Quadrature RF Phase Shifter With Fine Steps and Stable Amplitude
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Solution Overview
Problem
Existing phase shifting devices are limited by large phase steps, significant amplitude variation over phase steps, and high power consumption, which hinders their efficiency and compactness in applications like phased array systems.
Innovation Solution
A phase shifting device comprising a common source input amplifier, common gate output amplifiers, and a differential quadrature hybrid coupler, configured in a cascode arrangement with variable-gain amplifiers and a biasing circuit to achieve reduced power consumption and multilevel modulation, allowing for smaller phase steps and stable amplitude.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional phase shifting devices are used, then phase shifting function is provided, but the phase steps are large and amplitude variation is significant
Solution Approach 1:
The phase shifting device is segmented into multiple independent variable-gain amplifier channels (through port channel and coupled port channel), each capable of independent amplitude control. This segmentation allows fine-grained adjustment of phase steps while maintaining stable output amplitude through coordinated control of both channels.
Solution Approach 2:
The patent employs variable-gain amplifiers with dynamically adjustable gain values in both the through port channel and coupled port channel. This dynamic adjustment capability enables continuous phase shifting with small phase steps while compensating for amplitude variations in real-time to maintain stable output.
2Reliability
If conventional phase shifting devices are used, then phase shifting is achieved, but power consumption is high
Solution Approach 1:
The patent merges the phase shifting function with variable gain control in a unified architecture using a quadrature hybrid coupler combined with variable-gain amplifiers. This integration allows simultaneous control of phase and amplitude with shared signal paths and control mechanisms, reducing overall power consumption while maintaining reliable phase shifting performance.
Solution Approach 2:
The patent changes the operating parameters of the amplifiers by implementing variable gain control through digital-to-analog converters and bias control circuits. This allows the system to operate at optimal power levels for different phase shifting requirements, reducing power consumption while maintaining the necessary phase shifting reliability.
3Adaptability or versatility
If conventional phase shifting devices are used, then phase shifting function is provided, but the device size is large
Solution Approach 1:
The patent implements a multi-functional architecture where the quadrature hybrid coupler serves both signal splitting and phase shifting functions, while the variable-gain amplifiers provide both amplitude control and phase adjustment capabilities. This universality reduces the need for separate dedicated components, thereby reducing overall device area while maintaining full phase shifting capability.
Data Source
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AI summary
A phase shifting device is disclosed, comprising an input amplifier (110), a biasing circuit (120), a first output amplifier (130) and a second output amplifier (140) being variable-gain amplifiers, and a quadrature hybrid coupler (150). The input amplifier is connected to an input port (P1) of the coupler, the first output amplifier is connected to a through port (P2) of the coupler, the second output amplifier is connected to a coupled port (P3) of the coupler, and the biasing circuit is connected to an isolated port (P4) of the coupler. Further, the quadrature hybrid coupler is configured to receive, at the input port, an input signal (IN) from the input amplifier, output, at the through port, a through signal (I), receive, at the isolated port, a bias signal from the biasing circuit, and output, at the coupled port, a coupled signal (Q) having a phase differing from a phase of the through signal.