Solving the TLE lottery

TLEsWhen amateur radio satellites are initially deployed Two Line Elements (TLE) Keplerian orbital data sets for tracking the satellites are released by NORAD. Unfortunately they are only given object identifiers of A, B, C, D etc not satellite names. Some of the debris from the launch and deployment may also be given alphabetic identifiers. The problem is working out which of the 10 or more objects is the satellite you want to listen to.

Mike DK3WN has developed a simple solution to this perennial problem by using an SDR-IQ receiver and a bit of software.

In the case of Masat-1 he chose a high elevation pass (89 deg) where the doppler shift should be significant and recorded the complete pass with his SDR-IQ without doppler correction. With some software he simulated the entire pass with different TLE’s.

He then chose the TLE that best matched the doppler shift of the audio signal.

Read Mike’s full article with pictures on his website at