uv coverage
Using a Cartesian coordinate system (X,Y,Z) with
Z towards the pole, X towards the meridian, and Y towards East, the
conversion matrix to u,v,w is
Eliminating h from Eq.2.46 gives the equation of an ellipse:
The uv coverage is an ensemble of such ellipses. The choice of antenna configurations is made to cover the uv plane as much as possible.
Baseline measurement
Assume there is a small baseline error,
(
). The phase error is
From the shape of Eq.2.49, one can see that the
determination of
requires large variations in
h, preferably at declination
, while that of requires large variations in . However, in
Eq.2.50 is multi-valued (the ambiguity...). Hence,
the system to solve is in fact