High-order integrated spatially coherent communication transceiver system based on rec laser array

Abstract

The application discloses a high-order integrated spatial coherent communication transceiving system based on a REC laser array, which comprises a transmitting end, a spatial channel and a receiving end which are connected in sequence; the transmitting end comprises a signal input module, a first FPGA, an encryption module, a control circuit, a driving circuit array, a first 8x1 REC laser array and a wavelength division multiplexer and an EDFA amplifier; an encryption key is randomly generated based on two characteristics of an arrangement combination mapping relationship of a parallel digital signal after serial-parallel conversion and the first 8x1 REC laser array and uncertainty of laser point-on signals "1" and "0". The application solves the problem that a high-speed spatial communication has extremely high requirements on system hardware performance and is difficult to realize, and can further realize double-layer encryption effect on the basis of speed reduction transmission, thereby improving the security of a high-speed communication system.

Description

Technical Field

[0001] This invention belongs to the field of space optical communication technology, specifically relating to a high-order integrated space coherent communication transceiver system based on a REC (Reconstruction Equivalent Chirp) laser array. Background Technology

[0002] Free-space optical communication, based on light waves, can transmit information in a vacuum or atmosphere. This technology eliminates the need for fiber optic cables and boasts advantages such as large communication capacity, high transmission speed, good anti-interference performance, small size, and low power consumption. However, it also suffers from beam overflow, which can affect communication security. Signal encryption, also known as signal transmission confidentiality, refers to the appropriate security protection methods adopted during communication signal transmission to prevent leaks. Signal encryption includes signal concealment and channel confidentiality. Its main purpose is to use reasonable and effective encryption methods to encrypt information, thereby preventing information theft during transmission, and even if stolen, ensuring that the correct information cannot be obtained.

[0003] For high-speed and high-capacity optical communication systems, security is one of the main research hotspots. Researchers have already proposed the technical concept of coherent laser frequency-hopping communication. The concept of frequency-hopping encryption originates from wireless frequency-hopping communication. In wireless frequency-hopping communication, the transmitter continuously switches the carrier wavelength according to a frequency-hopping pattern. The receiver can only receive complete information by switching wavelengths in the same way. Simultaneously, due to the continuous switching of the carrier, the anti-interference capability is also improved.

[0004] CN102055584B discloses an optical fiber secure communication device and its data encryption method. The device consists of a transmitter and a receiver connected by optical fiber. The transmitter includes a PPC processor unit, a field-programmable gate array (FPGA) test board, an optical transmitter module, an optical fiber coupler, and connecting optical fibers. The receiver includes a wavelength division multiplexer (WDM), connecting optical fibers, a photodetector, an FPGA test board, a PPC processor unit, and a signal output interface. At the transmitting end, two or more input data streams are forwarded by the PPC, encrypted by the FPGA, and then sent to two or more wavelength optical transmitter modules to convert electrical signals into optical signals. At the receiving end, the two or more wavelength signals are respectively converted into electrical signals by photodetectors, then decrypted by the FPGA and forwarded by the PPC. This invention improves the confidentiality of transmitted data and increases the difficulty of data decryption. The invention disclosed in CN107911171B presents a transmitter, receiver, system, and method based on coherent laser frequency hopping communication. By setting at least two tunable lasers at both the transmitter and receiver, which can operate alternately, different wavelength information and keys can be obtained in each frequency hopping cycle, greatly increasing the difficulty of data interception and improving communication security. Furthermore, this invention encrypts and modulates the input signal of the current cycle based on the key and wavelength information of the previous cycle, making it difficult for third parties to obtain or distinguish information from different cycles. Therefore, it is difficult to demodulate and decrypt the modulated signal, ensuring the security of information transmission.

