Workshop in SAR for Geodesy

Thomas Gruber: SAR Positioning for Geodetic Applications

SAR offers new possibilities to observe absolute and relative 3D positions by collecting data in space from natural or artificial ground targets. This enables an easy and systematic surveying of the Earth surface for various geodetic applications. The paper presents some results from the project "Geodetic SAR for Height System Unification and Sea Level Research" and identifies possible other applications, where SAR positioning possibly could provide an added-value with respect to the existing techniques. The main focus of the paper is to develop ideas towards geodetic applications taking advantage of the existing SAR space infrastructure.

Christoph Gisinger: SAR positioning for geodetic applications revisited – Lessons learned from TerraSAR-X and Sentinel-1

Synthetic Aperture Radar (SAR) satellite missions can determine the 3-D position of persistent radar targets in a similar way as GNSS does with precise point positioning (PPP). This geodetic SAR method relies on the inherent timing and ranging capabilities of SAR sensors and it works well across different sensors when using dedicated ground infrastructure such as passive radar corner reflectors. But there are many aspects involved that have to be carefully considered in the processing such as precise orbit products, timing calibration of the SAR instruments, geometric fidelity of the SAR image products, or the correction of observation errors caused by atmospheric path delays and solid Earth deformation signals. The presentation will summarize the method and discuss the progress made with missions TerraSAR-X and Sentinel-1 over the past years.

Yngvar Larsen: Utilizing GNSS and CRs for InSAR Service Production & Validation: Challenges and Recommendations for Nationwide Implementation

We will discuss the challenges in developing and implementing nationwide InSAR services, with a focus on utilization of auxiliary information such as GNSS and CRs for production and validation. Our focus will be on InSAR services in Norway, Sweden, as well as the European Ground Motion Service. We will highlight critical elements of the process and provide recommendations based on our work so far.

Muriel Pinheiro: Sentinel-1 status and upcoming evolutions

The presentation will provide an overview of current status of the S1 mission and products as well as of latest and up-coming processor improvements and new products

Simon Schiller: Initial SAR positioning results from recently installed corner reflectors in Finland and Sweden

Corner reflectors (CRs) have been installed in Finland and Sweden to improve reference frame infrastructures. The advantage of this additional observing system is the possible densification of the national reference networks by combining relative and absolute SAR measurements with other observing techniques such as GNSS stations. This paper presents the first results of absolute 3D positioning of four selected CRs deployed in Finland and Sweden between 2019 and 2022. The absolute coordinates are calculated from Sentiel-1 C-band measurements by applying the Doppler equation in a least-squares fitting, taking into account sentinel-specific, geodynamic, and atmospheric corrections.

Marius Schlaak: 3D SAR Positioning Results — Experiences with Electronic Corner Reflectors

In the last years, an alternative to large passive corner reflectors became commercially available in form of smaller active radar transponders. In the frame of the ESA Baltic+ project ‘Geodetic SAR for Baltic Height System Unification’ 12 Electronic Corner Reflectors (ECRs) where operated over more than one year. 3D absolute positioning was performed for all stations for different time intervals using Sentinel-1 C-band Synthetic Aperture Radar data. For precise positioning measurements must be accurate and stable over long time periods. We present the accuracy and precision of the positioning results of the ECR stations and report the experiences made, processing the data of the ECRs around the Baltic Sea.

Chrishan Puwakpitiya Gedara: Performance analysis of the passive SAR corner reflector in Norrköping (East Sweden)

The presentation will be about exploiting the capabilities of the passive Interferometric Synthetic Aperture Radar (InSAR)-Corner Reflector (CR) installed in Norrköping using Single Look Complex (SLC), Sentinel 1A satellite images. Products generated from the Geodetic Corner Reflector Insar toolbox (GECORIS) such as time series and maps of signal-to-clutter ratio and temporal radar cross-sections, will be presented as an indication of the CR's performance. Furthermore, results from performing persistent scatterer interferometry (PSI) with reference to the location CR will also be presented.

Ramon Hanssen: INSAR Geodesy: TU Delft experience in datum connection and surface and infrastructure monitoring

Jyri Näränen: Current status of geodetic InSAR targets in Finland

FGI has hosted for 10 years a 1.5 -meter passive corner cube reflector, owned by DLR, at the Metsähovi Geodetic Research Station. In 2020 we received infrastructure funding from the Academy of Finland that allowed us to procure total of 11 additional passive CRs. I will discuss the current status of their installation at FINNREF permanent GNSS stations and some design aspects of the CRs being installed.

Otaranta 2
02150 Espoo
Tel. +358 20 1234 705
Radisson Blu Espoo Hotelli, Espoo
 
The hotel is located within walking distance from Aalto University campus. There’s also a metro station at the campus so public transportation both to Helsinki city centre and to the airport is easy to reach.

Runeberginkatu 2
00100 Helsinki
Tel. +358 20 1234 701
Radisson Blu Royal Hotelli, Helsinki

The hotel is located in the centre of Helsinki, in the Kamppi district. There are good connections by metro from Kamppi metro station to Aalto University in Espoo. Also easy to reach by train from the airport.