Removing rfi in clp data

feb14

How the rfi is removed
Looking at the results:
Summary
Warning:


     rfi removal in clp data  can take advantage of the decoding step when trying to remove frequency dependent rfi.
clp processing for each 10 second block of data (1000 ipps) consists of:

    If rfi occurs with a finite bandwidth in an ipp:


How the rfi is removed: (top)

    RFI can  be removed by  clipping large signals in the frequency domain (prior to decoding). The process is:
 

Looking at the results:  (top)

    Two 5 MHz bands were accumulated for 10 seconds centered at 435.5 and 439.5 MHz. The 10sec block chosen has:


Height vs frequency images:

The table below shows the averaged  data processed with no clipping, clipping with 0 replacement, clipping with noise replacement:

channel:cfr
No clipping
clip
replace with 0's
clip
replace with noise
chan1: 435.5
 noclip.gif
clipWithzeros.gif
clipWithNoise.gif
chan2:439.5
noclip.gif
clipWithZeros.gif
clipWithNoise.gif



Average spectra over all heights and 10 seconds. (top)

     The plots show the average spectra for the 10 seconds and all heights (.ps) (.pdf):


Signal to noise with rfi in and outside of the plasma line freq range (top)

    The below plots show a 10 second average spectrum at a particular height that includes the plasma line. Some have rfi outside of the plasma line, other plots have rfi on top of the plasma line. The data was taken from   t1193_03feb2014_015_001

plots comparing the 10 second average spectrum at a given height  (.ps) (.pdf)



Mike's plots (top)





Summary:  (top)

processing: x101/atm/clpshs/cliprfi/chknseclip.pro shsclp.pro


 
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