TW202418774A - Wireless optical encryption communication method using vortex light scrambling to improve the transmission capacity, communication rate and data confidentiality of the optical communication system - Google Patents

Abstract

A wireless optical encryption communication method using vortex light scrambling includes the following steps: generating N orbital angular momentum topological charge numbers corresponding to N Gaussian light source carrier waves; converting the N separated Gaussian light source carrier waves into vortex beams, each with N encoded orbital angular momentum to obtain N vortex optical signals; generating an encrypted pairing combination; when each input terminal receives a corresponding input vortex optical signal, outputting the corresponding input vortex optical signal to the output terminal corresponding to the input terminal according to the encrypted pairing combination; each modulator performing modulation according to the vortex optical signal output by the corresponding output terminal and one of the N bit data to generate and output an optical modulation signal; performing multiplexing processing on the N optical modulation signals to generate an optical multiplexing output signal.

Description

Wireless optical encryption communication method using vortex optical perturbation

The present invention relates to a wireless optical communication method, and more particularly to a wireless optical encryption communication method using eddy optical perturbation for realizing data encryption and decryption.

The wireless optical communication system is mainly composed of light source, modulator, optical transmitter, optical receiver and additional telecommunication transmission and reception equipment. As long as they are connected to each other, they can communicate. In addition to the advantages of wireless laser communication such as no bandwidth occupation, large communication capacity and high transmission rate, wireless optical communication also has the characteristics of flexibility, economy, quick installation, easy use and no impact on municipal construction. With the maturity of atmospheric communication technology, its application is becoming more and more extensive.

In order to improve the information transmission rate of the optical communication system, in addition to adopting traditional modulation and demodulation methods such as amplitude, phase and orthogonal phase shift keying, it is also possible to increase the transmission capacity and communication rate of the optical communication system through multiplexing technology that increases the coding freedom dimension. In addition, in order to meet the necessity of secure encryption of compressed domain information transmitted on wireless optical communication channels and overcome the deficiency of traditional partial encryption that can only be performed at the application layer, it is necessary to propose a solution.

Therefore, the purpose of the present invention is to provide a wireless optical encryption communication method using eddy optical perturbation to improve the transmission capacity, communication rate and data confidentiality of the optical communication system.

Therefore, the present invention utilizes a wireless optical encryption communication method using eddy-optical perturbation, which is implemented by a transmitting-end wireless optical communication device, which is communicatively connected to a receiving-end wireless optical communication device, and includes a data compression unit, a light source generation unit, an optical filter unit having N filters and connected to the light source generation unit, an eddy-optical encoding unit connected to the optical filter unit, a transmitting-end wavelength selection switch unit connected to the eddy-optical encoding unit and having N input terminals and N output terminals, a transmitting-end control unit connected to the eddy-optical encoding unit and the transmitting-end wavelength selection switch unit, and a transmitting-end control unit connected to the eddy-optical encoding unit and the transmitting-end wavelength selection switch unit. A data compression unit, a modulation unit having N modulators and connected to the data compression unit and the transmitting end wavelength selection switch unit, and an optical multiplexing unit connected to the modulation unit, wherein the data compression unit can compress and encode N source data to generate N bit data correspondingly, the light source generation unit can provide N Gaussian light source carriers with different wavelengths, the N filters can separate the N Gaussian light source carriers to generate N separated Gaussian light source carriers, the N modulators are respectively connected to the N output terminals of the transmitting end wavelength selection switch unit, wherein N≥3, the method comprises the following steps:

(A) The transmitting end control unit generates N coded orbital angular momentum topological loads corresponding to the N Gaussian light source carriers, and transmits them to the eddy-optic encoding unit and the receiving end wireless optical communication device;

(B) the vortex optical coding unit converts the N separated Gaussian light source carriers into vortex optical beams respectively carrying N coded orbital angular momentums according to the N coded orbital angular momentum topological loads to obtain N vortex optical signals;

(C) the transmitting end control unit generates an encrypted pairing combination according to a set of control parameters using a chaotic random non-repetitive generation permutation algorithm, and transmits the set of control parameters to the receiving end wireless optical communication device and transmits the encrypted pairing combination to the transmitting end wavelength selection switch unit, wherein the encrypted pairing combination is used to indicate each input end of the transmitting end wavelength selection switch unit and its corresponding output end;

(D) for each input end of the transmitting end wavelength selection switch unit, when the input end receives an input vortex signal corresponding to one of the N vortex signals from the vortex encoding unit, outputting the corresponding input vortex signal to the output end of the transmitting end wavelength selection switch unit corresponding to the input end according to the encrypted pairing combination;

(E) for each modulator, the modulator performs modulation according to the eddy light signal outputted from the output end of the connected transmitting end wavelength selection switch unit and the bit data corresponding to one of the N bit data generated by the connected data compression unit to generate and output an optical modulation signal to the optical multiplexing unit; and

(F) The optical multiplexing unit multiplexes the N optical modulation signals to generate an optical multiplexing output signal and outputs it to the receiving end wireless optical communication device.

Another object of the present invention is to provide a wireless optical encryption communication method using eddy optical perturbation to improve the transmission capacity, communication rate and data confidentiality of the optical communication system.

