US 12,015,380 B2
Radio frequency power amplifier
Daniel Shepphard, Basildon (GB); Stephen Cripps, Basildon (GB); Jeffrey Powell, Basildon (GB); and Roberto Quaglia, Basildon (GB)
Assigned to LEONARDO UK LTD, London (GB)
Appl. No. 17/289,897
Filed by Leonardo UK Ltd, London (GB)
PCT Filed Oct. 31, 2019, PCT No. PCT/EP2019/079858
§ 371(c)(1), (2) Date Apr. 29, 2021,
PCT Pub. No. WO2020/089405, PCT Pub. Date May 7, 2020.
Claims priority of application No. 1817747 (GB), filed on Oct. 31, 2018.
Prior Publication US 2022/0006428 A1, Jan. 6, 2022
Int. Cl. H03F 3/68 (2006.01); H03F 1/02 (2006.01); H03F 1/56 (2006.01); H03F 3/193 (2006.01); H03F 3/60 (2006.01)
CPC H03F 1/0288 (2013.01) [H03F 1/0266 (2013.01); H03F 1/56 (2013.01); H03F 3/193 (2013.01); H03F 3/604 (2013.01); H03F 2200/192 (2013.01); H03F 2200/198 (2013.01); H03F 2200/204 (2013.01); H03F 2200/321 (2013.01); H03F 2200/336 (2013.01); H03F 2200/387 (2013.01); H03F 2200/451 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A radio frequency power amplifier system for amplifying an RF signal, the system comprising:
a balanced amplifier having an input quadrature coupler, an output quadrature coupler, and two amplifiers there-between; the output quadrature coupler having a first output at which the amplified RF signal will be output;
means to modify and/or modulate an impedance at outputs of the two amplifiers, said means including:
a radio frequency control signal source connected to the two amplifiers and configured to provide an RF control signal that will be amplified by the two amplifiers such that an amplified RF control signal will be output at a second output of the output quadrature coupler; and
a signal reflector connected to the second output of the output quadrature coupler and arranged to reflect the amplified RF control signal back to the second output of the output quadrature coupler.