Magnetoresistance Mixer with Tunable Frequency Selectivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current mixers using magnetoresistance effect elements face challenges in achieving high Q factor resonance characteristics and frequency selectivity, leading to attenuation of multiplication signals and limited industrial application.
Innovation Solution
A mixer design incorporating a magnetoresistance effect element with a pinned and free magnetization layer, a magnetic-field applying unit, and a frequency selective attenuator, where the resonant frequency of the magnetoresistance effect element is set to coincide with the local signal frequency, and the first high frequency signal is near the local signal frequency, utilizing an impedance circuit to enhance signal strength and frequency selectivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a magnetoresistance effect element is used in a mixer, then power consumption is reduced, but the multiplication signal attenuates when passing through the matching circuit
Solution Approach 1:
An impedance circuit is introduced as an intermediary component between the magnetoresistance effect element and the matching circuit. This impedance circuit has high impedance at the multiplication signal frequency, preventing signal attenuation while allowing the low-power benefits of the magnetoresistance effect element to be maintained.
Solution Approach 2:
The impedance characteristics of the circuit are changed by frequency. The impedance circuit is designed to have high impedance specifically at the multiplication signal frequency, creating a frequency-selective parameter change that protects the multiplication signal from attenuation while maintaining proper matching for other frequencies.
2Reliability
If existing oscillation resonators (SAW, BAW) are used, then frequency filtering is provided, but they cannot achieve high Q factor resonance or tunable frequency requirements
Solution Approach 1:
The system transitions from static resonators with fixed frequencies to a dynamic system using a magnetoresistance effect element where the resonant frequency can be tuned by adjusting the magnetic field applied to the free magnetization layer, enabling adaptive frequency selection while maintaining high Q factor resonance characteristics.
Solution Approach 2:
The physical parameters of the magnetoresistance effect element are changed by applying different magnetic fields to the free magnetization layer, which alters the spin precession frequency and thus the resonant frequency of the element, enabling tunable frequency operation while maintaining high Q factor.
3Measurement precision
If the resonant frequency of the magnetoresistance effect element is set to coincide with the local signal frequency, then frequency selectivity is improved, but the first high frequency signal must be precisely controlled near the local signal frequency
Solution Approach 1:
The system uses the strong resonance occurrence at the spin precession frequency as a feedback mechanism. When the local signal frequency matches the resonant frequency of the magnetoresistance effect element, the resonance is maximized, providing natural frequency alignment and selectivity without requiring complex external frequency control mechanisms.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design achieves a high Q factor, improving the frequency selectivity of the band-pass filter function, increasing the multiplication signal strength, and reducing power consumption by minimizing signal attenuation, enabling effective industrial application.
Implementation Method 1
a magnetoresistance effect element that includes a pinned magnetization layer, a free magnetization layer, and a non-magnetic spacer layer disposed between the pinned magnetization layer and the free magnetization layer, and that generates, in response to an input of a first high frequency signal S1 and a second high frequency signal S2 for a local signal, a multiplication signal by multiplying both the high frequency signals by each other using a magnetoresistance effect
Implementation Method 2
a magnetic-field applying unit that applies a magnetic field to the free magnetization layer
Implementation Method 3
a frequency selective attenuator that exhibits frequency selectivity for the multiplication signal by using the maximum strength of the multiplication signal generated when a resonant frequency f0 of the magnetoresistance effect element is set to coincide with the frequency f2 of the second high frequency signal S2 for a local signal
Data Source
AI summary
In order to provide a mixer capable of extracting a high multiplication signal and which has a reception band-pass filter function, a magnetoresistance effect element is provided that includes a pinned magnetization layer, a free magnetization layer, and a non-magnetic spacer layer disposed between the pinned magnetization layer and the free magnetization layer. This allows for a frequency converter which implements a desired band-pass filter by controlling a magnetic field applied by a magnetic-field applying unit to be provided.