JP7451223B2 - Optical communication system, transmitting side device, receiving side device, and optical communication method - Google Patents

Description

The present embodiment relates to an optical communication system, a transmitting side device, a receiving side device, and an optical communication method.

In optical communication systems, there is a method of transmitting and receiving data with an error correction code using carrier light with fluctuations that cause bit errors, as a technique that takes into consideration safety against leakage of transmitted data. Although this method is relatively simple, there is a problem that error correction takes time and transmission efficiency decreases. As another technique, countermeasures to prevent unauthorized reading of the amount of phase modulation using quantum encryption technology have been proposed, but the increase in error rate due to quantum encryption necessitates the use of error correction codes, which still reduces transmission efficiency. I fall. Additionally, a countermeasure using wavelength control of a wavelength tunable laser array has also been proposed. According to this proposal, transmission efficiency is high, but communication confidentiality is low. Additionally, systems have been proposed in which individual data values are transmitted in association with a plurality of wavelengths, and a data set including a plurality of data items is received and analyzed to be encrypted. According to this proposal, the transmission efficiency is good, but since it requires a multi-wavelength laser, it is expensive, it is difficult to miniaturize, and the optical wavelength is fixed, so the transmission is carried out by multivariate analysis. Data may be identified.

Japanese Patent Application Publication No. 2010-035072 Japanese Patent Application Publication No. 2007-251998 JP2015-207738A Japanese Patent Application Publication No. 2018-98762

Temperature-independent, wavelength-tunable laser using micromachine structure, Masatoshi Nakahama, Tokyo Institute of Technology, http://www.fbi-award.jp/sentan/jusyou/2014/1.pdf

As described above, it is difficult to simultaneously satisfy cost, transmission efficiency, miniaturization, and confidentiality using conventional methods for ensuring safety in optical communication systems.

The present embodiment has been developed in view of the above-mentioned problems, and is an optical communication system in which it is difficult to distinguish optical wavelengths, difficult to decipher due to leakage in optical transmission paths, and excellent in cost, transmission efficiency, miniaturization, and confidentiality. The object of the present invention is to provide a transmitting side device, a receiving side device, and an optical communication method.

In order to solve the above problems, the optical communication system according to the present embodiment includes a transmitting side device that encodes and encrypts transmission data, converts it into an optical signal, and outputs it to an optical communication path, and and a receiving device that receives an optical signal transmitted from the transmitting device via a receiver, decrypts the encryption, and decodes the encoded transmission data. The transmitting side device controls the wavelength of the optical signal output to the optical communication path based on the selected encryption pattern for the encryption, and the receiving side device controls the wavelength of the optical signal output to the optical communication path based on the selected encryption pattern for the encryption. A change in the wavelength of the optical signal from the transmitting device is detected, the encryption pattern is verified, and the encryption is decoded using the verified encryption pattern.

FIG. 1 is a block diagram showing the configuration of an optical communication system according to an embodiment. FIG. 2 is a diagram showing an example of information processing used in the embodiment. FIG. 3 is a diagram showing an encryption code table of the information processing example shown in FIG. 2. FIG. 4 is a waveform diagram showing an example of variation in transmission wavelength used in the embodiment. FIG. 5 is a waveform diagram showing an example of variation in transmission strength used in the embodiment. FIG. 6 is a waveform diagram showing the transmission characteristics of two wavelength filters used in the embodiment. FIG. 7 is a characteristic diagram showing difference information for wavelength detection obtained by O/E converting the outputs of two wavelength filters used in the embodiment. FIG. 8 is a waveform diagram showing the O/E conversion results of the outputs of two wavelength filters used in the embodiment. FIG. 9 is a characteristic diagram illustrating the relationship between wavelength fluctuation and the number of consecutive same codes used in the embodiment. FIG. 10 is a waveform diagram showing the results of wavelength prediction performed according to the switching cycle of the encryption code used in the embodiment. FIG. 11 is a waveform diagram showing the error between the predicted value and the actual measured value of the wavelength used in the embodiment. FIG. 12 is a diagram showing an example of information processing of a receiving system used in the embodiment. FIG. 13 is a block diagram showing an example of a system in which system 1 and system 2 are connected via an optical communication path as a modification of the embodiment. FIG. 14 is a block diagram showing the configuration of a multi-wavelength optical communication system as a modification of the embodiment.

