivers. Root Mean Square Errors in 3D with respect to differential positioning are at the level of 50 cm for dual frequency and better than 1 meter for single frequency data. This reveals how Kin-VADASE features the main advantage of the standalone approach and the single frequency capability and, although with slightly lower accuracy with respect to the established techniques, can be a valid alternative to estimate kinematic parameters of vehicle in motions.