Aperture in ssap

[Carlos Rodrigo]

Hi

I am trying to implement a SSAP service and make it as compliant as possible.

But I see that the Char.SpatialAxis.Coverage.Bounds.Extent (Aperture) is mandatory
and it is expected to contain a "double" value.

But I have no idea of the aperture used for the observations. In some cases the spectra do not come
from an observation. They are theoretical or a combination of observations of whatever.

I don't intend to discuss now why this is mandatory. Just how I can implement a SSA service
including a mandatory field which value I cannot fill.

I wonder which of this would be better:

<PARAM name="aperture" utype="Char.SpatialAxis.Coverage.Bounds.Extent" datatype="char" arraysize="*"
value="">

<PARAM name="aperture" utype="Char.SpatialAxis.Coverage.Bounds.Extent" datatype="double"  value="0">

<PARAM name="aperture" utype="Char.SpatialAxis.Coverage.Bounds.Extent" datatype="double"  value="null">

any other idea?

I would appreciate any help

Thanks

Carlos