Doherty Power Amplifier Isolation Resistor Switching for Lower Power Use
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Solution Overview
Problem
As the number of antennas and RF components increases in communication systems, the efficiency and power consumption of power amplifiers become significant challenges, particularly in systems with multiple antennas and Doherty power amplifiers.
Innovation Solution
The implementation of a Doherty power amplifier with a resistor selection circuit that allows for an isolation resistor with an impedance lower than the reference impedance, coupled with a coupler to improve efficiency and reduce power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the number of antennas and RF components is increased to improve communication performance, then communication performance is improved, but power consumption increases and efficiency decreases
Solution Approach 1:
The patent changes the impedance parameter of the isolation resistor from the conventional 50 ohms to a lower value (25-40 ohms). This parameter change optimizes the power distribution in the Doherty amplifier, allowing the carrier amplifier to receive more power and operate more efficiently, thereby reducing overall power consumption while maintaining communication performance
Solution Approach 2:
The patent introduces a resistor selection circuit that can dynamically switch between different impedance values (25 ohms, 30 ohms, 35 ohms, 40 ohms) based on operating conditions. This dynamic adjustment allows the system to optimize efficiency across different power levels and communication scenarios, resolving the contradiction between performance and power consumption
2Manufacturing precision
If the isolation resistor impedance is set to conventional 50 ohms for impedance matching, then impedance matching is achieved, but power amplifier efficiency is limited
Solution Approach 1:
The patent fundamentally changes the isolation resistor impedance parameter from 50 ohms to lower values (25-40 ohms). This breaks the conventional impedance matching rule but optimizes power distribution to the carrier amplifier, significantly improving power amplifier efficiency while maintaining adequate impedance matching through the resistor selection circuit
Solution Approach 2:
The resistor selection circuit provides dynamic impedance adjustment, allowing the system to switch between multiple impedance values (25, 30, 35, 40 ohms) depending on operating conditions. This dynamic capability enables the system to maintain optimal efficiency across varying power levels while preserving sufficient impedance matching characteristics
Data Source
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AI summary
Provided in embodiments is an electronic device for a Doherty power amplifier. The electronic device may comprise: a coupler for acquiring a radio frequency (RF) input signal; a power amplifier circuit including a carrier amplifier circuit and a peaking amplifier circuit; and a resistor selection circuit for providing isolation impedance from among a plurality of impedances to the coupler.