GNSS navigation and positioning for the GEOHALO experiment in Italy

Abstract

GEOHALO is a joint experiment of several German institutes for atmospheric research and earth observation where exploring airborne gravimetry over Italy using the High Altitude and LOng Range (HALO) aircraft data is one of the major goals. The kinematic positioning of the aircraft, on which all remote sensing instruments are located, by Global Navigation Satellite System (GNSS) is affected by the characteristics of long-distance, long-time duration, and high-platform dynamics which are a key factor for the success of the GEOHALO project. We outline the strategy and method of GNSS data processing which takes into account multiple GNSS systems (GPS and GLONASS), multiple static reference stations including stations from the International GNSS Service (IGS) and the EUropean REFerence network (EUREF), multiple GNSSreceiving equipments mounted on the kinematic platform, geometric relations between multiple antennas, and assumptions of similar characteristic of atmospheric effects within a small area above the aircraft. From this precondition, various data processing methods for kinematic positioning have been developed, applied and compared. It is shown that the proposed method based on multiple reference stations and multiple kinematic stations with a common atmospheric delay parameter can effectively improve the reliability and accuracy of GNSS kinematic positioning.

Airborne Gravimetry of GEOHALO Mission: Data Processing and Gravity Field Modeling

“…The GNSS kinematic trajectories are based on multiple reference stations and multiple kinematic stations (two) as shown by He et al (). From the results, this method can effectively improve the reliability and accuracy of the kinematic relative positioning down to 1–2 cm accuracy.…”

“…The GEOHALO project includes different scientific experiments over Italy and adjacent regions over the Mediterranean: Global Navigation Satellite Systems (GNSS) navigation and positioning (He et al, ), GNSS reflectometry (Semmling et al, ), magnetometry, and laser altimetry (Scheinert, ). Airborne gravimetry is one of the main experiments of the GEOHALO project (Petrovic, Barthelmes, & Pflug, ).…”

GNSS Precise Kinematic Positioning for Multiple Kinematic Stations Based on A Priori Distance Constraints

“…The principle of the method of GNSS kinematic positioning with multiple kinematic and multiple reference stations [ 7 ] can be briefly described as follows: When double difference (DD) observation equations are formed, there is only one station that is used as a formal reference station. The other reference stations are processed formally as kinematic stations together with the actual moving kinematic stations, but, in contrast to the actual moving kinematic stations, a priori constraints based on the known station information are applied to other reference stations.…”

“…For this purpose, a method of GNSS kinematic positioning based on multiple kinematic stations with multiple reference stations [ 7 ] was in a first step updated to use the known distances among the multiple GNSS kinematic antennas as a priori constraints within the corresponding state parameters adjustment. In a second step, the data of the mentioned Baltic Sea shipborne campaign have been processed with and without these constraints.…”

Real Time Precise Relative Positioning with Moving Multiple Reference Receivers

“…Another class of studies mainly enhances the performance of float solutions of ambiguities in the positioning domain. Since multiple receivers mounted on the platform in an array of known geometry increases redundancy [ 20 ], these studies use multiple receiver configurations to strengthen the observational model [ 12 , 21 , 22 , 23 ]. In these studies, multiple receivers are utilized without considering the communication burden, and the baseline constraints are used to strengthen the position estimation model to improve the relative positioning performance using a stationary base station.…”