Astraea: Anonymous and Secure Auditing Based on Private Smart Contracts for Donation Systems

Many regions are in urgent need of facial masks for slowing down the spread of COVID-19. To fight the pandemic, people are contributing masks through donation systems. Most existing systems are built on a centralized architecture which is prone to the single point of failure and lack of transparency. Blockchain-based solutions neglect...

On the Efficacy of Compact Radar Transponders for InSAR Geodesy: Results of Multiyear Field Tests

Compact and low-cost radar transponders are an attractive alternative to corner reflectors (CRs) for interferometric synthetic aperture radar (InSAR) deformation monitoring, datum connection, and geodetic data integration. Recently, such transponders have become commercially available for C-band sensors, which poses relevant questions on...

Mode S Transponder Comm-B Capabilities in Current Operational Aircraft

Mode S surveillance allows air traffic controllers to interrogate certain information from aircraft, such as airspeeds, turn parameters, target altitudes, and meteorological conditions. However, not all aircraft have enabled the same capabilities. Before performing any specific interrogation, the surveillance radar must acquire the transponder...

Software-defined testbed for next generation navigation transponders

This paper presents a software-defined testbed to perform hardware-in-The-loop test of miniaturized coherent transponders. Such a setup has been designed to minimize the access threshold for future users, heavily relying on available open source applications and commercial hardware, targeting future coherent transponders for interplanetary...

First analysis of C-band ECR transponders for InSAR geodesy

Well-identifiable reference benchmarks are important in SAR interferometry to enable linking between different measurement techniques, or to enable datum connection between the local InSAR datum and Terrestrial Reference Systems. As corner reflectors for C-band are rather large, weather sensitive, and difficult to maintain over time frames of...

InSAR datum connection using GNSS-augmented radar transponders

Deformation estimates from Interferometric Synthetic<br/>Aperture Radar (InSAR) are relative: they form a ‘free’<br/>network referred to an arbitrary datum, e.g. by assuming a reference<br/>point in the image to be stable. However, some applications<br/>require ‘absolute’ InSAR estimates, i.e. expressed in<br/>a well-defined terrestrial...

Geodetic network design for InSAR: Application to ground deformation monitoring

For the past two decades, interferometric synthetic aperture radar (InSAR) has been used to monitor ground deformation with subcentimetric precision from space. But the applicability of this technique is limited in regions with a low density of naturally-occurring phase-coherent radar targets, e.g. vegetated nonurbanized areas. Third-party end...