Current State of Multi-constellation and multi-frequency Precise Point Positioning

Abstract

[EN] Precise Point Positioning is a standalone method to estimate the coordinates of a single GNSS receiver based on undifferenced observations and modelling all the effects present during the observation session by precise products. The reference system of the coordinates estimated will be the same as the satellite orbits used in GNSS data processing. Due to its accuracy, PPP satisfies all most of applications where GPS observations are used. In recent years, the interoperability of new global navigation satellite systems (referred to as multi-GNSS) has driven the combination of observations coming from different satellite constellations. Multi-GNSS consists of the interoperability of at least two satellite constellations with some of their frequencies working in common. In this context, it has been essential to implement effective PPP algorithms to take advantage of the novelties presented by the different satellite navigation systems. As a consequence, some scientific software has been updated to support multi-frequency and multi-constellation GNSS data in PPP mode. Some of them are Bernese 5.2, RTKLIB, goGPS and PCUBE. The last one is being developed by the authors. This program implements two techniques for multi-GNSS data processing. One of them is based on a sequential filter and the other one is based on the Least Squares Approach. The purpose of this work is to study the capability and evaluation of multi-GNSS PPP performance along a whole day comparig the solutions estimated by different GNSS processing software. Special attention will be paid to the benefits introduced by new frequencies and services provided by the European System Galileo.