Abstract: The apparatus includes an amplifier (204) having an input and an output, the amplifier output coupled to an input of a Doherty amplifier (208). The Doherty amplifier (208) includes a control input and a Doherty output. The apparatus further includes a detector (224) having an input coupled to the output of the Doherty amplifier (208). The detector provides a detected signal at its output, to a controller (228), the controller responding to the detected signal by producing a first (230) and second control output (231). The first control output is coupled to a switching regulator (232) input, the switching regulator having an output coupled to the control input of the Doherty amplifier. The second control output is coupled to a control input of a variable attenuator (202), the output of the variable attenuator coupled to the input of the amplifier (204).

Abstract: A method and apparatus in a feedforward amplifier (100) includes a summer (293) summing the desired signal (12) with a pair of tag signals (241, 242). An error signal (226) is coupled with a delayed version of the summed signal (48). The phase and amplitude of signals (226, 237) are adjusted according to a first and second gradient decent controllers (221, 231) output signal (225) which is based on the first DC signal (224) and output signal (235). The output signal (235) is based on the detected power level of a leaked signal at the output coupler (62). The adjustment of the input signal (237) to the second amplifier, when the detected power level fluctuation exceeds a predetermined threshold level, is repeated. The tag signals (241) are produced in phase lock with the sweeping detecting (222) function.

Abstract: An apparatus (10) for adjusting peak-to-average power of a multicarrier signal. The apparatus (10) comprises a first (26) and second (28) combiner, a phase-changing device (30), and a switch (36). The first combiner (26) receives a first group of channels (20) and a second group of channels (22) and produces a first combined signal (46). The phase-changing device (30) receives the first group of channels (20) and produces a group of phase-adjusted channels. The second combiner (28) receives the phase-adjusted channels and the second group of channels (22) and produces a second combined signal (48), and the switch (36) responds to the first (26) and second (28) combiners and selects at least one of the first (46) and second (48) combined signals.