First, an overview of the optical communication system according to the embodiment will be explained.

This embodiment proposes a system with high encryption performance by performing multidimensional modulation using "light wavelength/light intensity" (physical layer) and "data processing (data link layer)." In other words, on the regular transmitter side, in addition to the optical wavelength shift caused by heat that depends on the communication data, a small amount of optical wavelength shift is performed by controlling the temperature of the device from the outside, and this optical wavelength shift causes the encrypted information (encrypted code). On the other hand, on the regular receiving side, precise wavelength measurement is performed using a light intensity and a wavelength filter, and the amount of wavelength fluctuation is predicted according to the received intensity. Encrypted information (encrypted code) is estimated from the amount of deviation between the predicted value and the actual measured value of wavelength fluctuation, and the original communication data is decoded through data processing. In this way, the present embodiment uses "multidimensional modulation" and "minor wavelength fluctuations" to complicate the transmission of encrypted information, making it difficult for third parties to decode the communication information. There are characteristics.

Embodiments will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an optical communication system according to an embodiment. In FIG. 1, the optical communication system includes a transmitting side device 100 and a receiving side device 200, which are optically connected through an optical communication path.

In the sending device 100, transmission data is encrypted with a predetermined transmission code by a transmission code encoder 101, and then code-converted by a code converter 102 according to a designated pattern. The code-converted transmission data is current-amplified by a current amplifier 103, and then converted from an electrical signal to an optical signal by an E/O (electrical/optical) converter 104 using an optical device such as a semiconductor laser. This optical signal is subjected to a specified amount of attenuation processing by an optional variable attenuator 105 as required, and then distributed to an external system and an internal system by a distributor 106.

On the other hand, the disturbance measuring device 107 measures the outside temperature, which is a disturbance to the optical transmission. The outside temperature measurement result is sent to the temperature control pattern selector 108. This temperature control pattern selector 108 selects a temperature control pattern corresponding to the measurement result of the outside air temperature, and controls the temperature of the temperature controller 109 attached to the E/O converter 104 using the selected temperature control pattern. , shifts the wavelength of the optical signal generated by the E/O converter 104. Furthermore, in order to improve the confidentiality of encryption, the temperature control pattern of the temperature control pattern selector 108 is selected and designated by the pattern setting signal through the encryption pattern selector 110, and the selected pattern information is sent to the code converter 102, and the code Embed in transformation.

However, disturbances caused by outside temperature are difficult to see in a short period of time, and correction is required for long-term transmission. Therefore, disturbance correction may be made optional and added when there is a request for long-term transmission.

The optical signal distributed to the internal system by the distributor 106 is further divided into two parts by a distributor 111, one for intensity detection and one for wavelength detection, and is input to wavelength filters 112 and 113, respectively. The centers of the passbands of the wavelength filters 112 and 113 are set above and below the center of the transmission band, respectively, and the passing light is converted into an electrical signal by O/E (optical/electrical) converters 114 and 115, respectively, to remove the disturbance. The signal is sent to a corrector 116. The disturbance corrector 116 detects, from the electrical signals obtained by the O/E converters 114 and 115, the amount of optical wavelength shift and the amount of change in optical intensity of the optical signal caused by the disturbance (outside temperature). The detected light wavelength shift amount is corrected by temperature control in E/O conversion through the temperature control pattern selector 108, and the light intensity change amount is corrected by the variable attenuator 105.

Note that the temperature control pattern selector 108 is provided with the measurement result of the disturbance measuring device 107 and the correction value of the disturbance corrector 116, but either one or both may be provided.

