Azimuth swings were done with the cband receiver on 28aug12.

The setup was:

- az 270-630 and back at +/- .4deg/sec
- clear sky, data taken around 11am.

- dome at za=15deg
- mock spectrometer with 7 boxes covered 5 to 6 GHz
- 172MHz bw, 8192 channels per box
- .1 sec sampling (averaged to 1 second)

- input the data averaging to 1 second
- interpolate az positions to center of data records.
- Create bandpass correction
- compute total power of each spectra.
- compute median of spectra that belong to the lowest 20% of the tp above.
- fit a linear polynomial and 35th order harmonic to the median bandpass. use this as the bandpass correction.
- divide each 1 second spectra by the bandpass correction
- compute the median of each 1 sec spectra and remove it (this is to get rid of continuum sources).

CW swing |
CCW swing |

5074MHz | 5074MHz |

5224MHz | 5224MHz |

5374MHz | 5374MHz |

5524MHz | 5524MHz |

5674MHz | 5674MHz |

5824MHz | 5824MHz |

5974MHz | 5974MHz |

- Artifacts:
- Each bandpass is divided by a fit rather than a median
bandpass. This is so we don't cancel out constant
birdies (that may be coming from inside the dome). Because of
this, some artifacts remain in the image.

- the sinx/x birdie at the center of each band is probably from the mock spectrometer
- The ripples at the edge of the band is from fitting the bandpass
- completely dark stripes.
- The bandpass fitting routine throws out outliers. For
really large rfi, they points are thrown out, so the fit is
not constrained at these points (they should be set to some
peak value). Depending on the fit, these values may be
negative or positive.

Birdies were identified by looking at the
dynamic spectra. The avg power over the birdie bandwidth was
computed and then plotted vs azimuth. The clockwise and counter
clockwise swings were over plotted to see if the birdies repeated
in azimuth (for this to happen then need to be stable in time).

(Coming soon)

processing: x101/120828/cb_azswing/doall.pro

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