Systems and Methods of RF Power Transmission, Modulation and Amplification

Abstract

Methods and systems for vector combining power amplification are disclosed herein. In one embodiment, a plurality of signals are individually amplified, then summed to form a desired time-varying complex envelope signal. Phase and/or frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time-varying complex envelope signal. In another embodiment, a time-varying complex envelope signal is decomposed into a plurality of constant envelope constituent signals. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. Embodiments also perform frequency up-conversion.

What is claimed is: 
     
         1 . A method of controlling an amplifier, comprising:
 determining a power level of an output waveform;   determining a desired amplifier class of operation according to the determined power level; and   controlling the amplifier to operate according to the desired class of operation.   
     
     
         2 . The method of  claim 1 , wherein determining a power level comprises determining an instantaneous power level as a function of a desired output waveform envelope. 
     
     
         3 . The method of  claim 1 , further comprising controlling the power amplifier to operate according to a new class of operation. 
     
     
         4 . The method of  claim 3 , wherein controlling the power amplifier to operate according to a new class of operation comprises transitioning the power amplifier through an intermediary class. 
     
     
         5 . The method of  claim 1 , further comprising:
 determining the instantaneous power level of the desired output waveform; and   controlling the power amplifier to operate in according to a new class of operation based on the instantaneous power level.   
     
     
         6 . The method of  claim 1 , further comprising:
 determining an average output power of the desired output waveform; and   controlling the power amplifier to operate according to a new class of operation based on the average output power.   
     
     
         7 . The method of  claim 1 , further comprising:
 determining the instantaneous power level of the desired output waveform   determining an average output power of the desired output waveform; and   controlling the power amplifier to operate according to a new class of operation based on the instantaneous power level and average output power.   
     
     
         8 . The method of  claim 1 , wherein controlling the power amplifier comprises controlling a drive level and a bias of the amplifier so that an output current conduction angle reaches a predetermined level based on the desired class of operation. 
     
     
         9 . The method of  claim 1 , wherein controlling the amplifier comprise generating a pulse width modulated output signal. 
     
     
         10 . The method of  claim 1 , wherein controlling the amplifier comprises operating the amplifier in a switch mode. 
     
     
         11 . An apparatus, comprising:
 an amplifier; and   an amplifier controller configured to:
 determine a power level of an output waveform; 
 determine a desired amplifier class of operation according to the determined power level; and 
 control the amplifier to operate according to the desired class of operation. 
   
     
     
         12 . The apparatus of  claim 11 , wherein the amplifier controller is configured to determine a power level by determining an instantaneous power level as a function of a desired output waveform envelope. 
     
     
         13 . The apparatus of  claim 11 , wherein the amplifier controller is further configured to control the power amplifier to operate according to a new class of operation. 
     
     
         14 . The apparatus of  claim 13 , wherein the amplifier controller is configured to control the power amplifier to operate according to a new class of operation comprises transitioning the power amplifier through an intermediary class. 
     
     
         15 . The apparatus of  claim 11 , wherein the amplifier controller is further configured to:
 determine the instantaneous power level of the desired output waveform; and   control the power amplifier to operate in according to a new class of operation based on the instantaneous power level.   
     
     
         16 . The apparatus of  claim 11 , wherein the amplifier controller is further configured to:
 determine an average output power of the desired output waveform; and   control the power amplifier to operate according to a new class of operation based on the average output power.   
     
     
         17 . The apparatus of  claim 11 , wherein the amplifier controller is further configured to:
 determining the instantaneous power level of the desired output waveform   determining an average output power of the desired output waveform; and   controlling the power amplifier to operate according to a new class of operation based on the instantaneous power level and average output power.   
     
     
         18 . The apparatus of  claim 11 , wherein the amplifier controller is configured to control the power amplifier by controlling a drive level and a bias of the amplifier so that an output current conduction angle reaches a predetermined level based on the desired class of operation. 
     
     
         19 . The apparatus of  claim 11 , wherein the amplifier controller is configured to control the amplifier by generating a pulse width modulated output signal. 
     
     
         20 . The apparatus of  claim 11 , wherein the amplifier controller is configured to control the amplifier by operating the amplifier in a switch mode.