CN113411136B - A quadrature modulation secure optical communication device and method - Google Patents

Abstract

The present invention provides a quadrature modulation secure optical communication device and method. The device includes a pulse light source generator, a signal modulation module, a time-domain phase encoding module, a transmission fiber, a time-domain phase decoding module, a demodulation module and an operator, wherein: The output end of the pulse light source generator is connected with the input end of the signal modulation module. The signal modulation module modulates the phase and intensity of the optical signal sent by the pulse light source generator at the same time. The output end of the signal modulation module is connected to the input end of the time domain phase encoding module. connection, the time domain phase encoding module encodes the modulated optical signal, the output end of the time domain phase encoding module is connected with the input end of the transmission fiber, the output end of the transmission fiber is connected with the input end of the time domain phase decoding module, the time domain The output end of the phase decoding module is respectively connected with the input end of the demodulation module and the input end of the operator, the output end of the demodulation module outputs the demodulated signal, and the output end of the operator outputs the original signal strength information.

Description

A quadrature modulation secure optical communication device and method

technical field

The present invention relates to the technical field of safe optical security communication, and more particularly, relates to an orthogonal modulation security optical communication device and method.

Background technique

With the rapid development of modern communication technology, how to improve the security transmission performance of the physical layer of the communication system has received extensive attention. The purpose of secure communication at the physical layer is to reduce the risk of information being eavesdropped. The process of secure communication mainly includes encryption, transmission, reception, and decryption. The sender encrypts and transmits the information to be transmitted, and the transmitted encrypted information is received and decrypted at the receiving end, and finally restores the original information. Information will inevitably be stolen, attacked and forged by illegal eavesdroppers during transmission. It is very unfavorable to the legal receiver, so how to effectively improve the system security performance is a problem that must be considered by both parties in communication.

Optical Code Division Multiple Access (OCDMA) is a broadband optical access network solution, using ultra-short pulse coherent optical code division multiple access (OCDMA) technology with low multiple access interference, strong anti-interference ability, good confidentiality performance, and capacity Large and other advantages, it has become an alternative technology for secure optical communication. In a coherent OCDMA system, coherent optical encoding and decoding is based on the phase and amplitude of the light field. In a typical OCDMA system, the optical pulse is encoded into a noise-like signal according to the unique optical code assigned to different users by the optical encoder on the transmitter, and multiple users can share the same transmission medium, such as time and spectrum. In order to improve the security performance of optical coding and decoding systems, a large number of technical methods focus on the time domain or frequency domain to process the optical phase of coherent broadband optical signals. The proposed coding/decoding devices include: superstructured fiber Bragg gratings, planar lightwave circuits, microring resonator etc. These traditional optical encoders/decoders usually have fixed codewords and limited code lengths. At the same time, they cannot provide fast reconfigurable capabilities and are difficult to meet the needs of secure communication. In addition, traditional optical codec security communication systems only use basic modulation formats such as amplitude keying, frequency shift keying, and phase shift keying for data modulation. The spectral efficiency of the system is low, and the security performance of the system is closely related to the modulation format. . For a single modulation format, optical encoding through traditional optical codec devices cannot guarantee the security performance of the system.

The publication date is August 15, 2017, and the Chinese patent with the publication number CN107046463A discloses a chaotic security communication system based on a microring resonator, including a laser, which is sequentially connected by an optical filter, an isolator, and a polarization controller. The first port of the splitter, the splitter divides the continuous wave into two paths, the first path: the second port of the splitter passes through the first microring resonator, the multiplexer, the first erbium-doped fiber amplifier, the first PD The detector is connected to the first port of the differential amplifier; the weak information enters the combiner and is combined with the chaotic signal from the first microring resonator; the second way: the third port of the splitter passes through the second microring resonator, The second erbium-doped fiber amplifier and the second PD detector are connected to the second port of the differential amplifier; signals from the first PD detector and the second PD detector enter the differential amplifier, and the information is restored after subtraction, and the third port of the differential amplifier is connected to the differential amplifier. The first port of the electric filter is connected, and the information recovered after subtracting the two paths into the differential amplifier is output from the second port of the electric filter. This patent also fails to provide fast reconfigurable capabilities, and is difficult to meet the needs of secure communication.

