Frequency estimation method for free induction decay signal of proton magnetometer based on IpDFT

Abstract

The invention discloses a frequency estimation method for free induction decay signal of proton magnetometer based on IpDFT. The proton magnetometer type quantum weak magnetic measurement instrument is the most ancient instrument and has become one of the most widely used geomagnetic measurement instruments for the half century due to the advantages of simplicity in operation, good stability and the like. The precision of a derived magnetic field is determined by the precision of free induction decay signal frequency measurement in the proton magnetometer. Therefore, the method has important significance for research on high-precision frequency estimation. According to the method provided by the invention, estimation precision of the algorithm is improved, the signal frequency can be estimated within a short time, and in the environment with a low signal-to-noise ratio, higher estimation accuracy is still achieved.

Description

technical field [0001] The invention relates to the field of geomagnetic measurement, in particular to a method for estimating the frequency of a free induction attenuation signal of a proton magnetometer based on IpDFT in a reverse power supply protection device for a power grid. Background technique [0002] The proton magnetometer is the oldest instrument in the history of quantum weak magnetic measuring instruments. Due to its advantages of simple operation and good stability, it has become one of the most widely used geomagnetic measuring instruments for half a century. The traditional proton magnetometer has a resolution of 0.1nT and an accuracy of 1.0nT. The pendant magnetometer can obtain higher precision, the precision is 0.1nT, and the resolution is 0.01nT. Although pendant magnetometers are more accurate, more sensitive, and lower power than proton magnetometers, they have some disadvantages. Polarization of radical solutions in a pendant magnetometer probe alwa...

AI Technical Summary

Problems solved by technology

However, these algorithms have some shortcomings. Some algorithms have relatively large computational complexity and cannot estimate the signal frequency in a short time. Some algorithms have poor anti-noise performance and poor estimation accuracy when the signal-to-noise ratio is relatively small.

At present, there are two main difficulties in FID signal frequency estimation. Due to the fast attenuation of FID signal and the limited frequency measurement time, how to achieve high measurement accuracy in a short time is still a problem to be solved; further improving the low signal-to-noise ratio The measurement accuracy of the frequency in the environment is another problem to be solved

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