Physics#

The calibration engine implements the standard heterodyne calibration equation, converting raw detector counts into antenna temperature \(T_A^*\) corrected for atmospheric absorption. This section derives each component of the equation and maps it to its implementation.

Symbol Reference#

Symbol

Meaning

Unit

Typical range

\(T_A^*\)

Antenna temperature (atmosphere-corrected)

K

−1 to 100

\(\gamma\)

Gain calibration factor (counts → K)

K/count

10⁻⁴ to 10⁻²

\(T_{rec}\)

Receiver noise temperature (SSB)

K

100 to 5000

\(T_{sys}\)

System temperature

K

200 to 10000

\(\tau_0\)

Zenith optical depth

Np

0.01 to 5

\(t_r\)

Atmospheric transmission

0.01 to 0.99

PWV

Precipitable water vapour

mm

0.01 to 10

\(f_{eff}\)

Forward efficiency

0.95 to 0.99

\(g_s x_s\)

Signal sideband gain × suppression

0.5

\(g_i x_i\)

Image sideband gain × suppression

0.5