The setup:

• ch tx,receiver  using crr2 centered at 430 Mhz.
• coded long pulse program run with 440 usec pulse, 10 millisecond ipp.
  
• Rdev setup:
• 160 Mhz clock, decimate by 5: 32 Mhz Bw, 16 bits output, data  rate 32 Mhz i,q.
  
•  txSamples:  numsamples:20000
• hghtSamples: start: (20000+30000)/32e6=1562.5 usecs or 234.775 km range.
• compute 1591 heights at 1 usec height step (234km-473 km) range
  
• Set rms in counts at digitizer to about 90 counts on the data. It was higher than this since the rms included the rcvr blanking.
  
• Data file: used  '/share/tdevs0/sasdr.20091025.b0a.00000.pdev -> 00011.pdev .. 12 files.
  

The processing:

• Input 1000 ipps (10 seconds of data).
• for each ipp
  
• for each height of an ipp
• Decode, fourier transform, compute spectral density, and accumulate in height buffer
• Do this for 1000 ipps.
• Compute the median bandpass for all heights.
• Fit a 1591 heights at each ipp, compute power, and accumulate each heights power separately.

• Compute the average bandpass over all heigths to show the bandpass shape.
• To compute the dynamic spectra:
• use 422.5 to 438.5 . This is 8192 data points.
  
• for each height, fit a 1st order polynomial and a 23rd order harmonic to 423 - 437 Mhz.
• divide this height by the fit then subtract 1.
• reduce the image to displayable dimensions:
• from 8192 to 1024 channels using a peak hold on groups of 8 channels.
• average adjacent heights to go from 1591 to 795 heights.
  

• The vertical scale is db above Tsys (defined as the median value 424-436 Mhz).

• The plasmaline gets lost at the peak because of the bandwidth of the ch system.
  

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