Patent application number | Description | Published |
20110193624 | TUNABLE IMPEDANCE INVERTER FOR DOHERTY AMPLIFIER CIRCUIT - A tunable impedance inverter is presented for a Doherty amplifier circuit having first and second amplifiers connected in parallel between an input circuit for receiving an input signal and an output circuit for supplying an output signal to a load. An impedance inverter is coupled between the first amplifier and the output circuit. The inverter has an input and an output and a tunable mechanical strip line of variable electrical length interposed between the input and the output. An adjuster adjusts the electrical length of the strip line. The adjuster adjustably varies the electrical length of said pathway to thereby adjust the center frequency of said output signal. | 08-11-2011 |
20130076435 | AMPLIFYING SYSTEM - A system for amplifying an input signal can comprise a main amplifier to amplify a delayed version of the input signal. The system can also comprise a peak amplifier to amplify the input signal upon the input signal reaching a threshold level and disable amplification upon the input signal falling below the threshold level. The system can further comprise a voltage combiner to electromagnetically couple the output of the main amplifier and the peak amplifier, such that an output impedance at an output node of the voltage combiner is a high impedance if the input signal is below the threshold level. | 03-28-2013 |
20130093509 | HYBRID COUPLER - A circuit for amplifying an input signal can comprise a plurality of couplers. A splitting coupler of the plurality of couplers can receive the input signal and a combining coupler of the plurality of couplers can provides an output signal. N number of amplifiers can be included in the circuit to amplify the input signal, wherein N is a non-binary integer greater than one. At least one of the plurality of couplers can comprise a hybrid coupler that has two ports terminated into substantially equal reactances. | 04-18-2013 |
20130122834 | BROADBAND AMPLIFIER SYSTEM USING A 3dB QUADRATURE COMBINER TO DYNAMICALLY MODULATE LOAD IMPEDANCE - Systems and methods are provided for modulating a radio frequency (RF) carrier signal with a baseband input signal and amplifying the modulated RF carrier signal to provide an amplified RF signal. A quadrature combiner is configured to provide the amplified RF signal at an associated output port. A main amplifier is configured to receive a first modulated RF signal and provide a main output to one of a through port and a coupled port of the quadrature combiner. An auxiliary amplifier is configured to receive a second modulated RF signal and provide an auxiliary output to an isolation port of the quadrature combiner. | 05-16-2013 |
20130122837 | BROADBAND HIGH EFFICIENCY AMPLIFIER SYSTEM INCORPORATING DYNAMIC MODULATION OF LOAD IMPEDANCE - Systems and methods are provided for producing an amplified radio frequency (RF) signal representing a baseband input signal. A first amplifier amplifies a first intermediate signal to provide a first amplified signal. Second and third amplifiers amplify a second intermediate signal to provide second and third amplified signals. A signal combiner combines the first, second, and third amplified signals to produce the amplified RF signal. An RF modulator modulates an RF carrier signal with a baseband input signal to provide the first and second intermediate signals. The RF modulator provides the first and second intermediate signals such that the first amplified signal is out-of-phase with each of the second and third amplified signals at an output of an active device within the second amplifier when the amplitude of the baseband input signal exceeds a threshold voltage and in phase when the baseband input signal is below a threshold voltage. | 05-16-2013 |
20140198880 | BROADBAND HIGH EFFICIENCY AMPLIFIER SYSTEM - Systems and methods are provided for generating a modulated radio frequency (RF) output signal representing a baseband input signal. A digitizer is configured to sample the baseband input signal and produce an N-bit binary digital signal representing a scaled linear function of the signal amplitude. An RF signal source configured to produce an RF carrier signal. N amplifier paths each include at least one amplifier configured to receive the RF carrier signal as an input and provide a corresponding output RF signal. The amplifiers associated with each of the N amplifier paths are active only when a corresponding bit of the digital signal assumes a first value. A power combiner assembly is configured to combine the outputs of the plurality of amplifier paths to deliver the modulated RF output signal. | 07-17-2014 |
20150303875 | BROADBAND HIGH EFFICIENCY AMPLIFIER SYSTEM AND A METHOD OF CONSTRUCTING HIGH POWER AMPLITUDE MODULATED RF SIGNAL - A broadband high efficiency (RF) radio frequency amplifier architecture is disclosed. Systems and methods are provided for generating an amplified radio frequency (RF) signal representing a baseband input signal. First, second, and third signal paths are configured to amplify first, second, and third intermediate signals to provide respective amplified signals. A signal combiner assembly is configured to combine the amplified signals to produce the compound amplified RF signal. The signals are combined such that a first amplified signal modulates a load impedance at respective outputs of an active device associated with the plurality of amplifiers in the second signal path, and one of the first amplified signal, the second amplified signal, and a sum of the first and second amplified signals modulates a load impedance of an active device associated with the plurality of amplifiers in the third signal path. | 10-22-2015 |