Contents of the invention

The primary purpose of the present invention is to provide a quadrature modulation secure optical communication device, which solves the problems that the traditional optical encoder/decoder cannot be reconfigured quickly, and the system security and spectrum efficiency are low, and improves the system spectrum efficiency while ensuring security .

The secondary purpose of the present invention is to provide a quadrature modulation secure optical communication method.

In order to solve the problems of the technologies described above, the technical solution of the present invention is as follows:

A quadrature modulation secure optical communication device, comprising a pulse light source generator, a signal modulation module, a time-domain phase encoding module, a transmission fiber, a time-domain phase decoding module, a demodulation module and an arithmetic unit, wherein:

The output end of the pulse light source generator is connected to the input end of the signal modulation module, and the signal modulation module simultaneously performs phase and intensity modulation on the optical signal sent by the pulse light source generator, and the output of the signal modulation module connected to the input end of the time-domain phase encoding module, the time-domain phase encoding module encodes the modulated optical signal, the output end of the time-domain phase encoding module is connected to the input end of the transmission fiber, and the The output end of the transmission fiber is connected to the input end of the time domain phase decoding module, the output end of the time domain phase decoding module is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit, and the input end of the demodulation module The output end outputs the demodulated signal, and the output end of the arithmetic unit outputs original signal strength information.

Preferably, the signal modulation module includes a QPSK modulator and a CSK modulator, wherein the output end of the pulse light source generator is connected to the input end of the QPSK modulator, and the QPSK modulator generates The optical signal sent by the QPSK modulator is QPSK modulated, the output end of the QPSK modulator is connected to the input end of the CSK modulator, and the CSK modulator performs CSK modulation on the QPSK modulated optical signal, and the CSK modulator It has two output terminals, the time-domain phase encoding module has two input terminals, and the two output terminals of the CSK modulator are connected to the two input terminals of the time-domain phase encoding module.

Preferably, the demodulation module includes a QPSK demodulator, wherein the output terminal of the time-domain phase decoding module is connected to the input terminal of the QPSK demodulator, and the QPSK demodulator performs QPSK demodulation on the optical signal, so The output terminal of the QPSK demodulator outputs the optical signal after QPSK demodulation.

Preferably, the time-domain phase encoding module includes a first single-mode fiber, a second single-mode fiber, a third single-mode fiber, a fourth single-mode fiber, a first phase modulator, a second phase modulator, a first PRBS generator and a second PRBS generator, where:

The input end of the first single-mode optical fiber is connected to an output end of the CSK modulator, the output end of the first single-mode optical fiber is connected to an input end of the first phase modulator, and the first The other input end of the phase modulator is connected to the output end of the first PRBS generator, and the first PRBS generator generates a first drive signal to drive the first phase modulator to generate a random optical phase, and the first phase modulator The output end of the device is connected to the input end of the second single-mode optical fiber, and the output end of the second single-mode optical fiber is connected to the transmission optical fiber;

The input end of the third single-mode optical fiber is connected to the other output end of the CSK modulator, the output end of the third single-mode optical fiber is connected to an input end of the second phase modulator, and the first The other input end of the two-phase modulator is connected to the output end of the second PRBS generator, and the second PRBS generator generates a second driving signal to drive the second phase modulator to generate a random optical phase, and the second phase The output end of the modulator is connected to the input end of the fourth single-mode optical fiber, and the output end of the fourth single-mode optical fiber is connected to the transmission optical fiber.

Preferably, it also includes a first optical coupler and a first beam splitter, the output end of the second single-mode fiber and the output end of the fourth single-mode fiber are coupled to the transmission through the first optical coupler An optical fiber, the time-domain phase decoding module has two input ends, the output end of the transmission fiber is decomposed into two beams of optical signals by the first beam splitter, and respectively input to the two input ends of the time-domain phase decoding module end.