Therefore, the present invention uses a wireless optical encryption communication method using eddy-optical perturbation, which is implemented by a receiving-end wireless optical communication device, which is communicatively connected to a transmitting-end wireless optical communication device and includes a data recovery unit, a photodemultiplexing unit, a eddy-optical decoding unit connected to the photodemultiplexing unit, and a eddy-optical decoding unit connected to the eddy-optical decoding unit and having N input ports and N output ports. A receiving end wavelength selection switch unit of the receiving end, a receiving end control unit connected to the eddy optical decoding unit and the receiving end wavelength selection switch unit, and a demodulation unit having N demodulators and connected to the data recovery unit and the receiving end wavelength selection switch unit, wherein the N demodulators are respectively connected to the N output terminals of the receiving end wavelength selection switch unit, and the method comprises the following steps:

(A) the photodemultiplexing unit demultiplexes the optical multiplexed output signal to generate the N sets of photodemultiplexing signals and input them into the eddy-optic decoding unit;

(B) the receiving end control unit generates N decoded orbital angular momentum topological load numbers according to the N encoded orbital angular momentum topological load numbers transmitted by the transmitting end control unit, and transmits the decoded orbital angular momentum topological load numbers to the eddy optical decoding unit;

(C) the vortex optical decoding unit decodes the N sets of photomultiplexing signals into N Gaussian light signals with zero orbital angular momentum according to the N decoded orbital angular momentum topological charges;

(D) the receiving end control unit generates an encryption pair combination using a chaotic random non-repetitive generation permutation algorithm according to the set of control parameters transmitted by the transmitting end control unit, generates a decryption pair combination according to the encryption pair combination, and transmits the decryption pair combination to the receiving end wavelength selection switch unit, wherein the decryption pair combination is used to indicate each input end of the receiving end wavelength selection switch unit and its corresponding output end;

(E) for each input end of the receiving end wavelength selection switch unit, when the input end receives an input Gaussian light signal corresponding to one of the N Gaussian light signals from the vortex optical decoding unit, the corresponding input Gaussian light signal is output to the output end of the receiving end wavelength selection switch unit matched with the input end according to the decryption pairing combination;

(F) for each demodulator, the demodulator demodulates the Gaussian optical signal outputted from the output end of the connected receiving end wavelength selection switch unit to generate a corresponding data bit; and

(G) The data restoration unit restores each data bit to generate N source data.

The utility of the present invention is that the N separated Gaussian light source carriers are converted into the N vortex light signals by the vortex light encoding unit, so as to realize multiplex transmission by using the vortex light beam, thereby improving the transmission capacity and communication rate of optical communication. In addition, according to the encryption pairing combination generated by the transmitting end control unit, the corresponding input vortex light signal is output to the output end of the transmitting end wavelength selection switch unit corresponding to the input end, so as to scramble the transmission path of the vortex light signal, thereby improving the transmission security of optical communication.

Referring to Figures 1 and 2, an embodiment of the wireless optical encryption communication method using eddy optical perturbation of the present invention is implemented by a wireless optical communication system. The wireless optical communication system includes a transmitting end wireless optical communication device 1 and a receiving end wireless optical communication device 2 communicatively connected to the transmitting end wireless optical communication device 1.

The transmitting end wireless optical communication device 1 includes a data compression unit 11, a light source generating unit 12, an optical filter unit 13 having N filters and connected to the light source generating unit 12, an eddy current encoding unit 14 connected to the optical filter unit 13, a transmitting end wavelength selection switch unit 15 connected to the eddy current encoding unit 14 and having N input terminals and N output terminals, A transmitter control unit 16 connected to the vortex optical coding unit 14 and the transmitter wavelength selection switch unit 15, a modulation unit 17 having N modulators and connected to the data compression unit 11 and the transmitter wavelength selection switch unit 15, an optical multiplexing unit 18 connected to the modulation unit 17, and a wireless optical transmission unit 19 connected to the optical multiplexing unit 18. The data compression unit 11 can compress and encode N source data to generate N bit data. The light source generation unit 12 can provide N Gaussian light source carriers with different wavelengths. The N filters can separate the N Gaussian light source carriers to generate N separated Gaussian light source carriers. The N modulators are respectively connected to the N output terminals of the transmitting end wavelength selection switch unit 15, where N≥3.

The receiving-end wireless optical communication device 2 includes a data recovery unit 21, a wireless optical receiving unit 22, a photodemultiplexing unit 23 connected to the wireless optical receiving unit 22, a vortex optical decoding unit 24 connected to the photodemultiplexing unit 23, a receiving-end wavelength selection switch unit 25 connected to the vortex optical decoding unit 24 and having N input terminals and N output terminals, a receiving-end control unit 26 connected to the vortex optical decoding unit 24 and the receiving-end wavelength selection switch unit 25, and a demodulation unit 27 having N demodulators and connecting the data recovery unit 21 and the receiving-end wavelength selection switch unit 25, wherein the N demodulators are respectively connected to the N output terminals of the receiving-end wavelength selection switch unit 25.

In this embodiment, the vortex optical encoding unit 14 and the vortex optical decoding unit 24 may be a programmable liquid crystal spatial light modulator, which can program and control light waves to present unequal phases to achieve vortex light beams carrying various orbital angular momentums. Furthermore, the transmitting-end wavelength selection switch unit 15 and the receiving-end wavelength selection switch unit 25 are programmable wavelength selection switches for applying a liquid crystal spatial light modulator, which can change the incident and reflection angles of the vortex light signal and change the optical spatial transmission path by programmable regulation of the deflection of the liquid crystal molecules in and out of the liquid crystal spatial light modulator, thereby changing the input-output coordination relationship of the N input terminals and the N output terminals of the transmitting-end wavelength selection switch unit 15, and the N output terminals of the receiving-end wavelength selection switch unit 25. The input-output matching relationship of the input end and the N output ends can obtain N! pairing combinations for indicating the bijective relationship of the N input ends and the N output ends from the N input ends and the N output ends of the transmitting end wavelength selection switch unit 15. Similarly, the N input ends and the N output ends of the receiving end wavelength selection switch unit 25 can also obtain N! pairing combinations for indicating the bijective relationship of the N input ends and the N output ends. In addition, the data compression unit 11, the data recovery unit 21, the transmitting end control unit 16 and the receiving end control unit 26 can be implemented by electronic components with computing capabilities such as embedded system components and digital circuits.

