Resonant type magnetic sensor

Abstract

The invention discloses a resonant type magnetic sensor. The resonant type magnetic sensor comprises a resonance unit, a magnetostriction material and an excitation frequency measurement device, wherein the resonance unit comprises two resonators which have the same structure and are connected symmetrically, the resonators are respectively provided with a positive electrode and share one negativeelectrode, and the resonators are connected with the excitation frequency measurement device through the positive electrodes and the negative electrode, not only can generate resonant vibration, but also can improve signal-to-noise ratio of the resonant type magnetic sensor through improving a Q value of the resonators; under the action of an external magnetic field, the magnetostriction materialgenerates change of strain and elasticity modulus, consequently, changes a work state of the resonance unit; and the excitation frequency measurement device measures change of resonant frequency of the resonators to measure amplitude and frequency of external magnetic field signals. With the resonant type magnetic sensor, a problem of low resolution of output signals of the existing resonant sensor caused by failure in suppression of low-frequency intrinsic noise of a system is solved.

Description

technical field [0001] The invention belongs to the field of magnetic sensors, and more specifically relates to a resonant magnetic sensor. Background technique [0002] Magnetic sensors are widely used and have played an important role in the fields of industry, national defense, science and technology, and medical treatment. They are a major branch of the modern sensor industry. Especially vector magnetic sensors, such as Hall sensors, anisotropic magnetoresistance sensors (AMR), giant magnetoresistance sensors (GMR), tunnel magnetoresistance sensors (TMR), giant magnetoimpedance sensors GMI and magnetoelectric sensors and other micro sensors , because of its low price, small size, and low power consumption, it is widely used in low-cost current measurement, position detection, speed detection, hard disk magnetic head, non-destructive testing, etc. However, with the further widespread application in hand-held devices such as mobile phones, the problems of power consumptio...

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Problems solved by technology

[0005] In view of the defects of the prior art, the object of the present invention is to provide a resonant magnetic sensor, aiming to solve the problem of low output signal resolution caused by the inability of the existing resonant sensor to suppress the low-frequency intrinsic noise of the system

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