Ocean turbulence channel quantum key distribution system and distribution method

Abstract

The present invention discloses a quantum key distribution system for an ocean turbulent channel, including a quantum key transmitter and a quantum key receiver, both of which are arranged in an ocean turbulent channel; the quantum key transmitter is used to modulate a classical signal, and the modulated classical signal is superimposed with a quantum signal and then sent to the quantum key receiver through a quantum channel; the quantum key receiver is used to realize real-time detection of distorted wavefronts, correct wavefront distortion caused by high-order wavefront aberrations, and realize key negotiation and private amplification with the quantum key transmitter through subsequent detection, so as to complete the distribution of quantum keys. The present invention also discloses a distribution method for the ocean turbulent channel quantum key distribution system. The present invention adopts a piezoelectric fast steering mirror module at the receiving end to reduce beam jitter, and adopts an optical module at the receiving end to realize real-time detection of distorted wavefronts, correct wavefront distortion caused by high-order wavefront aberrations, thereby improving the performance of the system, and having high reliability, good practicality and a wide range of applications.

Description

Technical Field

[0001] The present invention belongs to the field of quantum communication, and in particular relates to an ocean turbulence channel quantum key distribution system and a distribution method thereof. Background Art

[0002] With the development of economy and technology and the improvement of people's living standards, people have higher and higher requirements for the security of the communication process. Therefore, ensuring the security of the communication process has become the focus of researchers.

[0003] Quantum key distribution is a secure way to transmit keys; the quantum key distribution system can send keys between two distant communication terminals. In the process of confidential communication, keys are needed to encrypt and decrypt information, and the security of the keys ensures the security of the information. Unlike traditional methods, quantum key distribution is theoretically unconditionally secure, and its security is guaranteed by the basic principles of quantum mechanics. Generally speaking, the transmission of quantum states in the process of quantum key distribution is achieved by encoding, transmitting, and measuring photons. So far, quantum key distribution technology has been widely studied and has become a well-developed technology in the world of display applications.

[0004] Quantum key distribution technology has been widely used in ground links and satellite-to-ground links. However, due to the special composition and optical properties of seawater, there is currently little research on quantum key distribution technology in ocean turbulence channels. Due to the severe ocean optical turbulence, the light beam is prone to jitter and the wavefront and amplitude of the laser carrier signal are easily distorted, which will reduce the performance of the quantum key distribution system. As a result, there is no good ocean turbulence channel quantum key distribution system and its corresponding distribution method. Summary of the invention

[0005] One of the purposes of the present invention is to provide a quantum key distribution system for an ocean turbulent channel with high reliability, good practicability and wide application range.

[0006] A second object of the present invention is to provide a distribution method for the ocean turbulent channel quantum key distribution system.

[0007] The ocean turbulent channel quantum key distribution system provided by the present invention comprises a quantum key transmitter and a quantum key receiver; both the quantum key transmitter and the quantum key receiver are arranged in the ocean turbulent channel; the quantum key transmitter is used to modulate a classical signal, and after superimposing the modulated classical signal with a quantum signal, sends the signal to the quantum key receiver through a quantum channel; the quantum key receiver is used to realize real-time detection of distorted wavefronts, correct wavefront distortion caused by high-order wavefront aberrations, and realize key negotiation and private amplification with the quantum key transmitter through subsequent detection, thereby completing the distribution of quantum keys.