It is worth noting that each pairing combination corresponds to a matrix pattern, and each matrix pattern is an N×N matrix in which only one element in each row element (matrix element) and each column element is '1' and the rest are '0'. The N columns in each matrix correspond to the N input terminals of the transmitting end wavelength selection switch unit 15, and the N rows in each matrix correspond to the N output terminals of the transmitting end wavelength selection switch unit 15. The N! pairing combinations are the set of all possibilities of the matrix pattern. , i,j=1,2,3…,N; Assume N=3, a total of 3! pair combinations, the matrix patterns of all possible sets are: , , , , and There are six types of patterns, with matching combinations as As an example, the matrix pattern of the matrix element TR ₁₂ = 1 in the matrix pattern can indicate that any signal data input from the first input terminal of the transmitting end wavelength selection switch unit 15 will only be output from its corresponding second output terminal; TR ₂₃ = 1 can indicate that any signal data input from the second input terminal of the transmitting end wavelength selection switch unit 15 will only be output from its corresponding third output terminal; TR ₃₁ = 1 can indicate that any signal data input from the third input terminal of the transmitting end wavelength selection switch unit 15 will only be output from its corresponding first output terminal.

The data compression unit 11 receives N source data User#1-User#N transmitted from the outside, and compresses and encodes the N source data User#1-User#N to generate N bit data U ₁ -U _N accordingly.

After the light source generating unit 12 generates N Gaussian light source carriers λ ₁ ~λ _N of different wavelengths, they are transmitted to the N filters of the optical filtering unit 13 respectively; then, the N filters generate N separated Gaussian light source carriers λ ₁ /λ ₂ …λ _N-1 /λ _N according to the received N Gaussian light source carriers λ ₁ ~λ _N ; each filter can be realized by an optical element such as a spatial light modulator (SLM) or a fiber Bragg grating (FBG).

The following will illustrate the operation of each component in the wireless communication system through an embodiment of the wireless optical encryption communication method using eddy optical perturbation of the present invention. The embodiment includes a matching prediction model establishment process, a sending process and a receiving process.

1 and 3 , the pairing prediction model establishment procedure illustrates how the transmitter control unit 16 establishes a pairing prediction model, and includes the following steps.

In step 31, the transmitting end control unit 16 generates multiple sets of training pair combinations using a chaotic random non-repetitive generation permutation algorithm according to a set of control parameters, and obtains multiple training data according to the training pair combinations, wherein each training data is composed of a label pair combination with one of the training pair combinations as the label of the corresponding training data and Y sets of training pair combinations corresponding to the label pair combination. The control parameter group is, for example, an initial condition (X ₀ ) and a control parameter value (C). By using the chaotic random non-repetitive generation permutation algorithm, as long as the initial condition X ₀ and the control parameter value C are given, X ₁ , X ₂ , ..., X _M (M>>N) can be generated. Then, a training pair combination is generated according to X ₁ ~ X _N , and the next training pair combination is generated according to X _N+1 ~ X _2N , ..., and so on, to obtain the training pair combinations.

In step 32, the transmitting end control unit 16 uses a machine learning algorithm based on the training data to obtain the pairing prediction model, wherein the pairing prediction model is used to predict a current pairing adoption combination based on the previous Y sets of pairing adoption combinations. It is worth mentioning that the training data are randomly sampled and divided into a training set and a test set, and the pairing prediction model is obtained through a training, testing, and validation phase procedure. In this embodiment, the machine learning algorithm is, for example, a regression analysis method, but is not limited thereto.

1 , 2 , 4 and 5 , the sending process illustrates how the transmitting end wireless optical communication device 1 sends data to the receiving end wireless optical communication device 2 , and includes the following steps.

In step 311, the light source generation unit 12 generates N Gaussian light source carriers with different wavelengths and outputs them to the optical filtering unit 13. For example, the light source generation unit 12 generates N=3 Gaussian light source carriers with different wavelengths λ ₁ -λ ₃ .

In step 312, the N filters of the optical filter unit 13 separate the N Gaussian light source carriers to generate N separated Gaussian light source carriers, and output them to the eddy current encoding unit 14. Continuing the above example, the optical filter unit 13 provides three corresponding numbers of filters to separate the three Gaussian light source carriers λ ₁ ~λ ₃ to generate three separated Gaussian light source carriers λ ₁ /λ ₂₁ /λ ₃ which are output to the eddy current encoding unit 14 in parallel.

In step 313, the transmitting end control unit 16 generates N coded orbital angular momentum topology load numbers corresponding to the N Gaussian light source carriers, and transmits them to the eddy optical coding unit 14 and the receiving end wireless optical communication device 2. For example, the transmitting end control unit 16 generates three coded orbital angular momentum topology load numbers l ₁ ~ l ₃ corresponding to the three Gaussian light source carriers λ1 ~ λ3.

In step 314, the vortex encoding unit 14 converts the N separated Gaussian light source carriers into vortex beams with N coded orbital angular momenta according to the N coded orbital angular momentum topology numbers to obtain N vortex optical signals. Continuing the above example, the vortex optical encoding unit 14 converts the three separated Gaussian light source carriers λ ₁ , λ ₂ , λ ₃ into vortex optical signals λ ₁ ( l ₁ ), λ 2 ( l ₂ ), λ ₃ ( l ₃ ) with three coded orbital angular momenta according to the three coded orbital angular momentum topology numbers l ₁ , l ₂ , l _{3 .}

In step 315, the transmitting end control unit 16 generates an encrypted pairing combination using the chaotic random non-repetitive permutation algorithm according to the set of control parameters in step 31, and transmits the set of control parameters to the receiving end wireless optical communication device 2 and transmits the encrypted pairing combination to the transmitting end wavelength selection switch unit 15, wherein the encrypted pairing combination is used to indicate each input end of the transmitting end wavelength selection switch unit 15 and its corresponding output end.

