Very interesting posts and useful.
I'm also trying to make a link budget for a project of similar characteristics.
I was wondering which kind of antenna (model?) are you planning to use to have a Gar/Tsys of -15.94 ?
In most of antennas specs, the manufacturers usually only give the gain (Gar), and calculating the System noise temperature is pretty confusing (Tsys). I've seen many formulas and long technical explanations to calculate it.
But is there any simple way to calculate it? and have a good approximation for a first draft of a Link budget ?