In the receiving device 200, the optical signal transmitted from the transmitting device 100 is divided into two systems by a distributor 201, one of which is converted into an electrical signal by an O/E converter 202, and an optical signal is transmitted by an intensity detector 203. The amplitude of the intensity is detected. The detection result is sent to the collation device 204 as received data. When the verification device 204 obtains regular authentication through verification described later, the received data is subjected to inverse encoding conversion in the code inverse converter 205 and then sent to the transmission code decoder 206 . Here, the optical signal distributed by input divider 201 is further divided into two by divider 207 and sent to wavelength filters 208 and 209, respectively. The centers of the passbands of the wavelength filters 208 and 209 are set above and below the center of the transmission band, respectively, and the passing light is converted into electrical signals by O/E (optical/electrical) converters 210 and 211, respectively, and converted into wavelengths. The signal is sent to a detector 212. The wavelength detector 212 detects a pattern of wavelength change of the transmitted optical signal from the two input electric signals, sends this pattern to the collation device 204, and collates it with the output of the intensity detector 203. If a match is detected in the comparison, the matching pattern is sent to the encryption pattern selector 213 to select the corresponding encryption pattern. The selected encryption pattern is sent to the transmission code decoder 206, and the received data from the code inverse converter 205 is decrypted using the encryption pattern.

The processing operation of the optical communication system having the above configuration will be explained below.

First, the processing of the sending device 100 will be explained. In the transmitting device 100, in an optical device such as a semiconductor laser used in the E/O converter 104, an increase or decrease in the number of oscillation modes or a fluctuation in the transmission wavelength occurs due to modulation due to a change in the transmission code or fluctuations in the device ambient temperature. do. In high-density wavelength division multiplexing transmission, mutual interference occurs due to optical wavelength fluctuations, so many correction methods have been studied to ensure stable transmission of the transmission frequency. In this embodiment, we propose a method that not only stabilizes the optical wavelength but also incorporates cryptographic information into the optical wavelength shift itself.

The main factors that cause optical wavelength shifts depend on the current carrier effect and temperature injected into optical devices such as semiconductor lasers. The temperature of an optical device is determined by the ``internal heat generation amount that causes a transient temperature change in the pulse-driven laser depending on the transmission code pattern'' and the ``external heat generation amount (heat absorption amount) determined by the heat conduction of the surrounding structure and external temperature control.'' )”. Here, we focus on external temperature control and shift the transmission wavelength by changing the temperature of the optical device using a pattern different from the transmission code according to the encryption information (encryption code). The equipment on the official receiving side measures the optical intensity and the amount of shift in optical wavelength. The predicted value of the optical wavelength can be determined from the received light intensity, and by deciphering the slight deviation from the actual observed value, the encrypted information (encrypted code) can be calculated. The received signal can be demodulated using this encryption information (encryption code) to obtain regular data.

With this method, even if an eavesdropper can detect light leakage from the optical communication path, it is difficult to secure a sufficient S/N ratio to detect wavelength fluctuations, making it difficult to extract the encrypted information (encrypted code). Therefore, the confidentiality is extremely high. Furthermore, if the light intensity is reduced on the transmitting side so as to reach the minimum reception sensitivity of the authorized receiving side, it becomes even more physically difficult to decipher the encrypted information (encrypted code).

The operation details of the specific encryption mechanism will be explained. First, the processing of the sending device 100 will be explained with reference to FIGS. 2 to 5. Here, FIG. 2 is a diagram showing an example of information processing, FIG. 3 is a diagram showing an encryption code table of the information processing example shown in FIG. 2, FIG. 4 is a waveform diagram showing an example of variation in transmission wavelength, and FIG. 5 is a diagram showing transmission strength FIG.

In the information processing example shown in FIG. 2, the bit sequence of the transmission data is "55aa55aa...". A pattern table is selected and encrypted based on an encryption code arbitrarily set for the code. Here, for easy explanation, the encryption codes are limited to three types (code 1, code 2, and code 3), as shown in FIG. Then, the number of consecutive identical codes is limited in order to make it easier to predict wavelength information. An example of a mechanism for limiting the number of consecutive same codes is 8-bit/10-bit conversion (code length conversion, which is a type of high-speed serial transfer method). By limiting the number of consecutive same signs, the width of the wavelength shift amount can be reduced. Although transmission efficiency decreases, the smaller the amount of optical wavelength shift, the more difficult it is for third parties to detect optical wavelength fluctuations.