It is worth mentioning that step 315 also includes the following sub-steps (see FIG. 6 ).

In sub-step 315A, the transmitting end control unit 16 generates a random time sequence of length N using a chaotic equation according to the set of control parameters. The set of control parameters is, for example, an initial condition (X ₀ ) and a control parameter value (C), and the chaotic equation is, for example, X _n+1 =C×X _n ×(1-X _n ). Therefore, as long as the initial condition X ₀ and the control parameter value C are given, X ₁ , X ₂ , ..., X _N can be generated according to the chaotic equation. In this way, a random time sequence of length N is obtained. For example, assuming that N=3 and the random time sequence is: {0.5, 0.2, 0.1}.

In sub-step 315B, the transmitting end control unit 16 maps each value in the random time sequence to a corresponding positive integer sequence. The transmitting end control unit 16 converts the random time sequence by a preset mapping function to respectively map the N random real numbers in the random time sequence to positive integer sequences with values ranging from 1 to N according to their values. Continuing with the above example, the random time series {0.5, 0.2, 0.1} is converted to {3, 2, 1} after non-repeating numerical values are converted by the default mapping function, wherein the positive integer sequence corresponding to the minimum value 0.1 in the random time series is 1, the positive integer sequence corresponding to the middle value 0.2 is 2, and the positive integer sequence corresponding to the maximum value 0.5 is 3.

In sub-step 315C, the transmitter control unit 16 converts the N positive integer sequences into a permutation matrix as the encryption pair combination, wherein the encryption pair combination is used to indicate each input terminal of the transmitter wavelength selection switch unit 15 and its corresponding output terminal. Continuing the above example, the transmitter control unit 16 converts {3,2,1} into a permutation matrix , as the encryption pairing combination, the matrix element TR ₁₃ =1 in the encryption pairing combination can indicate that any signal data input from the first input terminal of the transmitting end wavelength selection switch unit 15 will only be output from its corresponding third output terminal; TR ₂₂ =1, can indicate that any signal data input from the second input terminal of the transmitting end wavelength selection switch unit 15 will only be output from its corresponding second output terminal; TR ₃₁ =1, can indicate that any signal data input from the third input terminal of the transmitting end wavelength selection switch unit 15 will only be output from its corresponding first output terminal.

In sub-step 315D, the transmitting end control unit 16 transmits the set of control parameters to the receiving end wireless optical communication device 2 and transmits the encrypted pairing combination to the transmitting end wavelength selection switch unit 15.

In step 316, the transmitting end control unit 16 uses the pairing prediction model to predict a predicted encryption pairing combination corresponding to the Y groups of encryption pairing combinations generated in the previous 1 to Y steps 315 (that is, based on the Y groups of encryption pairing combinations generated in the previous 1 to Y steps 315, predict the encryption pairing combination that may be generated in this step 315).

In step 317, the transmitting end control unit 16 compares the encryption pairing combination generated in step 315 with the predicted encryption pairing combination, and updates a prediction accuracy rate according to the comparison result. The higher the prediction accuracy rate, the higher the variability of the encryption pairing combination generated by the chaotic random non-repetitive permutation algorithm has a high significant characteristic pattern; in other words, the threat of unauthorized persons using various machine learning prediction models to crack the encryption pairing combination is higher.

In step 318, the transmitting end control unit 16 determines whether the encryption pairing combination generated according to step 315 has a risk of cracking according to the prediction accuracy. When the transmitting end control unit 16 determines that there is a risk of cracking, the process proceeds to step 319; when the transmitting end control unit 16 determines that there is no risk of cracking, the process proceeds to step 320. The transmitting end control unit 16 determines whether the prediction accuracy is greater than a threshold value to determine whether the encryption pairing combination generated according to step 315 has a risk of cracking. When the transmitting end control unit 16 determines that the prediction accuracy is greater than the threshold value, it is determined that the encryption pairing combination generated according to step 315 has a risk of being cracked; when the transmitting end control unit 16 determines that the prediction accuracy is not greater than the threshold value, it is determined that the encryption pairing combination generated according to step 315 does not have a risk of being cracked, and the set of control parameters is continued to maintain the original predetermined eddy light disturbance pattern.

In step 319, the transmitter control unit 16 changes the set of control parameters and returns to step 315 to generate a new encryption pairing combination according to another set of control parameters after the change to change the scrambling pattern of the eddy light.

In step 320, for each input terminal of the transmitting end wavelength selection switch unit 15, when the input terminal receives an input vortex signal corresponding to one of the N vortex signals from the vortex encoding unit 14, the corresponding input vortex signal is output to the output terminal of the transmitting end wavelength selection switch unit 15 corresponding to the input terminal according to the encryption pairing combination. After the matrix pattern of is used as the encryption pairing combination to output the corresponding input vortex signal λ ₁ ( l ₁ )/λ ₂ ( l ₂ )/λ ₃ ( l ₃ ) to the output end of the transmitting end wavelength selection switch unit 15 corresponding to the input end, the spatial output sequence of λ ₁ ( l ₁ ), λ ₂ ( l ₂ ), λ ₃ ( l ₃ ) will become λ ₃ ( l ₃ ), λ ₂ ( l ₂ ), λ ₁ ( l ₁ ). In this way, the spatial transmission path of the vortex signal entering the modulation unit 17 is changed to achieve the transformation of the carrier vortex of the source data User#1~User#N.

