Sensitivity single dipole


Tsys using sky and absorber
Sensitivity using crosses from dipole 1.

    The sensitivity of the byu system was measured using a single dipole fed down to the AO iflo system and recorded on the interim correlator. Crosses on continuum sources as well as temperature measurements using sky and absorber.

Tsys using sky and absorber:

    On 26aug10 Tsys was measured using sky and absorber. The setup was:

Processing the data:

Analyzing the data:

    The plot shows the Hot,cold measurement (.ps) (.pdf):

    These measurements used a single dipole. The phased array feed will have different values.

processing: x101/100831/

Sensitivity measurements using crosses on dipole 1.

    Crosses were done on continuum sources using dipole 1

The cross setup was:

Processing the data

The first plots show the strip data with the fits overplotted for 7 crosses done on A0..A6 (.ps) (.pdf)
The next set of plots   show the results of all the fits (.ps) (.pdf):
processing: x101/projects/byuPhAr/idl/cross/, x101/projects/byuPhAr/test/spillover,


Tspillover +  Tsky
Dipole1:53k, dipole2:60k
Assumes Trcv =45K
100 K
Assumes Trcv=45k
11 Jy
Only relies on the source flux (and the 2d fit).
251  m^2/K
just  2760/SEFD
Ae from Ae/Tsys and Tsys
25100 m^2
assumes Trcv=45K, Tsys=100K
  • This will increase as Tsys goes up
  • the geometric area is from german's "last ray) over the tertiary .
Beam widths
  • major axis: 150 asecs
  • minor axis: 170 asecs
  • avg:            160 asecs
  • The avg bw is smaller than the lbw receiver at 1610 MHz: 178 asecs
taper at tertiary edge
  • dipole:6 db
  • horns:15-17db
  • Using 1/2 lambda dipole lambda/4 above ground plane from kraus.
  • this compares with the 15-17 db tertiary edge taper for the single pixel horns
  • The smaller edge tape should give a narrower beam width for the dipole.

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