Underwater quantum distance measurement method based on starry sea light quantum link transmission

Abstract

The invention provides an underwater quantum distance measurement method based on starry sea light quantum link transmission. The method comprises the following steps: firstly, establishing a light quantum communication link by utilizing an aiming tracking technology, generating pump light through a laser on a satellite, enabling the pump light to enter a periodically poled potassium titanyl phosphate crystal, carrying out spontaneous parametric down-conversion to obtain signal light and idle light with entanglement characteristics, and respectively transmitting the signal light and the idle light to a sea surface station 1 and a sea surface station 2; using single-photon detectors of the two sea surface stations to receiving photons; secondly, enabling the sea surface station 1 to sink, enabling the sea surface station 2 to float on the sea surface, and tracking the position of the sea surface station 1; then, using a single-photon detector on the sea surface station 1 to emit photons to a target, and receiving the photons by the single-photon detector after the photons are reflected by the target; and finally, performing coincidence counting is performed on the time pulse sequences output by the single-photon detectors of the two sea surface stations by using a high-speed acquisition circuit, obtaining the flight time of the signal light, and further calculating the distance between the sea surface station 1 and the target.

Description

technical field [0001] The invention relates to the field of high-precision ranging of underwater targets, in particular to an underwater quantum ranging method based on Xinghai optical quantum link transmission. Background technique [0002] The traditional underwater ranging technology mainly uses laser and ultrasonic to measure the distance of the target. The principle is to transmit the ranging signal to the target and reflect it back to the transmitter to obtain the time difference from the transmitter to the target, and then calculate the available transmitter. distance to the target. Traditional underwater laser ranging technology is easily affected by signal stability and multipath propagation of light, and is not suitable for long-distance measurement. In addition, the underwater ultrasonic ranging is caused by the change of sound velocity caused by the pressure and temperature in the turbulent environment, which causes a large error between the measured distance a...

AI Technical Summary

Problems solved by technology

Traditional underwater laser ranging technology is easily affected by signal stability and multipath propagation of light, and is not suitable for long-distance measurement

In addition, underwater ultrasonic distance measurement has a large error between the measured distance and the actual distance due to the change of sound velocity caused by the pressure and temperature in the turbulent environment.

Traditional underwater ranging technology has problems such as low accuracy and limited measurement range, which restricts the improvement of the Chinese navy's detection level of underwater targets.

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