I spotted this discussion midway.
Here are a few thought on the matter from an Amateur Radio operator
perspective.
Depending on the frequencies in question you can use several COTS
amplifiers
for specific bands needed, and use a Diplexer/Triplex/Quad… (basically
filters to separate the bands.) at the inputs, and outputs on the amps
needed for your application.
a few COTS examples I found with Google,
Ham Radio Outlet Product Details - Item Not found,
Ham Radio Outlet Product Details - Item Not found I have no connection
with
HRO other then being happy with the stuff I bought from them in the
past.
Please let me know if the suggestion was of use.
Justin N2TOH