[0008] The quantum key transmitter comprises a transmitter pulse laser, a transmitter signal generation module, a transmitter electro-optical phase modulation and amplitude modulator, a transmitter variable optical attenuator and a transmitter collimator; the transmitter pulse laser, the transmitter electro-optical phase modulation and amplitude modulator, the transmitter variable optical attenuator and the transmitter collimator are sequentially connected in series, and the output end of the transmitter signal generation module is connected to the input end of the transmitter electro-optical phase modulation and amplitude modulator; the transmitter pulse laser is used to generate optical pulses, and the generated optical pulses are sent to the transmitter electro-optical phase modulation and amplitude modulator; the transmitter signal generation module is used to generate analog signals and QPSK superimposes uniformly distributed analog signals and sends them to the transmitting end electro-optical phase modulation and amplitude modulator, wherein the analog signal obeying the Rayleigh distribution is used to modulate the light field intensity, and QPSK superimposes uniformly distributed analog signals to modulate the light field phase; the transmitting end electro-optical phase modulation and amplitude modulator is used to simultaneously perform QPSK and Gaussian modulation on the received optical pulses, and send the modulated signal to the transmitting end variable optical attenuator; the transmitting end variable optical attenuator is used to attenuate the energy of the received signal light to the expected coherent state, and send it to the transmitting end collimator; the transmitting end collimator is used to send the received optical signal to the quantum key receiving end through the quantum channel.

[0009] The transmitting end electro-optical phase modulation and amplitude modulator includes a transmitting end electro-optical phase modulator and a transmitting end amplitude modulator. The transmitting end electro-optical phase modulator is an electro-optical phase modulator of model MPZ-LN-10, and the transmitting end amplitude modulator is an amplitude modulator of model MX-LN-10; the transmitting end pulse laser is a picosecond optical pulse generator of model OPG1015; and the transmitting end signal generation module is an FPGA signal generation card of model Xilinx VC707.

[0010] The quantum key receiving end comprises a receiving end collimator, a receiving end piezoelectric fast steering mirror module, a receiving end optical module, a receiving end signal detection module and a receiving end data acquisition module; the receiving end collimator, the receiving end piezoelectric fast steering mirror module, the receiving end optical module, the receiving end signal detection module and the receiving end data acquisition module are connected in series in sequence; the receiving end collimator is used to receive the signal sent by the quantum signal sending end through the quantum channel, and upload it to the receiving end piezoelectric fast steering mirror module; the receiving end piezoelectric fast steering mirror module is used to measure, feedback and split the received signal, and upload the signal to the receiving end optical module; the receiving end optical module is used to detect, correct and split the received signal, and upload the signal to the receiving end signal detection module; the receiving end signal detection module is used to generate local local oscillator light, and perform coherent mixing and homodyne detection on the local oscillator light and the received signal, and upload the signal to the receiving end data acquisition module; the receiving end data acquisition module is used to receive the signal.

[0011] The receiving end piezoelectric fast steering mirror module comprises a steering mirror four-phase controller, a steering mirror FSM controller, a steering mirror FSM reflector and a steering mirror beam splitter; the output end of the steering mirror four-phase controller, the steering mirror FSM controller, the steering mirror FSM reflector and the input end of the steering mirror beam splitter are connected in series in sequence; the first input end of the steering mirror four-phase controller is connected to the receiving end collimator, the second input end of the steering mirror four-phase controller is connected to the first output end of the steering mirror beam splitter, and the second output end of the steering mirror beam splitter is connected to the receiving end optical module; the steering mirror four-phase controller is used to receive the light beam uploaded by the receiving end collimator The steering mirror FSM controller is used to read the signal, send the control signal to control the FSM reflector, and also forward the light beam signal to the steering mirror FSM reflector; the steering mirror FSM reflector is used to adjust the reflection angle, correct the received light beam, and send the corrected light beam to the self-steering mirror beam splitter; the steering mirror beam splitter is used to split the received light beam into two paths, and the 1% light beam is used for feedback control by the steering mirror four-phase controller; the 99% light beam is sent to the receiving end optical module.

[0012] The receiving end optical module comprises an optical module wavefront sensor, an optical module wavefront controller, an optical module wavefront corrector and an optical module beam splitter; the input ends of the optical module wavefront sensor, the optical module wavefront controller, the optical module wavefront corrector and the optical module beam splitter are connected in series in sequence; the first output end of the optical module beam splitter is connected to the optical module wavefront controller, and the second output end of the optical module beam splitter is connected to the receiving end signal detection module; the optical module wavefront sensor is used to receive signals, measure the wavefront aberration of the light beam as a feedback signal, and send it to the optical module wavefront controller; the optical module wavefront controller is used to control the optical module wavefront corrector according to the feedback signal uploaded by the optical module beam splitter, and also forward the light beam signal to the optical module wavefront corrector; the optical module wavefront corrector is used to perform wavefront correction on the received light beam signal, and send the corrected signal to the optical module beam splitter; the optical module beam splitter is used to divide the received light beam signal into two paths, 1% of the light beam signal is uploaded to the optical module wavefront controller as a feedback signal, and 99% of the light beam signal is uploaded to the receiving end signal detection module.