In step 321, the data compression unit 11 compresses and encodes the N source data User#1 to User#N to generate the N bit data U ₁ to U _N . For example, when N=3, the three bit data are U ₁ to U ₃ .

In step 322, for each modulator, the modulator performs modulation according to the vortex optical signal output from the output end of the connected transmitting end wavelength selection switch unit 15 and the bit data corresponding to one of the N bit data generated by the connected data compression unit 11 to generate and output an optical modulation signal to the optical multiplexing unit 18. The modulator connected to the output end corresponding to the output vortex light signal λ ₃ ( l ₃ ) modulates the bit data U ₁ corresponding to one of the N bit data to generate the optical modulation signal U ₁ [λ ₃ ( l ₃ )], the modulator connected to the output end corresponding to the output vortex light signal λ ₂ ( l ₂ ) modulates the bit data U ₂ corresponding to one of the N bit data to generate the optical modulation signal U ₂ [λ ₂ ( l ₂ )], and the modulator connected to the output end corresponding to the output vortex light signal λ ₁ ( l ₁ ) modulates the bit data U ₃ corresponding to one of the N bit data to generate the optical modulation signal U ₃ [λ ₁ ( l ₁ )]. The spatial output sequence of λ ₁ ( l ₁ ), λ ₂ ( l ₂ ), λ ₃ ( l ₃ ) is transformed into λ ₃ ( l ₃ ), λ ₂ ( l ₂ ), λ ₁ ( l ₁ ) by the eddy-optic encoding unit 14 and the transmitting-end wavelength selection switch unit 15, and the encryption pairing combination generated by the transmitting-end control unit 16 according to the set of control parameters is different each time. In this way, the bit data U ₁ ~U ₃ of this time and the bit data U ₁ ~U ₃ of the next time are not all matched with the same carrier set λ ₁ ~λ ₃ , thus forming an eddy-optic perturbation conversion mechanism.

In step 323, the optical multiplexing unit 18 multiplexes the N optical modulated signals to generate an optical multiplexed output signal, and transmits the signal to the wireless optical receiving unit 22 of the receiving end wireless optical communication device 2 via the wireless optical transmission unit 19. The optical multiplexing unit 18 multiplexes the N optical modulated signals _U1 [ _λ3 ( l3 ₎ ], _U2 [ _λ2 ( l2 ₎ ], and _U3 [ _λ1 ( l1 )] into an optical multiplexed output signal _U1 [ _λ3 ( l3 )]~ _U3 [ _λ1 ( _l1 )]. In this embodiment, optical elements such as array waveguide fiber gratings or Bragg fiber gratings may be used to perform optical wavelength division multiplexing on the N optical modulated signals, but the present _invention is not _limited thereto.

1, 2 and 7, the receiving process illustrates how the receiving end wireless optical communication device 2 restores the data sent by the transmitting end wireless optical communication device 1, and includes the following steps.

In step 501 , after the wireless optical receiving unit 22 of the receiving-end wireless optical communication device 2 receives the optical multiplexed output signal, the optical multiplexed output signal is output to the optical demultiplexing unit 23 .

In step 502, the photodemultiplexing unit 23 sequentially demultiplexes the optical multiplexing output signal according to the N vortex optical signals λ ₁ ( l ₁ ), λ ₂ ( l ₂ ), λ ₃ ( l ₃ ) of different wavelengths to generate the N groups of photodemultiplexing signals and output them to the vortex optical decoding unit 24. The photodemultiplexing unit 23 demultiplexes the optical multiplexed output signal _U1 [ _λ3 ( l3 ₎ ]~ _U3 [ _λ1 ( l1 )] into the three groups of photodemultiplexing signals U3[ _λ1 ( _{l1 )} ], U2[ _λ2 ( l2 ₎ ], _{U1 [λ3} ( l3 )] according to the N vortex optical signals with different wavelengths _λ1 ( _l1 ) , _λ2 ( _{l2 )} , _λ3 ( l3 ). In the present embodiment, the photodemultiplexing unit 23 can perform _wavelength division and demultiplexing processing by a ₁ ×N centralized array waveguide fiber grating (AWG) or N distributed Bragg fiber gratings ( FBG ), but _is not limited thereto.

In step 503, the receiving end control unit 26 generates N decoded orbital angular momentum topology load numbers according to the N encoded orbital angular momentum topology load numbers transmitted by the transmitting end control unit 16, and transmits them to the eddy light decoding unit 24. Continuing the above example, the receiving end control unit 26 generates three decoded orbital angular momentum topology load numbers -11 , -12 , _-13 according to the three encoded orbital angular momentum topology load numbers _l1 , _{l2 ,} l3 . (That is, the three decoded orbital angular momentum topology load numbers are restored to _be symmetrical to _the three encoded orbital angular momentum topology load numbers)

In step 504, the vortex optical decoding unit 24 decodes the N sets of photodemultiplexing signals into N Gaussian light signals with zero orbital angular momentum according to the N decoded orbital angular momentum topological loads, and outputs them to the receiving end wavelength selection switch unit 25. Continuing with the above example, the vortex optical decoding unit 24 decodes the three sets of photomultiplexed signals U ₃ [λ 1 ( l 1 )], U ₂ [ λ ₂ ( l ₂ )], U 1 [λ ₃ ( l ₃ )] into three Gaussian light signals U ₃ [λ ₁ ], U ₂ [ λ ₂ ], U ₁ [ λ ₃ ] with zero orbital angular momentum according to the three decoded orbital angular momentum topological load numbers - l ₁ , - _{l 2 , -} l ₃ . Since the three encoded orbital angular momentum topology load numbers l ₁ , l ₂ , l ₃ correspond to the three Gaussian light source carriers λ ₁ , λ ₂ , λ ₃ , respectively, the three decoded orbital angular momentum topology load numbers - l ₁ , - l ₂ , - l ₃ generated by the receiving end control unit 26 must also correspond to the three Gaussian light source carriers λ ₁ , λ ₂ , λ ₃ , respectively. Therefore, the vortex optical decoding unit 24 will decode the photodemultiplexing signal U ₃ [λ ₁ ( l ₁ )] corresponding to λ ₁ according to - l ₁ to decode the Gaussian light signal U ₃ [λ ₁ ], and will decode the photodemultiplexing signal U ₂ [λ ₂ ( l ₂ )] corresponding to λ ₂ according to - l ₂ to decode the Gaussian light signal U ₂ [λ ₂ ], and will decode the photodemultiplexing signal U ₁ [λ ₃ ( l ₃ )] corresponding to λ ₃ according to - l ₃ to decode the Gaussian light signal U ₁ [λ ₃ ].

