Patent ID: 8384475
Filing Date: 2013-02-26
Classification: H03F,H03H,H04B

Abstract:
1. A composite amplifier for use in a radio terminal of a telecommunications wireless system, comprising: at least two power amplifiers that are arranged to be connected to an output combiner network and to a load, the output combiner network comprising at least one dynamically tunable reactance; wherein said at least two power amplifiers are configured to be differently driven; wherein at least one of the impedances seen by each of said at least two power amplifiers is arranged to be dynamically tuned via tuning of the at least one dynamically tunable reactance such that the instantaneous efficiency of the composite amplifier is increased; and wherein said at least one of the impedances seen by each of said at least two differently driven power amplifiers appears to at least one of the two differently driven power amplifiers as a resistance that is substantially inversely proportional to the square of the output signal amplitude's envelope of said composite amplifier.