[0013] The receiving end signal detection module comprises a first polarization controller for signal detection, a 90° optical mixer for signal detection, a local oscillator for signal detection, a second polarization controller for signal detection and a homodyne detector for signal detection; the output end of the first polarization controller for signal detection is connected to the first input end of the 90° optical mixer for signal detection; the local oscillator for signal detection and the second polarization controller for signal detection are connected in series; the output end of the second polarization controller for signal detection is connected to the second input end of the 90° optical mixer for signal detection; the output end of the 90° optical mixer for signal detection is connected to the input end of the homodyne detector for signal detection, and the output end of the homodyne detector for signal detection is connected to the receiving end data acquisition module; the first polarization controller for signal detection is connected to the first input end of the 90° optical mixer for signal detection; the output end of ... to the receiving end data acquisition module; the first polarization controller for signal detection is connected to the first input end of the 90° optical mixer for signal detection; the output end of the local oscillator for signal detection and the second polarization controller for signal detection are connected to the receiving end data acquisition module; the first polarization controller for signal detection is connected to the first input end of the 90° optical mixer for signal detection; the output end of the local oscillator for signal detection and the second polarization controller for signal detection are connected to the receiving end data The polarization of the signal light beam uploaded by the optical module at the receiving end is corrected, and the corrected signal light beam is sent to the signal detection 90° optical mixer; the signal detection local oscillator is used to generate a local local oscillation light signal and upload it to the signal detection second polarization controller; the signal detection second polarization controller is used to receive the local local oscillation light signal, and send the local oscillation light signal to the signal detection 90° optical mixer after polarization correction; the signal detection 90° optical mixer is used to mix the received local oscillation light and the signal light, and send the mixed signal to the signal detection homodyne detector; the signal detection homodyne detector is used to perform homodyne detection on the received signal, and upload the detection result to the receiving end data acquisition module.

[0014] The receiving end data acquisition module is an FPGA data acquisition card with the model number ADS8-V1EBZ; the signal detection homodyne detector is a balanced amplified photoelectric detector with the model number Optilab EPR-23-M.

[0015] The present invention also provides a distribution method of the ocean turbulence channel quantum key distribution system, which specifically comprises the following steps:

[0016] S1. The quantum signal transmitter generates an optical pulse and a modulation signal, performs QPSK and Gaussian modulation on the optical pulse according to the generated modulation signal, decays the modulated signal to the expected coherent state, and sends it to the quantum signal receiver through the quantum channel;

[0017] S2. After receiving the signal, the quantum signal receiving end measures the elevation and azimuth angles of the light beam through the piezoelectric fast steering mirror module at the receiving end, and corrects the light beam;

[0018] S3. The quantum signal receiving end performs wavefront correction on the corrected light beam again through the receiving end optical module to obtain a signal light beam;

[0019] S4. The quantum signal receiving end generates a local light beam, and after coherent mixing and homodyne detection with the signal beam obtained in step S3, the detection result is collected for data;

[0020] S5. Based on the collected signal, the quantum key receiver conducts key negotiation and private amplification with the quantum key sender, and finally completes the distribution of the quantum key.

[0021] The ocean turbulence channel quantum key distribution system and distribution method provided by the present invention aims to solve the problem that the mixing efficiency of heterodyne detection is reduced due to the light beam jitter and wavefront distortion caused by high-order wavefront aberrations caused by the existence of ocean optical turbulence. A piezoelectric fast steering mirror module is used at the receiving end to reduce the light beam jitter, and an optical module is used at the receiving end to realize real-time detection of the distorted wavefront and correct the wavefront distortion caused by high-order wavefront aberrations, thereby improving the performance of the ocean turbulence channel quantum key distribution fusion classical system. Therefore, the present invention has high reliability, good practicality and wide application range. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a functional module diagram of the system of the present invention.