[0005] However, employing frequency hopping encryption in high-speed optical communication requires increasing the frequency hopping rate. High-speed frequency hopping technology has its limitations. Due to the short dwell time, low spectral efficiency, and wide spectral occupancy of high-speed frequency-hopping signals, sidelobes can interfere with adjacent channels, resulting in crosstalk. Crosstalk is a form of distortion; its presence in communication interferes with the sampling and decision-making process in coherent demodulation, significantly impacting communication quality. Neither of the aforementioned patents can solve the crosstalk problem. Summary of the Invention

[0006] Technical Problem Solved: This invention discloses a high-order integrated space coherent communication transceiver system based on a REC laser array. Combining the parallel waveguide structure of the REC array laser and its ability to precisely control wavelength spacing, along with wavelength division multiplexing (WDM) technology based on the REC array laser, this invention effectively avoids signal crosstalk during encryption, decryption, and transmission, while reducing the communication rate requirements for each optical path. This solves the problem of extremely high hardware performance requirements and difficulties in implementing high-speed space communication. Furthermore, this invention utilizes the mapping relationship between the serial-to-parallel converted digital source and the REC array laser's permutation and combination, and the uncertainty of the laser's illumination representing signals "1" and "0," to achieve a double-layer encryption effect on top of reduced transmission speed, improving the security of the high-speed communication system. Ultimately, it achieves a simple, low-cost, high-speed, and highly secure communication system.

[0007] Technical solution:

[0008] A high-order integrated space coherent communication transceiver system based on a REC laser array, the high-order integrated space coherent communication transceiver system comprising a transmitter, a space channel and a receiver connected in sequence;

[0009] The transmitting end includes a signal input module, a first FPGA, an encryption module, a control circuit, a drive circuit array, a first 8×1 REC laser array, a wavelength division multiplexer, and an EDFA amplifier;

[0010] The first FPGA divides the serial digital signal received by the signal input module into 8 bits, converts it into 8 parallel digital signals, inputs them into the encryption module, and encrypts them according to the encryption key. The encryption key is randomly generated based on two characteristics: the mapping relationship between the serial-to-parallel converted parallel digital signals and the permutation and combination of the first 8x1REC laser array, and the uncertainty of the laser lighting signal representing "1" and "0".

[0011] The control circuit generates 8 on / off signals based on the encrypted parallel digital signal, and controls the on / off of each laser in the first 8x1REC laser array through the drive circuit array, outputting 8 different wavelength lasers with equal spacing of 0.8nm to wavelength division multiplexers.

[0012] The wavelength division multiplexer combines eight different wavelength optical signals output from the first 8x1 REC laser array into a single beam, transmits it along a single optical fiber to an EDFA amplifier for amplification, and then sends the amplified optical signal along the spatial channel to the receiving end.

[0013] Furthermore, the receiving end includes a wavelength demultiplexer, a second 8x1 REC laser array, a coherent demodulation module array, a signal processing module, and a signal output module;

[0014] The wavelength demultiplexer decomposes the received optical signal into 8 optical signals of different wavelengths, and the spatial position of each optical signal corresponds one-to-one with the spatial position before multiplexing.

[0015] The eight lasers of the second 8x1REC laser array are continuously lit, emitting eight local oscillator beams to the coherent demodulation module array. The wavelength range of the local oscillator laser output by the second 8x1REC laser array is the same as the wavelength range of the laser output by the first 8x1REC laser array.

[0016] The coherent demodulation module array coherently demodulates the eight modulated optical signals of different wavelengths received from the wavelength demultiplexer and the eight local oscillator optical signals of different wavelengths received from the second 8x1REC laser array to obtain eight analog demodulated electrical signals.

[0017] The signal processing module includes an ADC array, a decryption module, and a third FPGA connected in sequence.

[0018] The ADC array converts the received 8 analog demodulated signals into digital demodulated signals and sends them to the decryption module, which then decrypts them using a decryption key that corresponds to the encryption key.

[0019] The host port of the third FPGA is interconnected with the decryption module through an 8-channel high-speed serial GTX transceiver, which performs parallel-to-serial conversion on the 8 decrypted digital signals and sends them to the signal output module to output signals.

[0020] Furthermore, the encryption module includes a signal modulation unit and a signal randomization unit;

[0021] The signal randomization unit is used to randomly define whether the laser lighting represents binary information 1 or binary information 0.

