of noise, echo power
from ionogram and 430 coded long pulse
movie of ionograms
The cadi ionosonde was reinstalled in jan2018 (it
had been sent to cadi to get repaired).
- The control software runs on the cadi cpu (under linux).
- The users are root and cadi
- A vnc session is available for login.
- warning (the vnc session currently belongs to root since it
is started in the rc.local without su )
- the ionosonde is normally run every 15 minutes via a root
- programs on cadi cpu:
- /usr/sbin/cadi configfile.dat
- runs the ionsonde, gathers the data, and writes to output
- this is what the crontab runs every 15 minutes
- data is written to /var/cadidata
- See the data file format:
- /usr/sbin/cadidisplay -f filename
- will read the .MDL file and plot the ionogram.
- there are some scripts under /home/cadi that have been used
to copy data from the cadi cpu to other computers on aonet,.
- Data locations;
- the .MDL files are written to /var/cadidata/xxx.MDL
- eventually it gets moved to /home/cadi/data/yyyy
- historically data has been copied to
- Offline software
- idl routines (under cadi) that let you read in the .mdl
files and generate an ionogram.
180130: initial cadi tests
The cadi was run 30jan18 through 01Feb18
(together with a world day).
- The data from the cadi host was copied to
- the monnamtonum.sc script was run to change the month names to
numbers (so the file order is now date order).
- the idl routine: /share/megs/phil/x101/cadi/ldcadifiles.pro
was run to load all of the data files into
- hdrAll[n]: 1 header per datafile
- frqAll[300,n]: freq channel info for the 300 freq channels
of each file
- had freq, avg noise power (averaged over heights),
gainflag, thresholding flag, numbers of heights/dopper
channels recorded, a pointer in eAll[m] for start of this
- eAll[m] : this holds the echo data recorded by the cadi
- Only height,doppler channels above a specified threshold
- this contains:
- ifreq - first index into frqall[300,n] for this entry
- ih - height index for this
- for our config, heights go 90km, to 510 km in 3km
- so ih =0 is 90km ih=1 is 93km...
- dopBin- doppler bin for this entry.
- our cadi processing takes 8 ipps (25 ms each) at a
- removes the 13 length barker code on the received
- then does an 8 point fft on each height
- the dopbin is 0..7 , the doppler freq bin for this
- iq: iq voltage for this entry. units are a/d counts
- this is probably after the 8 point fft.
The plots show the
recorded voltages and powers for the 3 days. (.ps) (.pdf):
- Page 1: echo voltages:
- Top: i/q voltages for recorded echo power (for the 3
- Black is the I digitizer , red is the Q digitizer
- These are 8 bit digitizers (-128 to +127)
- The echo data is only recorded if it is above a preset
- The I digitizer has a 9 level DC offset. The Q digitizer
has a 1 level DC offset
- Bottom: histograms of the i,q data
- black is digitizer I, red is digitizer Q.
- Page 2: noise and echo power.
- Black: the average noise power for an ionogram vs hour from
- I integrated over all heights and frequencies.
- Red: the power from the echo returns that were recorded.
- Page 3: over plot average noise power (over hghts) vs freq for
- an offset has been added to each spectra for display
- there is an rfi spike visible at 2.3 Mhz.
Dynamic spectra of the
average noise power vs time (.gif)
- For each frequency channel, the noise power is averaged
over all heights (giving a 300 channel spectra for each
- I limited the x axis to 1 to 10 MHz.
- the tick marks in the middle are not correctly spaced
since the freq spacing is not linear (someday I'll fix the
image plotting routine that asks for the min, max value!). The
constant vertical lines is actually at 2.36 MHz.
- The white strips horizontal stripes (at 10-15 hrs) and 34-37
hours are when we got good ionograms.
Compare fof2 from ionogram and
Data taken 20180120, 11:45 ast is shown
for the ionosonde, and for the clp data taken with the echotek
of the ionograms for the 3 days (.avi) (.mov)
- I made ionograms from each of the 285 .mdl files
- data was input with cadi_inpfile
- the ionograms was created with cadi_doimg
- jpegs for each ionogram were written with mkkpeg
- the movie was then made with mkmov.sc
- all in x101/cadi/
- Not many of the ionograms are usable.
- the better ionograms correspond to when the average noise
power was lower (see above).
- the cadi was run for about 3 days.
- fof2 freq for 11:45 30feb18 had cadI; 5.95, clpData:6.07. the
430 data was about 75Khz higher.
- there is a 9 a/d level offset in the I digitizer
- most ionograms were not usable
- there were 2 periods (of about 4 hours) when we had good
- there is probably something not working correctly
We have old documentation that describes running
cadi under windows.