Preferably, the time-domain phase decoding module includes a fifth single-mode fiber, a sixth single-mode fiber, a seventh single-mode fiber, an eighth single-mode fiber, a third phase modulator, a fourth phase modulator, a third PRBS generator and a fourth PRBS generator, wherein:

The input end of the fifth single-mode optical fiber inputs a bundle of optical signals decomposed by the first beam splitter, and the output end of the fifth single-mode optical fiber is connected to an input end of the third phase modulator, The other input end of the third phase modulator is connected to the output end of the third PRBS generator, the third PRBS generator generates a third drive signal to drive the third phase modulator to generate a random optical phase, the The output end of the third phase modulator is connected to the input end of the sixth single-mode optical fiber, and the output end of the sixth single-mode optical fiber is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit;

The input end of the seventh single-mode fiber inputs another beam of optical signals decomposed by the first beam splitter, and the output end of the seventh single-mode fiber is connected to an input end of the fourth phase modulator , the other input end of the fourth phase modulator is connected to the output end of the fourth PRBS generator, and the fourth PRBS generator generates a fourth drive signal to drive the fourth phase modulator to generate a random optical phase, so The output end of the fourth phase modulator is connected to the input end of the eighth single-mode optical fiber, and the output end of the eighth single-mode optical fiber is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit.

Preferably, it also includes a second beam splitter, a third beam splitter, a second optical coupler, a first photodetector and a second photodetector, the output end of the sixth single-mode fiber passes through the second The beam splitter is divided into two beams of optical signals, and the output end of the eighth single-mode optical fiber is divided into two beams of optical signals by the third beam splitter, and one beam of optical signals output by the second beam splitter is connected to the eighth optical signal. One of the optical signals output by the single-mode optical fiber is input to the demodulation module through the second optical coupler, and the input end of the first photodetector is input to the other optical signal split by the second beam splitter. An optical signal, the output end of the first photodetector is connected to the non-inverting input end of the operator, and the input end of the second photodetector inputs another optical signal decomposed by the third beam splitter , the output end of the second photodetector is connected to the inverting input end of the arithmetic unit.

Preferably, the first single-mode fiber, the third single-mode fiber, the fifth single-mode fiber and the seventh single-mode fiber are positive dispersion single-mode fibers, and the second single-mode fiber, the fourth single-mode fiber, the The six single-mode fibers and the eighth single-mode fiber are anti-dispersion single-mode fibers.

Preferably, an optical amplifier is also included, and the optical amplifier is arranged on the transmission way of the transmission optical fiber, and is used for amplifying the optical signal in the transmission optical fiber.

A quadrature modulation secure optical communication method, the method is applied to the above-mentioned quadrature modulation secure optical communication device, comprising the following steps:

The optical pulse generated by the pulse light source generator 101 is input to the QPSK modulator 201 to generate a quadrature phase shift keying optical signal, and the optical signal is input to the CSK modulator 301 to load intensity information, and the two outputs of the CSK modulator 301 are respectively connected to to the two input ends of the time-domain phase encoding module 4, then the signal encrypted by phase encoding is coupled into the transmission fiber through the first optical coupler 501, and the optical amplifier 601 is used in the transmission fiber to amplify the attenuated optical signal, and then through The first beam splitter 701 enters the time-domain phase decoding module 8 for releasing the random optical phase, the output of the time-domain phase decoding module 8 passes through two beam splitters respectively, and one output of the beam splitter is used to demodulate the QPSK signal, All the way through the balance detector detection, the original intensity information is obtained through the operation of the calculator.

Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

The present invention utilizes the modulation module to simultaneously perform phase and intensity modulation on optical information, which increases a modulation dimension compared with a single modulation dimension and improves system transmission capability. Using the time-domain phase encoding module, the spectral phase encoding is realized by applying different phase offsets to different spectral components of the ultrashort optical pulse, and the modulated signal is encrypted, which effectively improves the security performance of the system and can be carried information transfer rate.

Description of drawings

Figure 1 is a schematic diagram of the device of the present invention.

In the figure, 101 is a pulse light source generator, 201 is a QPSK modulator, 301 is a CSK modulator, 4 is a time-domain phase encoding module, 401 is the first single-mode fiber, 402 is the third single-mode fiber, 403 is the first Phase modulator, 404 is the second phase modulator, 405 is the second single-mode fiber, 406 is the fourth single-mode fiber, 407 is the first PRBS generator, 408 is the second PRBS generator, 501 is the first optical coupling 601 is an optical amplifier, 701 is a first beam splitter, 8 is a time-domain phase decoding module, 801 is a fifth single-mode fiber, 802 is a seventh single-mode fiber, 803 is a third phase modulator, 804 is a first Four-phase modulator, 805 is the sixth single-mode fiber, 806 is the eighth single-mode fiber, 807 is the third PRBS generator, 808 is the fourth PRBS generator, 901 is the second beam splitter, 1001 is the third splitter 1101 is a second optical coupler, 1201 is a QPSK demodulator, 1301 is a first photodetector, 1401 is a second photodetector, 1501 is an arithmetic unit.

