Multi-Mode Power Amplifier Chains for Low-Power Efficiency

Solution Overview

Problem

Power amplifiers in wireless communication systems face inefficiency at lower output power levels due to high bias current and voltage, leading to significant battery power consumption in portable terminals, which shortens standby and talk times.

Innovation Solution

The development of efficient multi-mode linear power amplifiers that support multiple radio technologies and frequency bands, utilizing multiple chains in parallel with adjustable bias current and transistor sizes, and incorporating pre-distortion for non-linear compensation, to meet spectral mask requirements across varying output power levels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If power amplifiers are designed with large-size transistors and high bias current and voltage to meet spectral mask requirements at maximum output power, then spectral mask compliance is improved, but efficiency deteriorates at lower output power levels

Engineering Contradiction:

Improvespectral mask complianceVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The power amplifier is divided into multiple parallel chains (first linear power amplifier and second linear power amplifier), each capable of operating independently or in combination. This segmentation allows the system to use only the necessary amplification capacity for current operating conditions, avoiding the energy waste of running a single large amplifier at low power levels.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically switches between different operating modes: single-chain mode for low to medium power levels and dual-chain mode for maximum power levels. This dynamic reconfiguration optimizes efficiency by matching the amplification resources to the actual power requirements, preventing unnecessary energy consumption at lower output levels.

Inventive Principle:

Principle #15Dynamics

2Power

If high bias current and voltage are used to meet spectral mask requirements, then output power capability is improved, but efficiency at lower output power levels deteriorates

Engineering Contradiction:

Improvemaximum output powerVSAvoidpower consumption

Core Design Contradiction:

PowerVSLoss of energy

Solution Approach 1:

The power amplifier is divided into multiple parallel chains (first linear power amplifier and second linear power amplifier), each capable of operating independently or in combination. This segmentation allows the system to use only the necessary amplification capacity for current operating conditions, avoiding the energy waste of running a single large amplifier at low power levels.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically switches between different operating modes: single-chain mode for low to medium power levels and dual-chain mode for maximum power levels. This dynamic reconfiguration optimizes efficiency by matching the amplification resources to the actual power requirements, preventing unnecessary energy consumption at lower output levels.

Inventive Principle:

Principle #15Dynamics

3Device complexity

If a single power amplifier design is used to support multiple radio technologies and frequency bands, then device complexity is reduced, but efficiency deteriorates due to inability to optimize for specific operating conditions

Engineering Contradiction:

Improvenumber of power amplifiersVSAvoidpower consumption

Core Design Contradiction:

Device complexityVSLoss of energy

Solution Approach 1:

The power amplifier is divided into multiple parallel chains (first linear power amplifier and second linear power amplifier), each capable of operating independently or in combination. This segmentation allows the system to use only the necessary amplification capacity for current operating conditions, avoiding the energy waste of running a single large amplifier at low power levels.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically switches between different operating modes: single-chain mode for low to medium power levels and dual-chain mode for maximum power levels. This dynamic reconfiguration optimizes efficiency by matching the amplification resources to the actual power requirements, preventing unnecessary energy consumption at lower output levels.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS8718582B2Multi-mode power amplifiers

Publication Date: 2014.05.06 QUALCOMM INC

AI summary

Multi-mode power amplifiers that can support multiple radio technologies and/or multiple frequency bands are described. In one exemplary design, a first linear power amplifier supporting multiple radio technologies may be used to amplify a first RF input signal (e.g., for low band) and provide a first RF output signal. A second linear power amplifier also supporting the multiple radio technologies may be used to amplify a second RF input signal (e.g., for high band) and provide a second RF output signal. Each linear power amplifier may include multiple (e.g., three) chains coupled in parallel. Each chain may be selectable to amplify an RF input signal and provide an RF output signal for a respective range of output power levels. An RF input signal may be a phase modulated signal or a quadrature modulated signal and may be pre-distorted to account for non-linearity of the power amplifier.