[0022] The signal modulation unit is used to modulate the parallel digital signal into a corresponding laser control signal, using the on / off state of the carrier wave to express binary information, so that each laser in the first REC laser array is in [0, T] b Within a given time period, one of the following two waveforms is transmitted: s1(t) = A cos(2πf c t) and s2(t) = 0;

[0023]

[0024] When the laser is lit, it emits a light signal, namely s1(t) = Acos2πf. c t, where A is the amplitude of the emitted optical carrier, f c The frequency of the emitted optical carrier.

[0025] Furthermore, the control circuit includes a microcontroller and a second FPGA;

[0026] The microcontroller receives the encrypted parallel digital signal sent by the encryption module and generates an address selection signal;

[0027] The second FPGA receives the corresponding encrypted parallel digital signal and address selection signal from the microcontroller, determines the turn-on delay and enable of each laser in the first 8x1 laser array, controls the switching of each drive circuit in the drive circuit array, and completes the encryption process and signal modulation process.

[0028] Furthermore, the driving circuit array consists of 8 driving circuits, which are connected to the 8 lasers in the first 8x1REC laser array. The second FPGA controls the 8 driving circuits. When the switching signal of any one of the circuits is high, the driving current reaches the threshold current of the laser, and the laser in that circuit is lit.

[0029] Furthermore, both the first 8x1 REC laser array and the second 8x1 REC laser array consist of 8 waveguides connected in parallel, with one laser on each waveguide. The wavelength spacing between adjacent laser channels is 0.8 nm, and the output laser wavelength range is 1524.4 nm to 1530.8 nm.

[0030] Furthermore, the coherent demodulation module array is composed of 8 identical coherent demodulation units, which respectively use the zero-difference coherent detection method to coherently demodulate the received 8 optical signals of different wavelengths;

[0031] Specifically, after the signal light and local oscillator light received by the coherent demodulation unit are coherently coupled, they are converted into electrical signals by a balanced detector and enter the optical phase-locked loop. First, the loop filter filters the signal light, and then the local oscillator laser controls and drives the calculation of the frequency difference and phase difference between the signal light and the local oscillator light. This feedback is used to tune the center frequency of the local oscillator laser to ensure that w IIF =0 and the phase difference between the signal light and the local oscillator light is 0, where w IF =w s -w LO For intermediate frequency, w s w is the angular frequency of the emitted light. LO This is the angular frequency of the local oscillator.

[0032] Furthermore, the balanced detector is an avalanche photodiode with a detection wavelength range of 1280-1580nm, used to detect eight different wavelength optical signals output from the first REC laser array and the second REC laser array.

[0033] Furthermore, each laser in the first REC laser array transmits data at a rate of 1 Gbit / s; the third FPGA outputs the data at a rate of 8 Gbit / s in a parallel-to-serial manner.

[0034] Beneficial effects:

[0035] First, the high-order integrated space coherent communication transceiver system based on REC laser array of the present invention reduces the communication rate requirement for each optical path and solves the technical problem that high-speed space communication has extremely high requirements for system hardware performance and is difficult to achieve.

[0036] Secondly, the high-order integrated spatial coherent communication transceiver system based on REC laser array of the present invention has the advantage of high-precision wavelength control of REC laser array, which can achieve very low laser array wavelength spacing. In the 8×1 REC laser array, the eight lasers are respectively on eight parallel waveguides. Combined with the process of input data serial-to-parallel conversion and then modulated onto the output carrier of REC laser array through encryption module and control circuit, the signal crosstalk problem can be effectively avoided.

[0037] Third, the high-order integrated spatial coherent communication transceiver system based on REC laser array of the present invention utilizes the mapping relationship between the serial-to-parallel converted digital source and the REC array laser 1 and the uncertainty of the laser lighting signal "1" and "0" to design related encryption and decryption modules, realize double-layer encryption effect, improve the security of communication system, and the entire laser array as a whole jointly completes communication encryption and signal modulation.