[0023] Figure 2 This is a functional module diagram of the quantum key sending end of the system of the present invention.

[0024] Figure 3 This is a functional module diagram of the quantum key receiving end of the system of the present invention.

[0025] Figure 4 This is a functional module diagram of a receiving-end piezoelectric fast-steering mirror module of a quantum key receiving end of the system of the present invention.

[0026] Figure 5This is a functional module diagram of the receiving end optical module of the quantum key receiving end of the system of the present invention.

[0027] Figure 6 This is a functional module diagram of a receiving-end signal detection module of a quantum key receiving end of the system of the present invention.

[0028] Figure 7 The figure is a schematic diagram of the method flow of the present invention. DETAILED DESCRIPTION

[0029] like Figure 1 The functional module diagram of the system of the present invention is shown as follows: the ocean turbulent channel quantum key distribution system provided by the present invention includes a quantum key transmitter and a quantum key receiver; the quantum key transmitter and the quantum key receiver are both arranged in the ocean turbulent channel; the quantum key transmitter is used to modulate the classical signal, and after superimposing the modulated classical signal on the quantum signal, send it to the quantum key receiver through the quantum channel; the quantum key receiver is used to realize real-time detection of the distorted wavefront, correct the wavefront distortion caused by high-order wavefront aberrations, and realize key negotiation and private amplification with the quantum key transmitter through subsequent detection, thereby completing the distribution of quantum keys.

[0030] like Figure 2 The figure shows the functional module diagram of the quantum key transmitter of the system of the present invention: the quantum key transmitter includes a transmitter pulse laser, a transmitter signal generation module, a transmitter electro-optical phase modulation and amplitude modulator, a transmitter variable optical attenuator and a transmitter collimator; the transmitter pulse laser, the transmitter electro-optical phase modulation and amplitude modulator, the transmitter variable optical attenuator and the transmitter collimator are connected in series in sequence, and the output end of the transmitter signal generation module is connected to the input end of the transmitter electro-optical phase modulation and amplitude modulator; the transmitter pulse laser is used to generate optical pulses, and send the generated optical pulses to the transmitter electro-optical phase modulation and amplitude modulator; the transmitter signal generation module is used to generate an optical pulse that obeys The Rayleigh distributed analog signal and the QPSK superimposed uniformly distributed analog signal are sent to the transmitting end electro-optical phase modulation and amplitude modulator, wherein the analog signal obeying the Rayleigh distribution is used to modulate the light field intensity, and the QPSK superimposed uniformly distributed analog signal is used to modulate the light field phase; the transmitting end electro-optical phase modulation and amplitude modulator is used to simultaneously perform QPSK and Gaussian modulation on the received optical pulse, and send the modulated signal to the transmitting end variable optical attenuator; the transmitting end variable optical attenuator is used to attenuate the energy of the received signal light to the expected coherent state, and send it to the transmitting end collimator; the transmitting end collimator is used to send the received optical signal to the quantum key receiving end through the quantum channel.

[0031] In specific implementation, the transmitting end electro-optical phase modulation and amplitude modulator includes a transmitting end electro-optical phase modulator and a transmitting end amplitude modulator. The transmitting end electro-optical phase modulator is an electro-optical phase modulator of model MPZ-LN-10, which has the characteristics of high extinction ratio (>20dB), low loss (2.5dB), and high bandwidth (10GHz), and can meet the higher rate of quantum key distribution fusion classical communication system, and minimize the additional loss caused by optical devices; the transmitting end amplitude modulator is an amplitude modulator of model MX-LN-10, which has the characteristics of high extinction ratio (>20dB), low loss (2.5dB), and high bandwidth (10GHz); the transmitting end pulse laser is a picosecond optical pulse generator of model OPG1015, which can generate laser pulses less than or equal to 3ps and a frequency of 10GHz; the transmitting end signal generation module is an FPGA signal generation card of model Xilinx VC707, which has two DAs, both of which can reach a sampling rate of more than 10GSa / s. Among them, the modulation signal required by the quantum key transmitter generated by the FPGA signal generation card includes an analog signal whose voltage value obeys the Rayleigh distribution and an analog signal whose voltage value obeys the QPSK superposition uniform distribution; the analog signal whose voltage value obeys the Rayleigh distribution is used for amplitude modulation, and the analog signal whose voltage value obeys the QPSK superposition uniform distribution is used for the phase modulator.

