An apparatus and a method for an Envelope Elimination and Restoration
(EER) power transmitter are provided. The apparatus includes a signal
separator for splitting a transmit signal to an amplitude component and a
phase component, an orthogonal modulator for modulating the phase
component into a Radio Frequency (RF) signal, a bias modulator for
linearly amplifying the amplitude component, for determining a bias
voltage according to a magnitude of the amplitude component, and for
providing a current generated using the determined bias voltage to a
high-efficiency power amplifier and the high-efficiency power amplifier
for amplifying the RF signal using the linearly amplified amplitude
component as a drain bias voltage and using the generated current as a
drain bias current.