In step 505, the receiving end control unit 26 generates an encryption pairing combination using the chaotic random non-repetitive permutation algorithm according to the set of control parameters transmitted by the transmitting end control unit 16, generates a decryption pairing combination according to the encryption pairing combination, and transmits the decryption pairing combination to the receiving end wavelength selection switch unit 25, wherein the decryption pairing combination is used to indicate each input terminal of the receiving end wavelength selection switch unit 25 and its corresponding output terminal.

It is worth mentioning that step 505 also includes the following sub-steps (see FIG. 8 ).

In sub-step 505A, the receiving end control unit 26 generates a random time sequence of length N using the chaotic equation according to the set of control parameters. Since the set of control parameters is the set of control parameters used by the transmitting end control unit 16 to generate the random time sequence, the chaotic equation used by the transmitting end control unit 16 and the chaotic equation used by the receiving end control unit 26 are also the same equation, so the random time sequence generated by the receiving end control unit 26 using the chaotic equation according to the set of control parameters is the same as the random time sequence generated by the transmitting end control unit 16 using the chaotic equation according to the set of control parameters. Continuing the above example, the random time sequence generated by the receiving end control unit 26 is {0.5, 0.2, 0.1}.

In sub-step 505B, the receiving end control unit 26 maps each value in the random time sequence to a corresponding positive integer sequence. Similarly, the random time sequence {0.5, 0.2, 0.1} is converted to {3, 2, 1} after non-repeating numerical conversion by the default mapping function.

In sub-step 505C, the receiving end control unit 26 converts the N positive integer sequences into a permutation matrix to generate the same encryption pair combination as step 315. Similarly, the receiving end control unit 26 converts {3,2,1} into the permutation matrix .

In sub-step 505D, the receiving end control unit 26 generates a decryption pairing combination according to the encryption pairing combination, and transmits the decryption pairing combination to the receiving end wavelength selection switch unit 25, wherein the decryption pairing combination is used to indicate each input terminal of the receiving end wavelength selection switch unit 25 and its corresponding output terminal. In this embodiment, the matrix pattern corresponding to the decryption pairing combination and the matrix pattern corresponding to the encryption pairing combination are mutually transposed, so the receiving end control unit 26 can obtain the decryption pairing combination by transposing the permutation matrix. Continuing with the above example, the permutation matrix is transposed. Transpose to get (Right now, The product of these two matrices will form a unit matrix.

In step 506, for each input end of the receiving end wavelength selection switch unit 25, when the input end receives an input Gaussian light signal corresponding to one of the N Gaussian light signals from the vortex optical decoding unit 24, the corresponding input Gaussian light signal is output to the output end of the receiving end wavelength selection switch unit 25 that matches the input end according to the decryption pair combination. After using the matrix pattern as the decryption pairing combination to output the corresponding input Gaussian light signal U ₃ [λ ₁ ] /U ₂ [λ ₂ ] /U ₁ [λ ₃ ] to the output end of the receiving end wavelength selection switch unit 25 corresponding to the input end, the spatial output order of U ₃ [λ ₁ ], U ₂ [λ ₂ ], U ₁ [λ ₃ ] will become U ₁ [λ ₃ ], U ₂ [λ ₂ ], U ₃ [λ ₁ ].

In step 507, for each demodulator, the demodulator demodulates the Gaussian light signal outputted from the output end of the connected receiving end wavelength selection switch unit 25 to generate a corresponding bit data, and outputs it to the data recovery unit 21. Continuing with the above example, each demodulator demodulates U ₁ [λ ₃ ] /U ₂ [λ ₂ ] /U ₃ [λ ₁ ] to unload the Gaussian light source carrier, thereby generating a corresponding bit data U ₁ /U ₂ /U ₃ . In this embodiment, each demodulator can perform demodulation by a photodetector, but is not limited thereto.

In step 508, the data restoration unit 21 restores each bit of the data to generate the N source data. Continuing with the above example, the data restoration unit 21 restores each bit of the data U ₁ /U ₂ /U ₃ to generate the three source data User#1~User#3. In this way, the original format of the source image data User#1~User#3 is correctly restored and interpreted.

In summary, the present invention generates the encryption pair combination through the transmitting end control unit 16, and forms a vortex optical perturbation sequence transformation mechanism for the bit data U ₁ ~U _N after the transmission encryption process, so that the N bit data can be correctly interpreted through the decryption pair combination corresponding to the encryption pair combination during the subsequent decryption, and then the source data User#1~User#N can be restored. In this way, multiple vortex optical perturbation sequence transformation mechanisms on the physical layer are used to generate encryption performance to solve the dilemma that the image can only be partially encrypted on the application layer, thereby reducing the security of wireless optical communication when transmitting images. In addition, by adding the coding of multi-modal orbital angular momentum and integrating the perturbation transformation vortex optical system to realize multi-dimensional multiplexed encrypted transmission, the transmission capacity of optical communication and the security of information transmission are improved. Furthermore, by constructing chaotic encryption and obtaining the predicted encryption pairing combination through machine learning regression analysis to monitor the threat of predictive cracking, the control parameters are actively changed to strengthen the physical layer transmission security with privacy, so the purpose of this invention can be achieved.

