Dual Polarization Loss

I am starting a new project and would like to use dual circular polarization and transmit using both ports. However before starting, I would like to know how much loss the dual polarization would add to the link budget. Does anyone know a way to calculate that.

You need to make choices before you can weigh the pros and cons.

In which cases do you want to estimate the loss ? Replacing a dipole (or horn or patch array or ?) with a dual polarization antenna (spiral/ sinuous / log periodic toothed or ?)?

Unless you talk specifics, it would not be possible to estimate much.

http://www.phys.hawaii.edu/~anita/ne...k/polariza.pdf
http://www.attplus.cz/hamradio/proje...cle/cppl_b.pdf