[0032] like Figure 3 The figure shows a functional module diagram of the quantum key receiving end of the system of the present invention: the quantum key receiving end includes a receiving end collimator, a receiving end piezoelectric fast steering mirror module, a receiving end optical module, a receiving end signal detection module and a receiving end data acquisition module; the receiving end collimator, the receiving end piezoelectric fast steering mirror module, the receiving end optical module, the receiving end signal detection module and the receiving end data acquisition module are connected in series in sequence; the receiving end collimator is used to receive the signal sent by the quantum signal sending end through the quantum channel, and upload it to the receiving end piezoelectric fast steering mirror module; the receiving end piezoelectric fast steering mirror module is used to measure, feedback and split the received signal, and upload the signal to the receiving end optical module; the receiving end optical module is used to detect, correct and split the received signal, and upload the signal to the receiving end signal detection module; the receiving end signal detection module is used to generate local local oscillator light, and perform coherent mixing and homodyne detection on the local oscillator light and the received signal, and upload the signal to the receiving end data acquisition module; the receiving end data acquisition module is used to receive the signal. In the specific implementation, the data acquisition module at the receiving end is an FPGA data acquisition card of model ADS8-V1EBZ, two of which are required, and the sampling rate of each card is above 10GSa / s.

[0033] like Figure 4The figure shows a functional module diagram of a receiving end piezoelectric fast steering mirror module of a quantum key receiving end of the system of the present invention: the receiving end piezoelectric fast steering mirror module comprises a steering mirror four-phase controller, a steering mirror FSM controller, a steering mirror FSM reflector and a steering mirror beam splitter; the output end of the steering mirror four-phase controller, the steering mirror FSM controller, the steering mirror FSM reflector and the input end of the steering mirror beam splitter are connected in series in sequence; the first input end of the steering mirror four-phase controller is connected to a receiving end collimator, the second input end of the steering mirror four-phase controller is connected to a first output end of the steering mirror beam splitter, and the second output end of the steering mirror beam splitter is connected to a receiving end optical module; the steering mirror four-phase controller The controller is used to receive the light beam signal uploaded by the collimator at the receiving end, measure the elevation and azimuth of the light beam as feedback signals, and send them to the steering mirror FSM controller; the steering mirror FSM controller is used to read the signal, send down the control signal to control the FSM reflector, and also forward the light beam signal to the steering mirror FSM reflector; the steering mirror FSM reflector is used to adjust the reflection angle, correct the received light beam, and send the corrected light beam to the self-steering mirror beam splitter; the steering mirror beam splitter is used to divide the received light beam into two paths, and the 1% light beam is used for feedback control by the steering mirror four-phase controller; the 99% light beam is sent to the receiving end optical module.

[0034] like Figure 5 The figure shows a functional module diagram of the receiving end optical module of the quantum key receiving end of the system of the present invention: the receiving end optical module includes an optical module wavefront sensor, an optical module wavefront controller, an optical module wavefront corrector and an optical module beam splitter; the input ends of the optical module wavefront sensor, the optical module wavefront controller, the optical module wavefront corrector and the optical module beam splitter are connected in series in sequence; the first output end of the optical module beam splitter is connected to the optical module wavefront controller, and the second output end of the optical module beam splitter is connected to the receiving end signal detection module; the optical module wavefront sensor is used to receive signals and measure the wavefront aberration of the light beam. As a feedback signal, it is sent to the optical module wavefront controller; the optical module wavefront controller is used to control the optical module wavefront corrector according to the feedback signal uploaded by the optical module beam splitter, and also forwards the light beam signal to the optical module wavefront corrector; the optical module wavefront corrector is used to perform wavefront correction on the received light beam signal, and send the corrected signal to the optical module beam splitter; the optical module beam splitter is used to divide the received light beam signal into two paths, 1% of the light beam signal is uploaded to the optical module wavefront controller as a feedback signal, and 99% of the light beam signal is uploaded to the receiving end signal detection module.

