Packet radio from the ISS with GNU Radio and USRP

On July 10, 2010, I was listening to the linear transponder downlink of VO-52 when I suddenly noticed a very strong peak about 50 kHz below. I checked Gpredict and found out that it was the APRS downlink from the International Space Station RS0ISS on 145.825 MHz. Thanks to the flexible GNU Radio framework and the USRP, I could easily receive both satellites at the same time as shown on the video below.

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