Multi-peak closed-loop CPT magnetic force measurement method without direction blind area

Abstract

The invention relates to a multi-peak closed-loop CPT magnetometer measurement method without a direction blind area, and belongs to the field of microwave frequency locking of CPT magnetometers. Themethod comprises the following steps: 1, inputting a generated single-frequency microwave signal and a modulation signal into a laser device, and modulating laser emitted by the laser device; 2, transmitting the modulated laser into a glass air chamber, and demodulating an EIT signal by measuring the change of the power of transmitted light; 3, sequentially changing the center frequency of the microwave signal; 4, sequentially obtaining differential signals of the EIT signals under different center frequencies of the microwave signals by adopting a phase-sensitive detection method; 5, calculating a total error signal P '(B); 6, adjusting an external to-be-measured magnetic field value B through a digital PID controller, and enabling the total error signal P '(B) to be zero. The value B isthe to-be-measured magnetic field value. According to the CPT magnetometer without the direction blind area, a measurement mode does not need to be switched when the direction of the magnetic field ischanged, and continuous measurement of the magnetic field can be guaranteed.

Description

technical field [0001] The invention belongs to the microwave frequency locking field of a CPT magnetometer, and relates to a multi-peak closed-loop non-directional blind zone CPT magnetometer measurement method. Background technique [0002] The CPT magnetometer has the characteristics of small size, low power consumption, high precision, and no direction blind zone. It is expected to replace the optical pump magnetometer and be used in the fields of space magnetic measurement, marine magnetic measurement, and aerial magnetic measurement. [0003] The CPT magnetometer is based on the Zeeman splitting phenomenon of the atomic fine structure energy level in the magnetic field, and realizes the measurement of the magnetic field by detecting the transmission spectral characteristics caused by the interference between the two transition channels of the atom. In the ∧-type three-level system, the energy level |1>, |2> is the ground state energy level, and |3> is the exci...

AI Technical Summary

Problems solved by technology

If the magnetic field is only measured by locking the two EIT signal peaks, if the direction of the laser and the magnetic field changes, the two locked EIT signals may disappear. At this time, the magnetometer works abnormally, that is, the magnetometer has a measurement blind area.

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