[0035] like Figure 6The figure shows a functional module diagram of a receiving-end signal detection module of a quantum key receiving end of the system of the present invention: the receiving-end signal detection module comprises a first polarization controller for signal detection, a 90° optical mixer for signal detection, a local oscillator for signal detection, a second polarization controller for signal detection and a homodyne detector for signal detection; the output end of the first polarization controller for signal detection is connected to the first input end of the 90° optical mixer for signal detection; the local oscillator for signal detection and the second polarization controller for signal detection are connected in series; the output end of the second polarization controller for signal detection is connected to the second input end of the 90° optical mixer for signal detection; the output end of the 90° optical mixer for signal detection is connected to the input end of the homodyne detector for signal detection, and the output end of the homodyne detector for signal detection is connected to the receiving-end data acquisition Module; the first polarization controller of signal detection is used to receive the polarization of the signal light beam uploaded by the optical module at the receiving end, correct it, and send the corrected signal light beam to the 90° optical mixer of signal detection; the local oscillator of signal detection is used to generate a local local oscillator light signal, and upload it to the second polarization controller of signal detection; the second polarization controller of signal detection is used to receive the local local oscillator light signal, and send the local oscillator light signal to the 90° optical mixer of signal detection after polarization correction; the 90° optical mixer of signal detection is used to mix the received local oscillator light and the signal light, and send the mixed signal to the homodyne detector of signal detection; the homodyne detector of signal detection is used to perform homodyne detection on the received signal, and upload the detection result to the data acquisition module at the receiving end. In the specific implementation, the homodyne detector of signal detection is a balanced amplified photoelectric detector of model Optilab EPR-23-M, with a common mode rejection ratio greater than 40Db and a bandwidth of up to 23GHz.

[0036] like Figure 7 The method flow diagram of the method of the present invention is shown as follows: the distribution method of the ocean turbulence channel quantum key distribution system provided by the present invention specifically comprises the following steps:

[0037] S1. The quantum signal transmitter generates an optical pulse and a modulation signal, performs QPSK and Gaussian modulation on the optical pulse according to the generated modulation signal, decays the modulated signal to the expected coherent state, and sends it to the quantum signal receiver through the quantum channel;

[0038] S2. After receiving the signal, the quantum signal receiving end measures the elevation and azimuth angles of the light beam through the piezoelectric fast steering mirror module at the receiving end, and corrects the light beam;

[0039] S3. The quantum signal receiving end performs wavefront correction on the corrected light beam again through the receiving end optical module to obtain a signal light beam;

[0040] S4. The quantum signal receiving end generates a local light beam, and after coherent mixing and homodyne detection with the signal beam obtained in step S3, the detection result is collected for data;

[0041] S5. Based on the collected signal, the quantum key receiver conducts key negotiation and private amplification with the quantum key sender, and finally completes the distribution of the quantum key.