Detailed ways

The accompanying drawings are for illustrative purposes only and cannot be construed as limiting the patent;

In order to better illustrate this embodiment, some parts in the drawings will be omitted, enlarged or reduced, and do not represent the size of the actual product;

For those skilled in the art, it is understandable that some well-known structures and descriptions thereof may be omitted in the drawings.

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Example 1

This embodiment provides a quadrature modulation secure optical communication device, as shown in FIG. Module and arithmetic unit 1501, wherein:

The output end of the pulse light source generator 101 is connected to the input end of the signal modulation module, and the signal modulation module simultaneously performs phase and intensity modulation on the optical signal sent by the pulse light source generator 101, and the signal modulation module The output end of the time domain phase encoding module 4 is connected to the input end of the time domain phase encoding module 4, and the modulated optical signal is encoded by the time domain phase encoding module 4, and the output end of the time domain phase encoding module 4 is connected to the input of the transmission optical fiber The output end of the transmission fiber is connected to the input end of the time domain phase decoding module 8, and the output end of the time domain phase decoding module 8 is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit 1501 connected, the output terminal of the demodulation module outputs the demodulated signal, and the output terminal of the arithmetic unit 1501 outputs the original signal strength information.

The signal modulation module includes a QPSK modulator 201 and a CSK modulator 301, wherein the output end of the pulse light source generator 101 is connected to the input end of the QPSK modulator 201, and the QPSK modulator 201 controls the pulse The optical signal sent by the light source generator 101 is subjected to QPSK modulation, the output end of the QPSK modulator 201 is connected to the input end of the CSK modulator 301, and the CSK modulator 301 performs CSK modulation on the QPSK modulated optical signal , the CSK modulator 301 has two output terminals, the time domain phase encoding module 4 has two input terminals, the two output terminals of the CSK modulator 301 are connected to the two output terminals of the time domain phase encoding module 4 input connection.

The demodulation module includes a QPSK demodulator 1201, wherein the output terminal of the time-domain phase decoding module 8 is connected to the input terminal of the QPSK demodulator 1201, and the QPSK demodulator 1201 performs QPSK demodulation on the optical signal, The output terminal of the QPSK demodulator 1201 outputs the QPSK demodulated optical signal.

The time-domain phase encoding module 4 includes a first single-mode fiber 401, a second single-mode fiber 405, a third single-mode fiber 402, a fourth single-mode fiber 406, a first phase modulator 403, and a second phase modulator 404 , the first PRBS generator 407 and the second PRBS generator 408, wherein:

The input end of the first single-mode optical fiber 401 is connected to an output end of the CSK modulator 301, and the output end of the first single-mode optical fiber 401 is connected to an input end of the first phase modulator 403, The other input end of the first phase modulator 403 is connected to the output end of the first PRBS generator 407, and the first PRBS generator 407 generates a first driving signal to drive the first phase modulator 403 to generate random light phase, the output end of the first phase modulator 403 is connected to the input end of the second single-mode optical fiber 405, and the output end of the second single-mode optical fiber 405 is connected to the transmission optical fiber;

The input end of the third single-mode optical fiber 402 is connected to the other output end of the CSK modulator 301, and the output end of the third single-mode optical fiber 402 is connected to an input end of the second phase modulator 404 , the other input end of the second phase modulator 404 is connected to the output end of the second PRBS generator 408, and the second PRBS generator 408 generates a second driving signal to drive the second phase modulator 404 to generate random Optical phase, the output end of the second phase modulator 404 is connected to the input end of the fourth single-mode optical fiber 406, and the output end of the fourth single-mode optical fiber 406 is connected to the transmission optical fiber.

