The setup:

• gregorian dome 430 txmitter/receiver with 420-442 filter installed on receive.
  
• cycle thru coded long pulse, power, and mracf
• codedlong pulse: 40 seconds (2 usec baud)
• mracf, power 10 seconds each
• 10 millisecond ipps were used.
  
• Rdev setup:
• 160 Mhz clock, decimate by 5: 32 Mhz Bw, 16 bits output, data  rate 32 Mhz i,q.
  
•  txSamples: skip 2, numsamples:20000
• hghtSamples: start: 20000/32e6=625 usecs=93km: numSamples:65000
• Set rms in counts at digitizer to about 80 counts.
• Data file: used  '/share/tdevs0/sasdr_gold.20090924.b0a.02300.pdev'

The transmitter samples:

• Page 1: When the programs cycled:
• Top: the power in the Tx sample 2000: (62.5 usecs).
• This is beyond the end of the barker code
• You can see the program transitions because the power changes a little between program types
• There is only 5 secs/20 seconds of data for pwr,mracf / clp. There should be 10/40 so we are missing 1/2 of the data.
• Bottom: The Voltage in the I digitizer for sample 2000.
  
• Page 2:  Examples of clp, mrac, power tx samples:
• 75 usecs of tx samples was plotted for the 3 programs. I chose an ipp where the i,q digitizers had equal power.
• There is a .5 usec oscillation apparent in the data.
• Page 3: ipp to ipp oscillations in the transmitted power:
• The power was varying between the I and Q samples on an ipp to ipp basis. To measure this i computed:
• y[i]=mean(txSmp[0:1600,i]^2) and then plotted this versus ipp.
• The power variation is seen in all 3 programs.
• The frequency is doubled since i squared the voltage.
• Page 4: Spectrum of the ipp to ipp tx oscillations.
• These plots show the spectrum of the ipp to ipp oscillations.
  
• In power it is: 5.86 Hz. In voltage it is 2.93 Hz.
• Page 5: Coded long pulse Average transmitted spectrum:
• 3000 points (93.5usecs) from the start of each clp ipp was used to compute the spectrum.
• The spectra were then averaged over 19 seconds of data.
• Top: 32 Mhz bandwith of average spectra.
• I've flagged 2Mhz where the previous oscillation within the ipp was seen.
• Bottom: blowup +/- 1 Mhz about 430.
• The nulls are at the correction locations (.5 Mhz) for a 2 usec baud).
• The main lobe is offset by about 100 Khz.

The data samples:

• 1 second of data was used (100 ipps).
• Page 1:Average all heights together (linear scale)
  
• Top: No decoding
• Bottom: with decoding.
  
• Page 2:Average all heights together (db scale)
• Top: No decoding
• Bottom: with decoding.
• Page 3:Average spectra 1 height (123 km) (db scale)
• Top: No decoding
• Bottom: with decoding.
• The decoding is not working.
• I tried decoding a single height using the tx sample offset by up to +/- 20 ipps from the correct ipp. I did not see any narrowing of the ion line or the plasma line.
  

• The x axis is frequency, the y axis is range.
• Images were made with and with decoding.
• The images were flattened using the upper 15 km of data.  
  

Conclusions:

• We are only getting 1/2 of the data output
• the clp data does not decode even after shifting up/down by up to 20 ipps.
• There is an ipp to ipp oscilation of about .34 hz.
• With an ipp there is a 2 Mhz oscillation (30 db down).
• The main lobe of the clp tx spectrum is offset by about 100 Khz but the nulls are in the correct location.
  

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