Claims

1. A quantum key distribution system for ocean turbulence channels, characterized in that It includes a quantum key transmitter and a quantum key receiver; both the quantum key transmitter and the quantum key receiver are arranged in an ocean turbulent channel; The quantum key transmitter is used to modulate the classical signal, and after superimposing the modulated classical signal on the quantum signal, it is sent to the quantum key receiver through the quantum channel; the quantum key receiver is used to realize real-time detection of the distorted wavefront, correct the wavefront distortion caused by high-order wavefront aberrations, and realize key negotiation and private amplification with the quantum key transmitter through subsequent detection, thereby completing the distribution of quantum keys; The quantum key receiving end comprises a receiving end collimator, a receiving end piezoelectric fast steering mirror module, a receiving end optical module, a receiving end signal detection module and a receiving end data acquisition module; the receiving end collimator, the receiving end piezoelectric fast steering mirror module, the receiving end optical module, the receiving end signal detection module and the receiving end data acquisition module are connected in series in sequence; the receiving end collimator is used to receive the signal sent by the quantum signal sending end through the quantum channel, and upload it to the receiving end piezoelectric fast steering mirror module; the receiving end piezoelectric fast steering mirror module is used to measure, feedback and split the received signal, and upload the signal to the receiving end optical module; The receiving end optical module is used to detect, correct and split the received signal, and upload the signal to the receiving end signal detection module; the receiving end signal detection module is used to generate local oscillator light, and perform coherent mixing and homodyne detection on the local oscillator light and the received signal, and upload the signal to the receiving end data acquisition module; the receiving end data acquisition module is used to receive the signal; The receiving end piezoelectric fast steering mirror module comprises a steering mirror four-phase controller, a steering mirror FSM controller, a steering mirror FSM reflector and a steering mirror beam splitter; the output end of the steering mirror four-phase controller, the steering mirror FSM controller, the steering mirror FSM reflector and the input end of the steering mirror beam splitter are connected in series in sequence; the first input end of the steering mirror four-phase controller is connected to the receiving end collimator, the second input end of the steering mirror four-phase controller is connected to the first output end of the steering mirror beam splitter, and the second output end of the steering mirror beam splitter is connected to the receiving end optical module; the steering mirror four-phase controller is used to receive the light beam uploaded by the receiving end collimator The signal is measured, and the elevation and azimuth angles of the light beam are measured as feedback signals, and sent to the steering mirror FSM controller; the steering mirror FSM controller is used to read the signal, send a control signal to control the FSM reflector, and also forward the light beam signal to the steering mirror FSM reflector; the steering mirror FSM reflector is used to adjust the reflection angle, correct the received light beam, and send the corrected light beam to the self-steering mirror beam splitter; the steering mirror beam splitter is used to split the received light beam into two paths, and the 1% light beam is used for feedback control by the steering mirror four-phase controller; the 99% light beam is sent to the receiving end optical module; The receiving end optical module comprises an optical module wavefront sensor, an optical module wavefront controller, an optical module wavefront corrector and an optical module beam splitter; the input ends of the optical module wavefront sensor, the optical module wavefront controller, the optical module wavefront corrector and the optical module beam splitter are connected in series in sequence; the first output end of the optical module beam splitter is connected to the optical module wavefront controller, and the second output end of the optical module beam splitter is connected to the receiving end signal detection module; the optical module wavefront sensor is used to receive signals, measure the wavefront aberration of the light beam as a feedback signal, and send it to the optical module wavefront controller; the optical module wavefront controller is used to control the optical module wavefront corrector according to the feedback signal uploaded by the optical module beam splitter, and also forward the light beam signal to the optical module wavefront corrector; the optical module wavefront corrector is used to perform wavefront correction on the received light beam signal, and send the corrected signal to the optical module beam splitter; the optical module beam splitter is used to divide the received light beam signal into two paths, 1% of the light beam signal is uploaded to the optical module wavefront controller as a feedback signal, and 99% of the light beam signal is uploaded to the receiving end signal detection module.

2. The ocean turbulence channel quantum key distribution system according to claim 1, characterized in that The quantum key transmitter comprises a transmitter pulse laser, a transmitter signal generation module, a transmitter electro-optical phase modulation and amplitude modulator, a transmitter variable optical attenuator and a transmitter collimator; the transmitter pulse laser, the transmitter electro-optical phase modulation and amplitude modulator, the transmitter variable optical attenuator and the transmitter collimator are sequentially connected in series, and the output end of the transmitter signal generation module is connected to the input end of the transmitter electro-optical phase modulation and amplitude modulator; the transmitter pulse laser is used to generate optical pulses, and the generated optical pulses are sent to the transmitter electro-optical phase modulation and amplitude modulator; The signal generation module at the transmitting end is used to generate an analog signal that obeys the Rayleigh distribution and an analog signal with QPSK superimposed uniform distribution, and send them to the electro-optical phase modulation and amplitude modulator at the transmitting end, wherein the analog signal that obeys the Rayleigh distribution is used to modulate the light field intensity, and the analog signal with QPSK superimposed uniform distribution is used to modulate the light field phase; the electro-optical phase modulation and amplitude modulator at the transmitting end is used to simultaneously perform QPSK and Gaussian modulation on the received optical pulses, and send the modulated signal to the variable optical attenuator at the transmitting end; The variable optical attenuator at the transmitting end is used to attenuate the energy of the received signal light to the expected coherent state and send it to the transmitting end collimator; the transmitting end collimator is used to send the received optical signal to the quantum key receiving end through the quantum channel.

