Quick Guess - When the Pulse starts or stops you have a DC offset in I or Q signal.
Hello JohnnyM, The rabbit ears are the transient response of the channelizer bins (or offset frequency filters) to an input signal not in its bandwidth. Every filter sees the incoming signal and starts responding till it recognizes that it is not the signal the filter was designed to pass.. The transient occurs as the offset filters ring up (fill) and as they ring down (empty). The amplitude of the transients decrease with spectral distance from the input tone burst signal's center frequency.
Your explanation seems reasonable.So every complex baseband converter has this issue? They all will have an image that must be filtered, and it is offset from the FIR center by Fsample/2. Is there a way to control the amplitude? It seems if I play around with slightly different skirt shapes, there is some effect on on the shape of the distortion in the time domain, but I have failed to totally eliminate it.
Thanks, John M.
The rabbit ears can by modified by controlled transitions in the pulses... controlled rise time and controlled fall time... makes amplifies less efficient. This a classic problem in radar threat receivers and interference between hoppers and nearby center frequency receivers. see the attached pdf
Thanks for the explanation.