High Efficiency Amplification
AssigneeNujira Limited
InventorMartin Paul Wilson
Life of this patent
Estimating the term…
Abstract
A radio frequency amplification stage comprising: an amplifier for receiving an input signal to be amplified and a power supply voltage; and a power supply voltage stage for supplying said power supply voltage, comprising: means for providing a reference signal representing the envelope of the input signal; means for selecting one of a plurality of supply voltage levels in dependence on the reference signal; and means for generating an adjusted selected power supply voltage, comprising an ac amplifier for amplifying a difference between the reference signal and one of the selected supply voltage level or the adjusted selected supply voltage level, and a summer for summing the amplified difference with the selected supply voltage to thereby generate the adjusted supply voltage.
Claims10
An apparatus comprising:
- a controller arranged to receive a digital envelope signal, the baseband controller comprising:
- a digital-to-analog converter for converting the digital envelope signal into an analog envelope signal;
- and
- a digital controller for generating a digital control signal for a switching stage in dependence on the digital envelope signal,
- a modulated supply stage comprising:
- a switching stage for receiving the digital control signal and for selecting one of a plurality of supply voltages in dependence on the digital control signal;
- a combiner for combining the selected supply voltage with an error signal, and for providing a power supply signal;
- and
- an error amplifier for receiving the analog input signal and the output of the combiner and for generating the error signal;
- an analog interface for connecting the analog input signal from the controller to the modulated stage;
- and
- a digital interface for connecting the digital control signal from the controller to the modulated supply stage.
A method of controlling an amplification stage including an amplifier and an envelope tracking power supply for the amplifier, comprising:
- receiving a digital envelope signal;
- converting the digital envelope signal into an analog envelope signal;
- providing the analog envelope signal on an analog interface;
- generating a digital control signal in dependence on the digital envelope signal;
- providing the digital control signal to a power supply switching stage on a digital interface;
- connecting one of a plurality of power supply voltages to an output of the switching stage in dependence on the digital control signal;
- combining the connected power supply voltage and an error signal to generate the supply voltage for the amplifier;
- and
- amplifying the difference between the supply voltage for the amplifier and the analog envelope signal to generate the error signal.
Dependencies are inferred from the claim text.