Oblon, Spivak, McClelland, Maier & Neustadt, P.C.
Multi-band feed-forward amplifier and adjustment method therefor
A multi-band feed-forward amplifier is formed by: a dividing part for dividing and applying an input signal containing signals of multiple frequency bands to a linear signal path and N vector adjustment paths of a distortion detecting circuit; frequency band signal extractors provided in the N vector adjustment paths, respectively, for extracting signals of N frequency bands; N vector adjusters for adjusting the vectors of the output signals from the respective frequency band signal extractors; a main amplifier for amplifying the output signals from the N vector adjusters; a combining/dividing part for combining the amplified signals and the signal from the linear signal path of the distortion detecting circuit and for dividing and applying the combined output to a linear signal path and N distortion injection paths of a distortion cancelling circuit; frequency band signal extractors provided in the N distortion injection paths, respectively, for extracting the signals of the N frequency bands; vector adjusters for adjusting the vectors of signals separated into the N frequency bands; an auxiliary amplifying part for amplifying the vector-adjusted N signals; and a combining part for combining the amplified signals and the signal from the linear signal path of the distortion cancelling circuit.
NTT DoCoMo, Inc.
H
H03F
inventional
Yasunori Shoichi
Suzuki Narahashi