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Submitter: Albert van Duin
Description: The proof-of-concept prototype of the Phased Array Antenna for SAR (PAASAR) project is currently being tested in the assembly area. The aim of the project is to develop and test an active antenna that can simultaneously receive Search And Rescue (SAR) signals relayed by at least four different Galileo navigation satellites. These SAR signals (not to be confused with synthetic aperture radar) may be transmitted by distress beacons on boats, aircraft and handhelds. By measuring the time of arrival of these four (or more) signals, and using the known locations of the satellites, the origin of the distress signal can be determined.

Presently, SAR ground stations use steerable dish antennas to track satellites as they move across the sky, with each dish tracking only a single satellite at a time. Obviously, it is much more efficient to track all the visible satellites with a single antenna. PAASAR uses ASTRON/JIVE UniBoard technology to combine the signals received by 50 antenna elements to form multiple independent beams that track different satellites simultaneously. Thus creating a solid-state ground station without any moving parts!

We have moved PAASAR to the ASTRON premises because the 3rd harmonic of UMTS and television saturated our LNA (amplifier) at our previous test location in Amsterdam. Since the RF environment near Dwingeloo is much less hostile, we soon hope to capture our first satellite signal. After we have finished doing some basic tests, and some Front End (FE) upgrades in the lab, we will mount the FE on the frame that is already being placed next to Huisje West at ASTRONs Open Area Test site.

During the next weeks you will see Dion Kant(*) and Bart Peeters of Ursa Minor working on this project, assisted by two Zoran's from the Spanish company TTI. They are all partners in the PAASAR project. For more information and the full list of project partners, see https://artes.esa.int/projects/paasar

What makes this project special is that technology and know-how that was developed for astronomical research (e.g. the LOFAR and SKA radio telescopes) can also be applied to save lives.

(*) Dion Kant has of course been involved in developing phased array technology as an ASTRON employee in the past. It is good to see him again.
Copyright: Bart Peeters, Ursa Minor B.V.
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