Patent ID: 7173977

Claim:
A method of transmitting a layered modulation signal having a first signal layer having first signal symbols and a second signal layer having second signal symbols, comprising the steps of: determining a first signal layer modulation carrier power C L at least in part according to a first signal layer clear sky margin M L and a first signal layer availability; determining an second signal layer modulation carrier power C U at least in part according to an second signal layer clear sky margin M U and an second signal layer availability; modulating the first signal symbols according to a first carrier at the determined first signal layer modulation carrier power; modulating the second signal symbols according to a second carrier at the determined second signal layer modulation carrier power to generate the layered modulation signal; transmitting the modulated first signal symbols and second signal symbols; and wherein the second signal layer clear sky margin is less than the first signal layer clear sky margin when the first signal layer availability and the second signal layer availability are substantially equal.