NAVLAS - Improved GNSS Positioning Solution via Integration of Information Products from Laserscanning Data
Based on the combined processing of the datasets in the domain of the raw data and derived information products correlation parameters will be extracted. They show the interdependence between vegetation induced shading effects and positioning signal quality.
Related to LiDAR data specific algorithms were developed to derive relevant forest parameters for signal blockage. They aimed at the derivation of information products on the vertical distribution of intercepted forest surfaces, the vertical canopy length and other parameters up to a single tree level and to build the basis for the calculation of a differential forest volume model.
Innovative aspects of the project comprised the adaptation of a LiDAR processing software to airborne and terrestrial LiDAR data. Therefore algorithms were developed, which allow the extraction of forest density and the derivation of further signal blockage and forestry relevant parameters in a test site close to Feldkirch in the province of Vorarlberg.
- Vertical distribution of intercepted forest surfaces
- Crown length
- Topography of the forest ground
- Forest density
- Tree height These information layers were used to calculate a differential forest volume model based on cuboids of a defined size representing the vegetation density from the ground to the top of the forest.
The combination of the information products based on LiDAR data and GNSS measurements lead to a new knowledge base for the development of GNSS receivers.
In particular this comprised:
- A strategy of precise tuned signal acquisition and signal tracking ability for GNSS receivers to improve signal maintenance
- An improved relation between position accuracy and signal availability
With the project NAVLAS a structure and a code independent model of a receiver software was established. Based on the integrated usage of information layers from laserscanning data and GNSS signals this structure can build a programming basis. Receiver developers can use the model for a software implementation of a new generation of GNSS receivers.
Laserdata GmbH - Frederic Petrini-Monteferri