Also includes a first optical coupler 501 and a first beam splitter 701, the output end of the second single-mode optical fiber 405 and the output end of the fourth single-mode optical fiber 406 are coupled to the The transmission optical fiber, the time-domain phase decoding module 8 has two input ends, the output end of the transmission optical fiber is decomposed into two beams of optical signals by the first beam splitter 701, and input to the time-domain phase decoding module respectively 8's two inputs.

The time-domain phase decoding module 8 includes a fifth single-mode fiber 801, a sixth single-mode fiber 805, a seventh single-mode fiber 802, an eighth single-mode fiber 806, a third phase modulator 803, and a fourth phase modulator 804 , the third PRBS generator 807 and the fourth PRBS generator 808, wherein:

The input end of the fifth single-mode optical fiber 801 inputs a bundle of optical signals decomposed by the first beam splitter 701, and the output end of the fifth single-mode optical fiber 801 is connected to one of the third phase modulators 803 The input end is connected, the other input end of the third phase modulator 803 is connected to the output end of the third PRBS generator 807, and the third PRBS generator 807 generates a third driving signal to drive the third phase modulator 803 generates a random optical phase, the output end of the third phase modulator 803 is connected to the input end of the sixth single-mode optical fiber 805, and the output end of the sixth single-mode optical fiber 805 is respectively connected to the demodulation module The input end is connected to the input end of the arithmetic unit 1501;

The input end of the seventh single-mode optical fiber 802 inputs another beam of optical signals decomposed by the first beam splitter 701, and the output end of the seventh single-mode optical fiber 802 is connected to the fourth phase modulator 804 One input terminal is connected, the other input terminal of the fourth phase modulator 804 is connected to the output terminal of the fourth PRBS generator 808, and the fourth PRBS generator 808 generates a fourth driving signal to drive the fourth phase modulation A random optical phase is generated by a device 804, the output end of the fourth phase modulator 804 is connected to the input end of the eighth single-mode optical fiber 806, and the output end of the eighth single-mode optical fiber 806 is respectively connected to the demodulation module The input terminal of is connected with the input terminal of the arithmetic unit 1501.

It also includes a second beam splitter 901, a third beam splitter 1001, a second optical coupler 1101, a first photodetector 1301 and a second photodetector 1401, the output end of the sixth single-mode fiber 805 passes through the The second beam splitter 901 is divided into two beams of optical signals, the output end of the eighth single-mode fiber 806 is divided into two beams of optical signals by the third beam splitter 1001, and the output of the second beam splitter 901 is A beam of optical signals and one of the beams of optical signals output by the eighth single-mode optical fiber 806 are input to the demodulation module through the second optical coupler 1101, and the input terminal of the first photodetector 1301 is input through the Another beam of optical signals decomposed by the second beam splitter 901, the output end of the first photodetector 1301 is connected to the non-inverting input end of the arithmetic unit 1501, and the input end of the second photodetector 1401 is input via For another optical signal split by the third beam splitter 1001 , the output end of the second photodetector 1401 is connected to the inverting input end of the arithmetic unit 1501 .

The first single-mode optical fiber 401, the third single-mode optical fiber 402, the fifth single-mode optical fiber 801 and the seventh single-mode optical fiber 802 are positive dispersion single-mode optical fibers, and the positive dispersion single-mode optical fiber is used to stretch the pulse in the time domain, and then Different spectral components of the input pulse will be extended to different time positions within a bit duration, and the second single-mode fiber 405, the fourth single-mode fiber 406, the sixth single-mode fiber 805 and the eighth single-mode fiber 806 are Anti-dispersion single-mode fiber, anti-dispersion single-mode fiber performs time-domain compression on the stretched pulse, and finally achieves the purpose of phase encoding encryption.

An optical amplifier 601 is also included, and the optical amplifier 601 is arranged on the transmission route of the transmission optical fiber, and is used for amplifying the optical signal in the transmission optical fiber.