However, the above is only an embodiment of the present invention and should not be used to limit the scope of implementation of the present invention. All simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still within the scope of the present patent.

User#1~User#N Source dataλ ₁ ~λ ₃ ··· Gaussian light source carrierλ ₁ ( l ₁ )~λ ₃ ( l ₃ ) Vortex light signalU ₁ ~U ₃ ·· Bit dataU ₁ [λ ₃ ( l ₃ )]、U ₂ [λ ₂ ( l ₂ )]、U ₃ [λ ₁ ( l ₁ )]Optical modulation signalU ₁ [λ ₃ ( l ₃ )]~U ₃ [λ ₁ ( l ₁ )]Optical multiplexed output signalU ₃ [λ ₁ ( l ₁ )]、U ₂ [λ ₂ ( l ₂ )]、U ₁ [λ ₃ ( l ₃ )]Photodemultiplexed signalU ₃ [λ ₁ ]、U ₂ [λ ₂ ]、U ₁ [λ ₃ ] Gaussian light signal1········ Transmitter-side wireless optical communication device 11······ Data compression unit 12······ Light source generation unit 13······ Optical filtering unit 14······ Eddy optical encoding unit 15······ Transmitter-side wavelength selection switch unit 16······ Transmitter-side control unit 17······ Modulation unit 18······ Optical multiplexing unit 19······ Wireless optical transmission unit 2········ Receiving-side wireless optical communication device 21······ Data recovery unit 22······ Wireless optical receiving unit 23······· Optical demultiplexing unit 24······ Eddy optical decoding unit 25······ Receiver wavelength selection switch unit 26 Receiver control unit 27 Demodulation unit 31~32 Steps 311~323 Steps 315A~315D Sub-steps 501~508 Steps 505A~505D Sub-steps

Other features and effects of the present invention will be clearly presented in the implementation method of the reference figures, in which: Figures 1 and 2 are both block diagrams, which are used to illustrate a wireless optical communication system for implementing an embodiment of the wireless optical encryption communication method using vortex optical perturbation of the present invention; Figure 3 is a flow chart, which illustrates a pairing prediction model establishment procedure of an embodiment of the wireless optical encryption communication method using vortex optical perturbation of the present invention; Figures 4 and 5 are both flow charts, which are used to illustrate a sending procedure of an embodiment of the wireless optical encryption communication method using vortex optical perturbation of the present invention; Figure 6 is a flow chart, which illustrates how to generate an encrypted pairing combination; Figure 7 is a flow chart, which illustrates a receiving procedure of an embodiment of the wireless optical encryption communication method using vortex optical perturbation of the present invention; and Figure 8 is a flow chart illustrating how to generate a decryption pair combination.

1: Transmitter wireless optical communication device

11: Data compression unit

12: Light source generation unit

13: Optical filter unit

14: Eddy current encoding unit

15: Transmitter wavelength selection switch unit

16: Transmitter control unit

17: Modulation unit

18: Optical multiplexing unit

19: Wireless optical transmission unit

Claims (8)