[0038] Fourth, the high-order integrated spatial coherent communication transceiver system based on REC laser array of the present invention can not only realize the transmission of multi-wavelength high-order signals, accurately control the wavelength spacing, and be quickly tunable, but also be monolithically integrated, with low manufacturing cost, and has significant advantages over multiple independent lasers of different wavelengths. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the high-order integrated space coherent communication transceiver system based on REC laser array of the present invention;

[0040] Figure 2 This is a schematic diagram of the planar structure of a REC laser array;

[0041] Figure 3 A schematic diagram of the encryption key for the transmitter's encryption module;

[0042] Figure 4 This is a schematic diagram of the modulation waveforms of 8 optical signals;

[0043] Figure 5This is a diagram of the coherent demodulation structure of a single-channel optical signal;

[0044] Figure 6 This is a diagram illustrating the decryption key of the receiving end decryption module. Detailed Implementation

[0045] The following embodiments are provided to enable those skilled in the art to more fully understand the present invention, but do not limit the invention in any way.

[0046] This invention discloses a high-order integrated space coherent communication transceiver system based on a REC laser array, the high-order integrated coherent communication transceiver system comprising a transmitter, a space channel, and a receiver connected in sequence;

[0047] The transmitting end includes a signal input module, a first FPGA, an encryption module, a control circuit, a drive circuit array, a first 8x1 REC laser array, a wavelength division multiplexer, and an EDFA amplifier;

[0048] The first FPGA divides the serial digital signal received by the signal input module into 8 bits, converts it into 8 parallel digital signals, inputs them into the encryption module, and encrypts them according to the encryption key. The encryption key is randomly generated based on two characteristics: the mapping relationship between the serial-to-parallel converted parallel digital signals and the permutation and combination of the first 8x1REC laser array, and the uncertainty of the laser lighting signal representing "1" and "0".

[0049] The control circuit generates 8 on / off signals based on the encrypted parallel digital signal, and controls the on / off of each laser in the first 8x1REC laser array through the drive circuit array, outputting 8 different wavelength lasers with equal spacing of 0.8nm to wavelength division multiplexers.

[0050] The wavelength division multiplexer combines eight different wavelength optical signals output from the first 8x1 REC laser array into a single beam, transmits it along a single optical fiber to an EDFA amplifier for amplification, and then sends the amplified optical signal along the spatial channel to the receiving end.

[0051] Figure 1 This is a schematic diagram of the high-order integrated space coherent communication transceiver system based on a REC laser array according to the present invention. See also Figure 1 It includes the input signal of the transmitter, the first FPGA, the encryption module, the control circuit, the drive circuit array, the first 8×1 REC laser array, the wavelength division multiplexer, the EDFA amplifier, the wavelength division multiplexer of the space channel and the receiver, the second 8x1 REC laser array, the coherent demodulation module array, the signal processing module and the output signal.

[0052] This embodiment transmits a string of digital signals 10110001 10100000 0001001001100111 at a rate of 8 Gbit / s for detailed explanation:

[0053] The input signal is the binary valid data transmitted by the digital signal source at a rate of 8 Gbit / s;

[0054] The first FPGA is used to convert the input serial digital signal into 8 parallel digital signals;

[0055] The first 8x1 REC laser array consists of eight waveguides connected in parallel, with one laser on each waveguide. The wavelength spacing between adjacent laser channels is 0.8 nm, and the output laser wavelength range is 1524.4-1530.8 nm. Therefore, it can output eight multi-wavelength optical signals. Its planar structure schematic diagram is shown below. Figure 2 As shown, the eight lasers are LD1 to LD8 in sequence; wavelength switching is the switching of the switching modes between the array lasers. Under the combined action of the control circuit and the drive circuit, the laser array switches rapidly, lighting up the lasers of the corresponding wavelengths as needed to emit optical signals; in the embodiment, the signal modulation method is actually a kind of on / off keying method, using the on / off (absence) of the carrier wave to express binary information, also known as binary amplitude shift keying, in [0, T b Within a given time interval, the laser emits two waveforms: s1(t) = A cos(2πf) c One of t) and s2(t) = 0,

[0056]

