10.4 Interferometric Calibration of the Amplitude

For antenna i, the antenna-based amplitude correction is given by (Eq.10.3 and 10.4).

$$a^K_i(t) = T^K_{cali}(t)G^{K}_i(\nu,t)\ensuremath{\mathcal{B}} _i(t)$$ (10.14)

where K = U or L. The decorrelation factor f (see R.Lucas lecture 7) is not taken into account here because it is fundamentally a baseline-based parameter.

In a baseline-based decomposition, the complex gain of baseline ij, ${\ensuremath{\mathcal{G}} _{ij}}$ is given by:

$$\ensuremath{\mathcal{G}} ^K_{ij}(t) = f \times a_i(t) a_j(t) e^{i(\phi_i(t)-\phi_j(t))}$$ (10.15)

and the amplitude of the baseline ij is $\ensuremath{\mathcal{A}} _{ij}$

$$\ensuremath{\mathcal{A}} ^K_{ij}(t) = f \sqrt{T^K_{cali}T^K_{... ... \ensuremath{\mathcal{B}} _i(t)\ensuremath{\mathcal{B}} _j(t)}$$ (10.16)

We will discuss first the term $\ensuremath{\mathcal{B}} _i$ and estimate then the decorrelation factor f, before giving a global scheme of the amplitude calibration.