Convert radiation pattern from u/v form to azimuth/elevation form

`pat_azel = uv2azelpat(pat_uv,u,v)`

`pat_azel = uv2azelpat(pat_uv,u,v,az,el)`

```
[pat_azel,az_pat,el_pat]
= uv2azelpat(___)
```

expresses
the antenna radiation pattern `pat_azel`

= uv2azelpat(`pat_uv`

,`u`

,`v`

)`pat_azel`

in azimuth/elevation
angle coordinates instead of u/v space coordinates. `pat_uv`

samples
the pattern at *u* angles in `u`

and *v* angles
in `v`

. The `pat_azel`

matrix
uses a default grid that covers azimuth values from –90 to
90 degrees and elevation values from –90 to 90 degrees. In
this grid, `pat_azel`

is uniformly sampled with
a step size of 1 for azimuth and elevation. The function interpolates
to estimate the response of the antenna at a given direction.