Prior to the
visitor center power
shutdown, we transmitted a birdie from the visition center platform
to find the azmiuth position for the peak recieved signal.
The setup:
- Dome set to 19 deg za.
- lbw reciever in linear mode, cfr 1403 Mhz
- 1403.2 Mhz signal generated with agilent 3Ghz synthesizer.
- Interim correlator recorded 1024 channels, 1.5 Khz resolution, 9
level sampling, 1 second dumps.
- The probe used to xmit was :
- ETS LINDGREN 7405-904B Efield 3.6 cm ball with upper
resonance > 1 GHz.
- The probe was positioned at:
- east edge of platform:
- az moved 359 to 400 degs
- -25dbm transmitted
- center of platform
- az moved 359 to 400 degs
- -40 dbm transmitted
- west edge of platform:
- az moved 350 to 390 degs
- -40 dbm transmitted
- return to center of platform.
- az moved 350 to 390 degs
- -40 dbm transmitted.
Processing, plotting the data:
- The median was removed from each 1 second spectra
- The peak value within 10 Khz of 1402.3 was used as the peak
received value.
- The azimuth position for each 1 second was interpolated to the
center of the data sample.
- The CW and CCW swings were overplotted.
The plots show
the peak signal
vs azimuth for the 4 tests (.ps) (
.pdf):
Summary:
- The dome was at 19 deg za.
- The CW and CCW swings repeated the same pattern.
- The structure in the pattern is probably from the length of the
scattering elements (beams) and the wavelength.
- The azimuth peaks were:
- East edge of platform: az=380.13
- Center of platform: az=364.65,
364.90
- These two measurements were separated by about 20 minutes
- the probe was moved to the west position and then returned to
the center for the final measurement.
- East edge of platform: az=354.87
- For
the visitor center power shutdown, the azimuth was positioned to 364.82
deg.
processing:x101/111101/azpos.pro