Method and apparatus for linearizing an efficient class D/E power amplifier using delta modulation
AssigneeHewlett-Packard Company
InventorDavid Su
Life of this patent
Estimating the term…
Abstract
A delta-modulated magnitude amplifier is used to amplify the magnitude component of an RF power amplifier that employs envelope elimination and restoration. The delta-modulated amplifier introduces a smaller amount of non-linearity than traditional approaches, which are based upon pulse-width modulation. The disclosed technique can be implemented using switched-capacitor circuits in a standard MOS technology with only two external components, i.e., an inductor and a capacitor. Thus, the disclosed technique allows the implementation of an efficient and yet linear RF power amplifier using low-cost MOS technology.
Claims20
A linear power amplifier, comprising:
- a magnitude amplification path for a magnitude component of an input signal;
- a delta-modulated magnitude amplifier within said amplification path;
- and
- a phase amplification path for a phase component of said input signal, said phase component amplification path being coupled to said magnitude amplification path to receive an amplified magnitude component from said delta-modulated magnitude amplifier and, responsive to said amplified magnitude component and said phase component, generating an output signal that linearly relates in phase and amplitude to said input signal.
An efficient, highly linear RF power amplifier, comprising:
- a phase output stage that amplifies a phase component of an RF input signal to generate an RF output signal;
- and
- a delta-modulated magnitude amplifier connected as power supply for said phase output stage, said delta-modulated magnitude amplifier amplifying a magnitude component of said RF input signal by delta modulation to generate an amplified magnitude signal, said amplified magnitude signal amplitude modulating said RF output signal.
A method for efficient, highly linear RF power amplification, the method comprising steps of:
- amplifying, using delta modulation, a magnitude component of an RF input signal to generate an amplified magnitude signal;
- amplifying a phase component of said RF input signal to generate a phase-modulated RF output signal;
- and
- amplitude modulating said phase-modulated RF output signal using said amplified magnitude output signal to produce an amplitude- and phase-modulated RF output signal.
Dependencies are inferred from the claim text.