Example 2

This embodiment provides a quadrature modulation secure optical communication method, the method is applied to the quadrature modulation secure optical communication device described in Embodiment 1, including the following steps:

The optical pulse generated by the pulse light source generator 101 is input to the QPSK modulator 201 to generate a quadrature phase shift keying optical signal, and the optical signal is input to the CSK modulator 301 to load intensity information, and the two outputs of the CSK modulator 301 are respectively connected to to the two input ends of the time-domain phase encoding module 4, then the signal encrypted by phase encoding is coupled into the transmission fiber through the first optical coupler 501, and the optical amplifier 601 is used in the transmission fiber to amplify the attenuated optical signal, and then through The first beam splitter 701 enters the time-domain phase decoding module 8 for releasing the random optical phase, the output of the time-domain phase decoding module 8 passes through two beam splitters respectively, and one output of the beam splitter is used to demodulate the QPSK signal, All the way through the balance detector detection, the original intensity information is obtained through the operation of the calculator.

The same or similar reference numerals correspond to the same or similar components;

The terms describing the positional relationship in the drawings are only for illustrative purposes and cannot be interpreted as limitations on this patent;

Apparently, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the implementation of the present invention. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. All modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the claims of the present invention.

Claims (9)

1. A quadrature modulation secure optical communication device, characterized in that it comprises a pulsed light source generator, a signal modulation module, a time-domain phase encoding module, a transmission fiber, a time-domain phase decoding module, a demodulation module and an arithmetic unit, wherein: The output end of the pulse light source generator is connected to the input end of the signal modulation module, and the signal modulation module simultaneously performs phase and intensity modulation on the optical signal sent by the pulse light source generator, and the output of the signal modulation module connected to the input end of the time-domain phase encoding module, the time-domain phase encoding module encodes the modulated optical signal, the output end of the time-domain phase encoding module is connected to the input end of the transmission fiber, and the The output end of the transmission fiber is connected to the input end of the time domain phase decoding module, the output end of the time domain phase decoding module is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit, and the input end of the demodulation module The output terminal outputs a demodulated signal, and the output terminal of the arithmetic unit outputs original signal strength information; The signal modulation module includes a QPSK modulator and a CSK modulator, wherein the output end of the pulse light source generator is connected to the input end of the QPSK modulator, and the QPSK modulator sends the pulsed light source generator The optical signal is QPSK modulated, the output end of the QPSK modulator is connected to the input end of the CSK modulator, and the CSK modulator performs CSK modulation on the QPSK modulated optical signal, and the CSK modulator has two Output terminal, the time-domain phase encoding module has two input terminals, and the two output terminals of the CSK modulator are connected to the two input terminals of the time-domain phase encoding module. 2. The quadrature modulation secure optical communication device according to claim 1, wherein the demodulation module comprises a QPSK demodulator, wherein the output terminal of the time-domain phase decoding module is connected to the input of the QPSK demodulator The terminals are connected, the QPSK demodulator performs QPSK demodulation on the optical signal, and the output terminal of the QPSK demodulator outputs the QPSK demodulated optical signal. 3. The quadrature modulation security optical communication device according to claim 1, wherein the time-domain phase encoding module comprises a first single-mode optical fiber, a second single-mode optical fiber, a third single-mode optical fiber, a fourth single-mode optical fiber, and a second single-mode optical fiber. mode fiber, a first phase modulator, a second phase modulator, a first PRBS generator and a second PRBS generator, wherein: The input end of the first single-mode optical fiber is connected to an output end of the CSK modulator, the output end of the first single-mode optical fiber is connected to an input end of the first phase modulator, and the first The other input end of the phase modulator is connected to the output end of the first PRBS generator, and the first PRBS generator generates a first drive signal to drive the first phase modulator to generate a random optical phase, and the first phase modulator The output end of the device is connected to the input end of the second single-mode optical fiber, and the output end of the second single-mode optical fiber is connected to the transmission optical fiber; The input end of the third single-mode optical fiber is connected to the other output end of the CSK modulator, the output end of the third single-mode optical fiber is connected to an input end of the second phase modulator, and the first The other input end of the two-phase modulator is connected to the output end of the second PRBS generator, and the second PRBS generator generates a second driving signal to drive the second phase modulator to generate a random optical phase, and the second phase The output end of the modulator is connected to the input end of the fourth single-mode optical fiber, and the output end of the fourth single-mode optical fiber is connected to the transmission optical fiber. 