  A method for increasing efficiency of radio frequency (RF) amplifier
employing laterally diffused metal oxide semiconductor (LDMOS) transistors
coupled to an RF exciter depending on the emission mode of modulated RF input
signals generated by exciter, if exciter output signal is of a type where
modulated RF signals do not have continuously varying envelope, biasing the
LDMOS transistor in the RF amplifier with fixed quiescent drain current and
fixed drain voltage supply to cause LDMOS transistors to operate in compression
and if exciter output signal is of a type where modulated RF signals do have
continuously varying envelope, biasing the LDMOS transistors in the RF
amplifier for linear operation.