Thereafter, the current is amplified based on the transmission code, and E/O conversion is performed using a laser or the like. At the same time, temperature control is performed according to the encryption code to cause minute wavelength fluctuations. For example, it is assumed that "code 1 is on the lower wavelength side, code 2 is the same as it is, and code 3 is a higher wavelength shift." Then, the light wavelength and light intensity after E/O conversion have characteristics as shown in FIGS. 4 and 5, for example.

Next, the processing of the receiving device 200 will be explained with reference to FIGS. 6 to 12. Here, FIG. 6 is a waveform diagram showing the transmission characteristics of the two wavelength filters 208 and 209, and FIG. 7 is a characteristic diagram showing difference information for wavelength detection obtained by O/E converting the outputs of the two wavelength filters 208 and 209. Fig. 8 is a waveform diagram showing the O/E conversion results of the outputs of the two wavelength filters 208 and 209, Fig. 9 is a characteristic diagram showing the relationship between wavelength fluctuation and the number of consecutive same codes as an image, and Fig. 10 is an encryption FIG. 11 is a waveform diagram showing the results of wavelength prediction performed according to the code switching cycle, FIG. 11 is a waveform diagram showing the error between the predicted wavelength value and the actual measured value, and FIG. 12 is a diagram showing an example of information processing on the receiving side.

In the receiving device 200, an optical signal sent from the transmitting device 100 via an optical communication path is input to a distributor 201, and the optical signal is separated into intensity detection and wavelength detection for measurement. When the degree of optical modulation of the received light is small, binary determination of weak light is performed using a moving average threshold value or the like. Since clock recovery can be easily performed by limiting the number of consecutive same codes, the interval for wavelength prediction is determined based on the clock. Two wavelength filters 208 and 209 are used to accurately detect the optical wavelength. Any filter may be used as long as it has wavelength-gain characteristics. For example, a band illumination filter having wavelength-gain characteristics as shown in FIG. 6 can be used. Note that some filters have characteristics in which the vertical and horizontal axes in FIG. 6 change.

When two wavelength filters 208 and 209 are used, the wavelength can be determined from the difference information of O/E conversion for wavelength detection, as shown in FIG. As a further development, the sum information for wavelength detection can be replaced with light intensity information. Information after O/E conversion is shown in FIG.

Here, when the external temperature on the transmitting side is constant, FIG. 9 shows an image in which the relationship between wavelength fluctuation and the number of consecutive same signs is approximated to a first-order lag system. When a highly stable laser such as a DFB (Distributed Feedback) laser is used, the change in refractive index due to temperature is slow, so the amount of wavelength fluctuation is small. The switching period of the encryption code is set as information known in advance to each of the transmitting side device 100 and the receiving side device 200 in accordance with the heat conduction time constant specific to the device.

The characteristics shown in FIG. 9 are specific to the transmitting device. The receiving device 200 also holds this information in advance as known information. The receiving device 200 performs wavelength prediction according to the switching cycle of the encryption code. The results of wavelength prediction are shown in FIG. Here, an example is shown in which the prediction is repeated while the initial value of the wavelength prediction is updated to the actual value one by one for each length of the transmission code.

Next, FIG. 11 shows the error between the predicted value and the actual measured value. The encryption code can be determined from this error value. Then, the received binary data is decoded using the pattern table shown in FIG. 12 prepared in advance on the receiving side to obtain the original transmission data.