4. The quadrature modulation security optical communication device according to claim 3, further comprising a first optical coupler and a first beam splitter, the output end of the second single-mode optical fiber and the fourth single-mode optical fiber The output end of the optical fiber is coupled to the transmission optical fiber through the first optical coupler, the time-domain phase decoding module has two input ends, and the output end of the transmission optical fiber is decomposed into Two beams of optical signals are respectively input to two input terminals of the time-domain phase decoding module. 5. The quadrature modulation secure optical communication device according to claim 4, wherein the time-domain phase decoding module includes a fifth single-mode optical fiber, a sixth single-mode optical fiber, a seventh single-mode optical fiber, an eighth single-mode optical fiber mode fiber, a third phase modulator, a fourth phase modulator, a third PRBS generator and a fourth PRBS generator, wherein: The input end of the fifth single-mode optical fiber inputs a bundle of optical signals decomposed by the first beam splitter, and the output end of the fifth single-mode optical fiber is connected to an input end of the third phase modulator, The other input end of the third phase modulator is connected to the output end of the third PRBS generator, the third PRBS generator generates a third drive signal to drive the third phase modulator to generate a random optical phase, the The output end of the third phase modulator is connected to the input end of the sixth single-mode optical fiber, and the output end of the sixth single-mode optical fiber is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit; The input end of the seventh single-mode fiber inputs another beam of optical signals decomposed by the first beam splitter, and the output end of the seventh single-mode fiber is connected to an input end of the fourth phase modulator , the other input end of the fourth phase modulator is connected to the output end of the fourth PRBS generator, and the fourth PRBS generator generates a fourth drive signal to drive the fourth phase modulator to generate a random optical phase, so The output end of the fourth phase modulator is connected to the input end of the eighth single-mode optical fiber, and the output end of the eighth single-mode optical fiber is respectively connected to the input end of the demodulation module and the input end of the arithmetic unit. 6. The quadrature modulation security optical communication device according to claim 5, further comprising a second beam splitter, a third beam splitter, a second optical coupler, a first photodetector and a second photoelectric a detector, the output end of the sixth single-mode fiber is divided into two beams of optical signals by the second beam splitter, and the output end of the eighth single-mode fiber is divided into two beams of optical signals by the third beam splitter , one of the optical signals output by the second beam splitter and one of the optical signals output by the eighth single-mode optical fiber are input to the demodulation module through the second optical coupler, and the first photodetector The input end of the detector inputs another beam of optical signal decomposed by the second beam splitter, the output end of the first photodetector is connected with the non-inverting input end of the arithmetic unit, and the output end of the second photodetector Another optical signal split by the third beam splitter is input to the input end, and the output end of the second photodetector is connected to the inverting input end of the arithmetic unit. 7. The quadrature modulation security optical communication device according to claim 6, wherein the first single-mode fiber, the third single-mode fiber, the fifth single-mode fiber and the seventh single-mode fiber are positive dispersion single-mode fibers Mode optical fiber, the second single-mode optical fiber, the fourth single-mode optical fiber, the sixth single-mode optical fiber and the eighth single-mode optical fiber are anti-dispersion single-mode optical fibers. 8 . The quadrature modulation secure optical communication device according to claim 1 , further comprising an optical amplifier, the optical amplifier is arranged on the way of the transmission optical fiber for amplifying the optical signal in the transmission optical fiber. 9. A quadrature modulation secure optical communication method, characterized in that the method is applied to the quadrature modulation secure optical communication device according to any one of claims 1 to 8, comprising the following steps: The optical pulse generated by the pulse light source generator (101) is input to the QPSK modulator (201) to generate a quadrature phase shift keying optical signal, and the optical signal is input to the CSK modulator (301) to load the intensity information, and the CSK modulator ( The two outputs of 301) are respectively connected to the two input ends of the time-domain phase encoding module (4), and then the signal encrypted by the phase encoding is coupled into the transmission fiber through the first optical coupler (501), and the transmission fiber uses The optical amplifier (601) amplifies the attenuated optical signal, and then enters the time-domain phase decoding module (8) through the first beam splitter (701) to release the random optical phase, and the outputs of the time-domain phase decoding module (8) are respectively Through two beam splitters, the output of the beam splitter is used to demodulate the QPSK signal, and the output of the beam splitter is used to detect the balance detector and obtain the original intensity information through the operation of the operator.

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