scispace - formally typeset
Patent

Multi-mode amplifier system

Reads0
Chats0
TLDR
In this article, an amplifier system switches between modes of operation based upon a characteristic of an input signal relative to a first threshold level and a second threshold level, and a mode selector selects the operation mode by transmitting an amplitude modulated signal plus a variable headroom voltage to a supply terminal of a power amplifier during the envelope tracking mode, an amplitude and phase modulated input signal during the polar mode and a substantially constant amplitude signal to the supply terminal during the linear mode.
Abstract
An amplifier system is provided that switches between a linear mode of operation, an envelope tracking mode of operation and a polar mode of operation. The amplifier system switches between modes of operation based upon a characteristic of an input signal relative to a first threshold level and a second threshold level. A mode selector selects the operation mode by transmitting an amplitude modulated signal plus a variable headroom voltage to a supply terminal of a power amplifier during the envelope tracking mode, an amplitude modulated signal to the supply terminal and phase modulated input signal during the polar mode and a substantially constant amplitude signal to the supply terminal during the linear mode.

read more

Citations
More filters
Patent

Pseudo-envelope following power management system

TL;DR: In this article, a pseudo-envelope follower power management system was used to manage the power delivered to a linear RF power amplifier, which is used to control a linear power amplifier.
Patent

Power loop control based envelope tracking

TL;DR: In this article, the transceiver circuitry regulates a modulated power supply voltage, which is used by the radio frequency power amplifier to provide power for amplification, based on the difference between the target output power from the RFP amplifier and the measured output power of the RF power amplifier.
Patent

PA envelope power supply undershoot compensation

TL;DR: In this article, a step change from a high magnitude to a low magnitude that exceeds the step change limit is considered, which may cause the PA envelope power supply to undershoot.
Patent

Power management system for multi-carriers transmitter

TL;DR: In this article, a power management system for a multi-carrier transmitter is described, which includes a first switcher having a control input and a power output, and a second switcher with a controller input and power output.
Patent

Optimization methods for amplifier with variable supply power

TL;DR: In this paper, a switch can be controlled to include or exclude a feedback network in a feedback path to the amplifier to adjust a response of the amplifier dependent on a region of operation (e.g. linear region or compression region).
References
More filters
Journal ArticleDOI

High-efficiency power amplifier using dynamic power-supply voltage for CDMA applications

TL;DR: In this article, a boost DC-DC converter with an operating frequency of 10 MHz is demonstrated using GaAs heterojunction bipolar transistors, and an envelope detector circuit with a fast feedback loop regulator is discussed.
Patent

Method and apparatus for operating a radio-frequency power amplifier as a variable-class linear amplifier

TL;DR: In this paper, a variable-class linear amplifier (600, 800, 900) applies a supply type of envelope modulation to an RF power amplifier operating in or near compression at highest envelope amplitudes, and transitions gradually to an envelope tracking type of operation at intermediate amplifier amplitudes.
Patent

Method and apparatus for generating a linearly modulated signal using polar modulation

TL;DR: In this article, an apparatus and method for generating a linearly modulated signal in a polar modulation system is described, where a signal for transmission is separated into a phase component and an amplitude component, and a carrier signal is modulated with the phase component in a phase modulator, creating a phase distortion.
Patent

RF transmitter with extended efficient power control range

TL;DR: A highly efficient radio frequency (RF) transmitter provides both wide bandwidth and an extended power control range as mentioned in this paper, which is useful in wireless communications to increase both handset talk time and battery life.
Patent

Method, device, phone and base station for providing envelope-following for variable envelope radio frequency signals

TL;DR: In this paper, an envelope-following unit is used to output a supply voltage in accordance with a variable envelope of an input baseband signal, wherein using the efficient envelope following unit includes: 1) using a bandwidth-limiting mapping unit to determine a reference signal based on the base band signal; and 2) using an envelope tracking power converter to output the supply voltage, responsive to the reference signal, to the linear RF power amplifier.