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SOLVE SKYDIP

Skydips are special scans where the antenna is moved in elevation at a fixed azimuth. For each elevation (regularly spaced in airmass), total power from the sky, $ P_{sky}$ , and the hot load, $ P_{hot}$ , are recorded. Since one knows the effective temperature of the hot load, $ T_{hot}$ , one can derive either the receiver temperature, $ T_{rec}$ , or the forward efficiency ,$ \eta_f$ , via:

$\displaystyle (T_{hot}+T_{rec})\times \frac{P_{sky}}{P_{hot}} - T_{rec} = \eta_f \times Airmass \times \tau_{zenith} + (1-\eta_f)\times T_{ground}$ (22)



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