One way to distinguish between satellite and meteor echoes is by simply listening. Meteors are longer-lasting warbling whistles. A more clear-cut approach is to plot the power spectrum of the radar echo as a function of time. Not only is the reflection brief, it is also Doppler shifted as the orientation of the satellite's velocity vector changes with respect to the radar transmitter. Dynamic spectrum showing Leonid meteor and satellite radar echoes This dynamic spectrum spans the first 11 seconds of the Leonid meteor echo WAV file discussed in the body of this article .
Power is displayed in false color.
Meteoroids move at much higher velocities than low Earth orbit satellites, so the Doppler shift from a meteoroid echo would be even greater than that of a satellite. However, it is not the fast-moving meteoroid that causes the radar echo. The radio signal bounces off the ionized air left behind when the meteoroid disintegrates in the atmosphere. As a result there is no observable Doppler shift in the meteor echo. The meteor echo appears in the dynamic spectrum as a nearly horizontal line exhibiting no drift in frequency.