[0057] When the laser is lit, it emits a light signal, i.e., s1(t) = A cos2πf. c In the case of t, the laser lighting signal representing either "1" or "0" is uncertain and can be freely defined. In this example, the definition of whether the laser lighting represents a signal "1" or "0" is as follows:

[0058]

[0059] The encryption key of the encryption module is set based on two characteristics: the permutation and combination of the lasers in the first 8x1 REC laser array and the uncertainty of how the laser lighting represents the signal "1" or "0". In this invention, there are 8! = 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 = 40320 ways to permutate and combine the eight lasers LD1 to LD8 in the first 8x1 REC laser array. Therefore, dividing the digital signal source sequence into 8 bits and mapping them to the eight lasers results in 40320 possibilities. In addition, the signal "1" or "0" represented by the laser lighting is uncertain. In this embodiment, the encryption key setting of the transmitting end encryption module is as follows: Figure 3 As shown, the input signal is divided into 8 bits and converted from serial to parallel. The resulting 8 digital signals are numbered a to h sequentially. 8 bits of data are transmitted to the control circuit every 1 ns. The 8 lasers LD1 to LD8 are numbered ① to ⑧ sequentially. The lasers are then arranged and combined... Figure 3 (a) in the equation represents the encryption key at the 1st ns. Figure 3 (b) in the equation is the encryption key at the 2nd ns. Figure 3 (c) in the equation represents the encryption key at the 3rd ns time. Figure 3 In this context, (d) is the encryption key at the 4th ns mark. Therefore, the encrypted digital source for controlling the on / off keying of each laser is:

[0060] Route 1: 1100; Route 2: 1101; Route 3: 0000; Route 4: 0111; Route 5: 0101; Route 6: 1100; Route 7: 0110; Route 8: 1000.

[0061] A schematic diagram of the modulation waveforms of the 8-channel optical signals is shown below. Figure 4 As shown, where Figure 4 (a) to Figure 4 The (h) diagrams in the figure represent the waveforms of the digital sources controlling the on / off state of the optical signals on channels 1 through 8. Figure 4 (i) to Figure 4 The diagrams (p) in the figure show the waveforms of the 8 modulation signals. It can also be seen from the figure that the wavelengths of the 8 optical signals are different, which reflects the tunable function of the REC laser.

[0062] The laser array emits eight optically modulated signals of different wavelengths, each transmitted at a rate of 1 Gbit / s. These signals are then combined into a single beam by a wavelength division multiplexer, transmitted along a single optical fiber, and amplified by an EDFA amplifier before being transmitted to the space channel. This completes the data transmission portion at the transmitting end. The 1 Gbit / s transmission rate per optical signal in the space channel reduces the demands on system hardware performance; however, the overall signal transmission rate for the REC laser array remains 8 Gbit / s.

[0063] At the receiving end, the wavelength demultiplexer decomposes the received optical signal into eight optical signals of different wavelengths, with the spatial position of each optical signal corresponding one-to-one with its spatial position before multiplexing. Then, the eight optical signals and the eight local oscillator signals emitted by the second 8x1 REC laser array enter the coherent demodulation module for coherent demodulation. A diagram of the single-channel optical signal coherent demodulation structure is shown below. Figure 5 As shown, after the received signal light and local oscillator light are coherently coupled, they are converted into electrical signals by a balanced detector and enter an optical phase-locked loop. First, the loop filter filters the signal light, and then the local oscillator laser controls and drives the calculation of the frequency difference and phase difference between the signal light and the local oscillator light. This feedback is used to tune the center frequency of the local oscillator laser to ensure that w IF =0 and the phase difference between the signal light and the local oscillator light is 0, which is a coherent demodulation method for zero-difference detection.

[0064] The signal processing module includes an ADC array, a decryption module, and a third FPGA;

[0065] The ADC array, with its input connected to a coherent demodulation module array, converts the received eight analog demodulated signals into digital signals. The resulting eight digital demodulated signals are as follows:

[0066] Route 1: 1100; Route 2: 1101; Route 3: 0000; Route 4: 0111; Route 5: 0101; Route 6: 1100; Route 7: 0110; Route 8: 1000.