3. The ocean turbulence channel quantum key distribution system according to claim 2, characterized in that The transmitting end electro-optical phase modulation and amplitude modulator includes a transmitting end electro-optical phase modulator and a transmitting end amplitude modulator. The transmitting end electro-optical phase modulator is an electro-optical phase modulator of model MPZ-LN-10, and the transmitting end amplitude modulator is an amplitude modulator of model MX-LN-10; the transmitting end pulse laser is a picosecond optical pulse generator of model OPG1015; and the transmitting end signal generation module is an FPGA signal generation card of model Xilinx VC707.

4. The ocean turbulence channel quantum key distribution system according to claim 1, characterized in that The receiving end signal detection module comprises a first polarization controller for signal detection, a 90° optical mixer for signal detection, a local oscillator for signal detection, a second polarization controller for signal detection and a homodyne detector for signal detection; the output end of the first polarization controller for signal detection is connected to the first input end of the 90° optical mixer for signal detection; the local oscillator for signal detection and the second polarization controller for signal detection are connected in series; the output end of the second polarization controller for signal detection is connected to the second input end of the 90° optical mixer for signal detection; the output end of the 90° optical mixer for signal detection is connected to the input end of the homodyne detector for signal detection, and the output end of the homodyne detector for signal detection is connected to Data acquisition module at the receiving end; the first polarization controller of the signal detection is used to receive the polarization of the signal light beam uploaded by the optical module at the receiving end, correct it, and send the corrected signal light beam to the 90° optical mixer of the signal detection; the local oscillator of the signal detection is used to generate a local local oscillator light signal, and upload it to the second polarization controller of the signal detection; the second polarization controller of the signal detection is used to receive the local local oscillator light signal, and send the local oscillator light signal to the 90° optical mixer of the signal detection after polarization correction; the 90° optical mixer of the signal detection is used to mix the received local oscillator light and the signal light, and send the mixed signal to the homodyne detector of the signal detection; The signal detection homodyne detector is used to perform homodyne detection on the received signal and upload the detection result to the receiving end data acquisition module.

5. The ocean turbulence channel quantum key distribution system according to claim 4, characterized in that The receiving end data acquisition module is an FPGA data acquisition card with the model number ADS8-V1EBZ; the signal detection homodyne detector is a balanced amplified photoelectric detector with the model number Optilab EPR-23-M.

6. A distribution method of the ocean turbulent channel quantum key distribution system according to any one of claims 1 to 5, characterized in that The specific steps include: S1. The quantum signal transmitter generates an optical pulse and a modulation signal, performs QPSK and Gaussian modulation on the optical pulse according to the generated modulation signal, decays the modulated signal to the expected coherent state, and sends it to the quantum signal receiver through the quantum channel; S2. After receiving the signal, the quantum signal receiving end measures the elevation and azimuth angles of the light beam through the piezoelectric fast steering mirror module at the receiving end, and corrects the light beam; S3. The quantum signal receiving end performs wavefront correction on the corrected light beam again through the receiving end optical module to obtain a signal light beam; S4. The quantum signal receiving end generates a local light beam, and after coherent mixing and homodyne detection with the signal beam obtained in step S3, the detection result is collected for data; S5. Based on the collected signal, the quantum key receiver conducts key negotiation and private amplification with the quantum key sender, and finally completes the distribution of the quantum key.

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