As described above, according to the optical communication system with the above configuration, multidimensional modulation is performed using "light wavelength/light intensity" (physical layer) and "data processing (data link layer)". Therefore, it is possible to construct a system with higher encryption performance. In other words, in addition to the optical wavelength shift caused by heat that depends on the communication data of the authorized sender, a small amount of optical wavelength shift is performed by controlling the temperature of the optical device from the outside, and encryption information (encryption code) is superimposed. . On the other hand, on the regular receiving side, optical intensity detection and precise wavelength measurement using a wavelength filter are performed, and the amount of wavelength fluctuation is predicted according to the received intensity. Encrypted information (encrypted code) is estimated from the amount of deviation between the predicted value and the actual measured value of wavelength fluctuation, and the original communication data is decoded through data processing. As described above, in this embodiment, the transmission of encrypted information is complicated by "multidimensional modulation" and "minor wavelength fluctuations", and even if leaked information is obtained from the optical communication channel, Since the amount of leaked light is extremely weak, it is extremely difficult to identify multidimensional modulation and minute wavelength fluctuations and obtain encrypted information. Therefore, compared to conventional systems, communication information is less likely to be deciphered by a third party, which is an excellent effect.

Note that the configuration of the above embodiment can be modified in various ways as described below.
(1) Change of wavelength variable structure In this embodiment, temperature adjustment is used for wavelength control. The wavelength changes as the optical path length and refractive index change due to temperature rise, but other wavelength control methods can also be applied. For example, changing the resonator length using a micromachine (MEMS: Micro Electro Mechanical Systems) for adjusting the oscillation wavelength may be used. Further, regarding the amount of wavelength variation, time management of the amount of wavelength variation may be performed by varying the control amount. (See Non-Patent Document 1)
(2) Variation of transmitted light intensity In order to improve robustness against information leakage, a variable attenuator 105 for optical signals may be used as an option on the transmitting side to lower the transmission gain. When two or more devices are capable of bidirectional communication, the light intensity of the transmitted light is set near the minimum receiving sensitivity so that the decoding rate can be lowered. This setting may include a handshake function that can find the minimum reception sensitivity while varying the light intensity and wavelength. Using this function, it is preferable to adjust the transmission gain within a range that satisfies [reception gain = optical transmission gain - transmission line loss (fiber loss + connector loss + wavelength filter sensitivity loss) > minimum reception sensitivity].

(3) Change in wavelength measurement For the wavelength filter, use one that has frequency-attenuation characteristics, such as a multilayer filter, FBG (Fiber Bragg Grating), birefringence filter, or Fabry-Perot etalon. Since the optical intensity and optical wavelength need only be determined, the position and distribution ratio of the optical distributor on the receiving side may be changed arbitrarily.

(4) Changing the wavelength modulation type As shown in Figure 13, when system 1 and system 2 are connected via an optical communication channel and each system is enabled to receive time information T1 from the GPS satellite, the system After synchronizing the time, time information is inserted into the wavelength information instead of the encryption code. In this way, by comparing the data arrival time and the time information included in that data, it is possible to determine the delay of a repeater installed by a third party in the middle of the optical transmission line, and discover failures caused by the regenerative repeating method. can do. in particular,
Safety: Arrival time T2 - time information T1 ≒ transmission time
Danger: Arrival time T3 - time information T1 ≠ transmission time
It is a good idea to set up judgment criteria like this.

(5) Suppression of disturbance components Outside temperature is one of the disturbance components in wavelength and light intensity. In the disturbance measuring device 107, the amount of disturbance is measured with a thermistor or the like, and is inputted to the temperature control pattern selector 108, and wavelength fluctuations and output fluctuations that become disturbances are suppressed by feedback control. Alternatively, the disturbance component can be canceled by returning and receiving a part of the transmitted light by the distributor 106.

(6) Multi-value encryption code In this embodiment, three types of encryption codes are used, but it is also possible to make the encryption code multi-value. Furthermore, information can also be included in the slope of wavelength fluctuation (amount of minute fluctuation=difference δ). Further, the light intensity can also be multivalued. This multivalue conversion does not necessarily need to ensure linearity, and for example, numerical conversion by projection of an exponential function system may be performed.

(7) Error correction and error detection By incorporating information such as Reed-Solomon and CRC (Cyclic Redundancy Check) into the wavelength domain instead of an encryption code, even in low bit rate signal transmission, wavelength The reliability of data transmission can be improved from the information.