[0067] The decryption module uses a decryption key that is symmetrical to the encryption key for decryption; in this embodiment, the decryption key setting of the receiving end decryption module is as follows: Figure 6 As shown, the 8 demodulated signals are numbered ① to ⑧ sequentially, and the decrypted digital signal is divided into 8-bit segments, numbered a to h sequentially. Figure 6 In the diagram, (a) is the decryption key at the 1st ns. Figure 6 (b) in the table is the decryption key at the 2nd ns. Figure 6 (c) in the equation represents the decryption key at the 3rd ns time. Figure 6 In this context, (d) represents the decryption key at the 4th ns mark. After decryption, the corresponding digital signals for the 8 channels are as follows:

[0068] Route 1: 1100; Route 2: 0001; Route 3: 1101; Route 4: 1010; Route 5: 0000; Route 6: 0001; Route 7: 0011; Route 8: 1001.

[0069] The third FPGA has its host port interconnected with the decryption module via an 8-channel high-speed serial GTX transceiver. This transceiver is used to perform parallel-to-serial conversion on the 8 decrypted digital signals, and finally outputs the signal 10110001101000000001001001100111 at a rate of 8 Gbit / t / s. Thus, the entire communication system completes the effective transmission of digital signals.

[0070] In this embodiment, the encryption key is known only to the sender, and the corresponding decryption key is known only to the receiver. Without knowing the key, even if the eavesdropper steals data from the channel, they will not be able to obtain the correct information.

[0071] In summary, the high-order integrated space coherent communication transceiver system based on REC array lasers described in this invention can achieve high-speed transmission of multi-wavelength high-order signals, intelligently illuminate corresponding channels of the laser array, and achieve double-layer encryption based on the overall characteristics of the laser array. Furthermore, based on the high-precision control wavelength spacing and structural characteristics of the REC array laser, and the fact that the input data is converted from serial to parallel before being loaded onto the output carrier of the REC laser array through the encryption module and control circuit, signal crosstalk problems can be effectively avoided, achieving low-cost, high-integration, and high-security communication effects, and providing a reliable solution for coherent space laser communication.

[0072] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A high-order integrated space coherent communication transceiver system based on a REC laser array, characterized in that, The high-order integrated space coherent communication transceiver system includes a transmitter, a space channel, and a receiver connected in sequence. The transmitting end includes a signal input module, a first FPGA, an encryption module, a control circuit, a drive circuit array, a first 8x1 REC laser array, a wavelength division multiplexer, and an EDFA amplifier; The first FPGA divides the serial digital signal received by the signal input module into 8 bits, converts it into 8 parallel digital signals, inputs them into the encryption module, and encrypts them according to the encryption key. The encryption key is randomly generated based on two characteristics: the mapping relationship between the serial-to-parallel converted parallel digital signal and the permutation and combination of the first 8×1REC laser array, and the uncertainty of the laser lighting signal "1" and "0". The control circuit generates 8 on / off signals based on the encrypted parallel digital signal, and controls the on / off of each laser in the first 8×1REC laser array through the drive circuit array, outputting 8 different wavelength lasers with equal intervals of 0.8nm to the wavelength division multiplexer. The wavelength division multiplexer combines eight different wavelength optical signals output from the first 8x1REC laser array into a single beam, transmits it along a single optical fiber to an EDFA amplifier for amplification, and then sends the amplified optical signal along the spatial channel to the receiving end.

