Harmonics in the alfa/wapp system


    An idl routine was written to compute the possible harmonics in the alfa/wapp system (alfawappharm). The user specifies a sky center frequency as well as a list of possible input rfi frequencies (e.g. faa radar, aerostat radar, etc..). The program then steps through each section of the receiver chain creating harmonics of these frequencies and then removing any that get filtered out.  The result is a set of interfering spikes that end up in the final bandpass (the routine includes the fundamentals of any input rfi frequencies).
    The routine was run for the setup of a2010 (alfalfa with center frequency at 1385 Mhz). The plots show the harmonics created by the standard set of radars (.ps)  (.pdf):

    A 600 second drift scan take on 24feb06 was analyzed to demonstrate the typical birdies in the band (cfr=1385 Mhz). The rms/mean by channel shows the biridies in the band (.ps)  (.pdf): SEE ALSO:
processing: a2010/alfaharmonics.pro