Composite Power Amplifier Driver Circuit With Fixed-Phase Signal Splitting

Solution Overview

Problem

Existing power amplifiers for wireless communication systems suffer from high complexity and cost, requiring external control and feedback, which complicates the generation of drive signals for efficient operation.

Innovation Solution

A driver circuit for a composite power amplifier that splits an input signal into two parts, where one signal is linearly derivable and the other non-linearly derivable, combined with fixed phase relationships to generate feeding signals for sub-amplifiers, eliminating the need for complex voltage-to-phase conversion and control circuitry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If external control and feedback circuits are used to generate drive signals for composite power amplifier, then the phase and amplitude control precision is improved, but the device complexity and cost increase

Engineering Contradiction:

Improvephase and amplitude control precisionVSAvoiddevice complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The input network automatically generates the required drive signals with correct phases and amplitudes by utilizing the inherent properties of the network components and signal flow, without requiring external control or feedback circuits. The network self-adjusts to provide the appropriate signal characteristics for efficient power amplifier operation.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The complex voltage-to-phase conversion and control circuitry is extracted and removed from the system. Instead of using external control circuits, the patent uses a simplified input network that directly generates the necessary drive signals through its passive component configuration, eliminating the need for separate control systems.

Inventive Principle:

Principle #2Taking out (Extraction)

2Productivity

If voltage-to-phase conversion and control circuitry are added to generate drive signals, then the operational efficiency of power amplifier is improved, but the manufacturing cost and complexity increase

Engineering Contradiction:

Improveoperational efficiencyVSAvoidmanufacturing cost

Core Design Contradiction:

ProductivityVSEase of manufacture

Solution Approach 1:

The input network automatically generates the required drive signals with correct phases and amplitudes by utilizing the inherent properties of the network components and signal flow, without requiring external control or feedback circuits. The network self-adjusts to provide the appropriate signal characteristics for efficient power amplifier operation.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces expensive active control circuitry with simple passive network components (inductors, capacitors, transmission lines) that are inexpensive to manufacture. These passive components achieve the same functional result without requiring complex voltage-to-phase converters or control systems.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Measurement precision

If complex drive signal generation with multiple control circuits is implemented, then the amplitude and phase accuracy is improved, but the power consumption and hardware cost increase

Engineering Contradiction:

Improveamplitude and phase accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The input network automatically generates the required drive signals with correct phases and amplitudes by utilizing the inherent properties of the network components and signal flow, without requiring external control or feedback circuits. The network self-adjusts to provide the appropriate signal characteristics for efficient power amplifier operation.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces active electronic control systems (which consume power) with passive network components that manipulate signals through their physical structure. The phase and amplitude control is achieved through the natural impedance and phase characteristics of the network components rather than through active control circuits.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP3205017B1Driver circuit for composite power amplifier

Publication Date: 2019.05.15 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

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AI summary

A driver circuit (100) for a composite power amplifier configured to operate in at least one Chireix-mode a first and a second sub-amplifier (111, 112) for amplification of an input signal into an output signal is disclosed. An input network (120) of the driver circuit (100) comprises a means (130) configured to provide a first signal which is linearly derivable from the input signal, and a second signal which is non-linearly derivable from the input signal. The input network (100) combines the first signal, at zero degrees phase shift, and the second signal, at 90 degrees phase shift, to obtain a first feeding signal for the first sub-amplifier (111). Furthermore, the input network (100) combines the first signal, at 180 degrees phase shift, and the second signal, at 90 degrees phase shift, to obtain a second feeding signal for the second sub-amplifier (112).