2. The high-order integrated space coherent communication transceiver system based on REC laser array according to claim 1, characterized in that, The receiving end includes a wavelength demultiplexer, a second 8x1 REC laser array, a coherent demodulation module array, a signal processing module, and a signal output module; The wavelength demultiplexer decomposes the received optical signal into 8 optical signals of different wavelengths, and the spatial position of each optical signal corresponds one-to-one with the spatial position before multiplexing. The eight lasers of the second 8x1REC laser array are continuously lit, emitting eight local oscillator beams to the coherent demodulation module array. The wavelength range of the local oscillator laser output by the second 8x1REC laser array is the same as the wavelength range of the laser output by the first 8x1REC laser array. The coherent demodulation module array coherently demodulates the eight modulated optical signals of different wavelengths received from the wavelength demultiplexer and the eight local oscillator optical signals of different wavelengths received from the second 8x1REC laser array to obtain eight analog demodulated electrical signals. The signal processing module includes an ADC array, a decryption module, and a third FPGA connected in sequence. The ADC array converts the received 8 analog demodulated electrical signals into digital demodulated signals and sends them to the decryption module, which then decrypts them using a decryption key that corresponds to the encryption key. The host port of the third FPGA is interconnected with the decryption module through an 8-channel high-speed serial GTX transceiver, which performs parallel-to-serial conversion on the 8 decrypted digital signals and sends them to the signal output module to output signals.

3. The high-order integrated space coherent communication transceiver system based on REC laser array according to claim 1, characterized in that, The encryption module includes a signal modulation unit and a signal randomization unit; The signal randomization unit is used to randomly define the action of the laser lighting as representing binary information 1 or binary information 0; The signal modulation unit is used to modulate the parallel digital signal into a corresponding laser control signal, using the on / off state of the carrier wave to express binary information, so that each laser in the first 8x1 REC laser array... Send one of the following two waveforms within the specified time: and ; ； When the laser is lit, it emits a light signal, that is... ,in The amplitude of the emitted optical carrier. The frequency of the emitted optical carrier.

4. The high-order integrated spatial coherent communication transceiver system based on REC laser array according to claim 1, characterized in that, The control circuit includes a microcontroller and a second FPGA; The microcontroller receives the encrypted parallel digital signal sent by the encryption module and generates an address selection signal; The second FPGA receives the corresponding encrypted parallel digital signal and address selection signal from the microcontroller, determines the turn-on delay and enable of each laser in the first 8x1REC laser array, controls the switching of each drive circuit in the drive circuit array, and completes the encryption process and signal modulation process.

5. The high-order integrated space coherent communication transceiver system based on REC laser array according to claim 4, characterized in that, The driving circuit array consists of 8 driving circuits, which are connected to the 8 lasers in the first 8x1REC laser array. The second FPGA controls the 8 driving circuits. When the switching signal of any one of the circuits is high, the driving current reaches the threshold current of the laser, and the laser in that circuit is lit.

6. The high-order integrated space coherent communication transceiver system based on REC laser array according to claim 1, characterized in that, Both the first and second 8x1REC laser arrays consist of eight waveguides connected in parallel, with one laser on each waveguide. The wavelength spacing between adjacent laser channels is 0.8 nm, and the output laser wavelength range is 1524.4 nm to 1530.8 nm.

7. The high-order integrated space coherent communication transceiver system based on a REC laser array according to claim 2, characterized in that, The coherent demodulation module array consists of 8 identical coherent demodulation units, which use a zero-difference coherent detection method to coherently demodulate the received 8 optical signals of different wavelengths. Specifically, after the signal light and local oscillator light received by the coherent demodulation unit are coherently coupled, they are converted into electrical signals by a balanced detector and enter the optical phase-locked loop. First, the signals are filtered by a loop filter, and then the local oscillator laser is controlled to calculate the frequency difference and phase difference between the signal light and the local oscillator light. These differences are used as feedback to tune the center frequency of the local oscillator laser to ensure... And the phase difference between the signal light and the local oscillator light is 0, where, This is the intermediate frequency. The angular frequency of the emitted light. This is the angular frequency of the local oscillator.

8. The high-order integrated spatial coherent communication transceiver system based on a REC laser array according to claim 7, characterized in that, The balanced detector is an avalanche photodiode with a detection wavelength range of 1280-1580nm, used to detect eight different wavelength optical signals output from the first 8x1REC laser array and the second 8x1REC laser array.

9. The high-order integrated space coherent communication transceiver system based on REC laser array according to claim 2, characterized in that, Each laser in the first 8x1REC laser array transmits data at a rate of 1 Gbit / s; the third FPGA outputs the data at a rate of 8 Gbit / s in a parallel-to-serial manner.

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