LOFAR as a passive radar, part two

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In a 2008 daily image, Michiel Brentjens showed airplane reflections in a LOFAR measurement at 55 MHz. The airplane was illumitated by a Danish television transmittter located below the horizon. The movie above shows a similar result, but this time it is a reflection from an airplane illuminated by a radio transmitter at 88.8 MHz within line of sight. The transmitter signal itself is very strong and was suppressed with a spatial filter in order to make the reflection visble. The red cross points to the direction from which most of the received energy is originating, after applying the spatial filter. The observation was done using LOFAR Core Station CS021.