A wireless optical encryption communication method using eddy optical perturbation is implemented by a transmitting end wireless optical communication device, the transmitting end wireless optical communication device is communicatively connected to a receiving end wireless optical communication device, and includes a data compression unit, a light source generation unit, an optical filter unit having N filters and connected to the light source generation unit, an eddy optical encoding unit connected to the optical filter unit, a transmitting end wavelength selection switch unit connected to the eddy optical encoding unit and having N input ends and N output ends, a transmitting end control unit connected to the eddy optical encoding unit and the transmitting end wavelength selection switch unit, and a A modulation unit having N modulators connected to the data compression unit and the transmitting end wavelength selection switch unit, and an optical multiplexing unit connected to the modulation unit, wherein the data compression unit can compress and encode N source data to generate N bit data correspondingly, the light source generation unit can provide N Gaussian light source carriers with different wavelengths, the N filters can separate the N Gaussian light source carriers to generate N separated Gaussian light source carriers, the N modulators are respectively connected to the N output ends of the transmitting end wavelength selection switch unit, wherein N≥3, the method comprises the following steps: (A) The transmitting end control unit generates N coded orbital angular momentum topological load numbers corresponding to the N Gaussian light source carriers, and transmits them to the eddy light encoding unit and the receiving end wireless optical communication device; (B) The eddy light encoding unit converts the N separated Gaussian light source carriers into eddy light beams with N coded orbital angular momentums according to the N coded orbital angular momentum topological load numbers, so as to obtain N eddy light signals; (C) The transmitting end control unit generates an encrypted pairing combination according to a set of control parameters using a chaotic random non-repetitive generation permutation algorithm, and transmits the set of control parameters to the receiving end wireless optical communication device and transmits the encrypted pairing combination to the transmitting end wavelength selection switch unit, wherein the encrypted pairing combination is used to indicate each input end of the transmitting end wavelength selection switch unit and its corresponding output end; (D) For each input end of the transmitting end wavelength selection switch unit, when the input end receives an input vortex signal corresponding to one of the N vortex signals from the vortex encoding unit, the corresponding input vortex signal is output to the output end of the transmitting end wavelength selection switch unit corresponding to the input end according to the encrypted pairing combination; (E) For each modulator, the modulator modulates the vortex optical signal output from the output end of the connected transmitting end wavelength selection switch unit and the bit data corresponding to one of the N bit data generated by the connected data compression unit to generate and output an optical modulated signal to the optical multiplexing unit; and (F) The optical multiplexing unit multiplexes the N optical modulated signals to generate an optical multiplexed output signal and outputs it to the receiving end wireless optical communication device. The wireless optical encryption communication method using vortex optical perturbation as described in claim 1, wherein step (C) includes the following sub-steps: (C-1) the transmitter control unit generates a random time sequence of length N using a chaotic equation according to the set of control parameters; (C-2) the transmitter control unit maps each value in the random time sequence to a corresponding positive integer sequence; (C-3) the transmitter control unit converts the N positive integer sequences into a permutation matrix as the encryption pairing combination, wherein the encryption pairing combination is used to indicate each input terminal of the transmitter wavelength selection switch unit and its corresponding output terminal; and (C-4) The transmitting end control unit transmits the set of control parameters to the receiving end wireless optical communication device and transmits the encrypted pairing combination to the transmitting end wavelength selection switch unit. The wireless optical encryption communication method using vortex optical perturbation as described in claim 1 further comprises the following steps before step (A): (G) The transmitting end control unit generates multiple sets of training pair combinations using the chaotic random non-repetitive generation permutation algorithm according to the set of control parameters in step (C), and obtains multiple training data according to the training pair combinations, wherein each training data is composed of a label pair combination with one of the training pair combinations as the label of the corresponding training data and Y sets of training pair combinations corresponding to the label pair combination; and (H) The transmitting end control unit uses a machine learning algorithm based on the training data to obtain a pairing prediction model, wherein the pairing prediction model is used to predict a current pairing combination based on the previous Y pairs of pairing combinations. The wireless optical encryption communication method using vortex optical perturbation as described in claim 3 further includes, after step (C), a step (I), wherein the transmitting end control unit predicts a predicted encryption pairing combination corresponding to the first Y groups of encryption pairing combinations based on the Y groups of encryption pairing combinations generated by the first 1 to Y steps (C) using the pairing prediction model. The wireless optical encryption communication method using vortex optical perturbation as described in claim 4 further comprises the following steps after step (I): (J) the transmitting end control unit compares the encryption pairing combination generated by step (C) with the predicted encryption pairing combination, and updates a predicted accuracy rate according to the comparison result; (K) the transmitting end control unit determines whether the encryption pairing combination generated by step (C) has a risk of decryption according to the predicted accuracy rate; and (L) when the transmitting end control unit determines that there is a risk of decryption, the transmitting end control unit changes the set of control parameters and returns to step (C). In the wireless optical encryption communication method using vortex optical perturbation as described in claim 1, in step (B), the vortex optical encoding unit can be a liquid crystal spatial light modulator. A wireless optical encryption communication method using eddy-optic perturbation is implemented by a receiving-end wireless optical communication device, the receiving-end wireless optical communication device is communicatively connected to a transmitting-end wireless optical communication device, and includes a data recovery unit, an optical demultiplexing unit, an eddy-optic decoding unit connected to the optical demultiplexing unit, and an interface connected to the eddy-optic decoding unit and having N input ports and N output ports. A receiving end wavelength selection switch unit, a receiving end control unit connected to the vortex optical decoding unit and the receiving end wavelength selection switch unit, and a demodulation unit having N demodulators and connected to the data recovery unit and the receiving end wavelength selection switch unit, the N demodulators are respectively connected to the N output terminals of the receiving end wavelength selection switch unit, the method comprises the following steps: (A) The optical demultiplexing unit demultiplexes the optical multiplexed output signal to generate the N sets of optical demultiplexing signals and output them to the eddy-optic decoding unit; (B) The receiving end control unit generates N decoded orbital angular momentum topology load numbers according to the N encoded orbital angular momentum topology load numbers transmitted by the transmitting end control unit, and transmits them to the eddy-optic decoding unit; (C) The eddy-optic decoding unit decodes the N sets of optical demultiplexing signals into N Gaussian light signals with zero orbital angular momentum according to the N decoded orbital angular momentum topology load numbers, and outputs them to the receiving end wavelength selection switch unit; (D) The receiving end control unit generates an encryption pairing combination using a chaotic random non-repetitive permutation algorithm according to the set of control parameters transmitted by the transmitting end control unit, and generates a decryption pairing combination according to the encryption pairing combination, and transmits the decryption pairing combination to the receiving end wavelength selection switch unit, wherein the decryption pairing combination is used to indicate each input end of the receiving end wavelength selection switch unit and its corresponding output end; (E) For each input end of the receiving end wavelength selection switch unit, when the input end receives an input Gaussian light signal corresponding to one of the N Gaussian light signals from the vortex optical decoding unit, the corresponding input Gaussian light signal is output to the output end of the receiving end wavelength selection switch unit corresponding to the input end according to the decryption pairing combination; (F) For each demodulator, the demodulator demodulates the Gaussian light signal output from the output end of the connected receiving end wavelength selection switch unit to generate a corresponding data bit data, and outputs it to the data restoration unit; and (G) the data restoration unit restores each data bit data to generate N source data. The wireless optical encryption communication method using vortex optical perturbation as described in claim 7, wherein step (D) includes the following sub-steps: (D-1) the receiving end control unit generates a random time sequence of length N using a chaotic equation according to the set of control parameters; (D-2) the receiving end control unit maps each value in the random time sequence to a corresponding positive integer sequence; (D-3) the receiving end control unit converts the N positive integer sequences into a permutation matrix to generate the same encryption pairing combination as that generated by the transmitting end wireless optical communication device; and (D-4) The receiving end control unit generates a decryption pairing combination according to the encryption pairing combination, and transmits the decryption pairing combination to the receiving end wavelength selection switch unit, wherein the decryption pairing combination is used to indicate each input end of the receiving end wavelength selection switch unit and its corresponding output end.

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