(8) Temperature control of wavelength filters In order to improve the robustness of the wavelength filters 208 and 209 for temperature-dependent wavelength detection (suppression of disturbance components due to the state of the surrounding environment), the ambient temperature of the wavelength filters 208 and 209 is kept at a constant temperature. It is possible to control it. For example, the two filters 208 and 209 may each be provided with a temperature detection element and a temperature adjustment element.

(9) Multiple wavelengths Although it goes against the trend of system cost reduction and miniaturization, it is also possible to consider an optical communication system that employs an encryption method based on multi-dimensional modulation using multiple wavelength light sources. FIG. 14 shows the configuration of an optical communication system with multiple wavelengths. This system distributes transmission data to transmission system 1 and transmission system 2 in the transmission side device, combines optical signals that have been multidimensionally encrypted at different wavelengths using a coupler, and transmits the data via an optical communication path. Send to receiving device. In the receiving side device, the optical signal from the optical communication path is distributed to the receiving system 1 and the receiving system 2 by a distributor, and the optical signals of the wavelengths assigned to each are received and the received data is decoded. Furthermore, it analyzes the received data, performs machine learning, and makes inferences from the learning results.

According to the above configuration, since the number of dimensions is further increased in each of the transmission systems 1 and 2, it can be used for simultaneous combined transmission and redundant transmission. Since there are many multidimensional parameters in the receiving side device, a method can be considered in which parameters for suppressing disturbance components are learned at the initial stage of communication, and then numerical judgments are made based on inference. Another possibility is to periodically update the encryption code on the sending side and have the receiving side relearn the Sync code so that it can be easily detected.

In addition, the present invention is not limited to the above-described embodiments as they are, and in the implementation stage, the constituent elements can be modified and embodied without departing from the gist of the present invention. Moreover, various inventions can be formed by appropriately combining the plurality of components disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiments. Furthermore, components from different embodiments may be combined as appropriate.

100... Transmission side device, 101... Transmission code encoder, 102... Code converter, 103... Current amplifier, 104... E/O (electrical/optical) converter, 105... Variable attenuator, 106... Distributor, 107 ... Disturbance measurement device, 108 ... Temperature control pattern selector, 109 ... Temperature controller, 110 ... Code pattern selector, 111 ... Distributor, 112, 113 ... Wavelength filter, 114, 115 ... O/E (optical/electrical) Converter, 116...disturbance corrector,
200... Receiving side device, 201... Distributor, 202... O/E converter, 203... Intensity detector, 204... Collator, 205... Code inverse converter, 206... Transmission code decoder, 207... Distributor, 208 , 209...wavelength filter, 210, 211...O/E (optical/electrical) converter, 212...wavelength detector, 213...cipher pattern selector.

Claims (9)

a transmission side device that encrypts transmission data with a predetermined transmission code, converts it into an optical signal, and outputs it to an optical communication path;
a receiving device that receives an optical signal output from the transmitting device via the optical communication path, converts it into an electrical signal, decrypts the electrical signal, and outputs legitimate transmission data;
Equipped with
The transmitting device includes:
transmission code encryption means for encrypting the transmission data with a predetermined transmission code;
code conversion means for performing code conversion according to a specified control pattern on the transmission data encrypted with the transmission code;
an electrical/optical converter that converts the amplitude of the electrical quantity of the code-converted transmission data into the amplitude of the optical intensity of an optical signal by an electrical/optical conversion device, and outputs the converted signal to the optical communication path;
a sender-side cryptographic information selection means for selecting arbitrary cryptographic information from a plurality of cryptographic information;
control pattern selection means for selecting a control pattern corresponding to the cryptographic information selected by the transmitting side cryptographic information selection means and outputting the selected control pattern to the code conversion means as the designated control pattern;
wavelength control means for shifting the wavelength of the optical signal according to the control pattern selected by the control pattern selection means;
Equipped with
The receiving device includes:
light intensity detection means for converting an optical signal transmitted via the optical communication path into an electrical signal and detecting an amplitude change in the light intensity of the optical signal as received data;
wavelength detection means for inputting an optical signal transmitted via the optical communication path and detecting a change in wavelength;
collating means for collating a pattern of amplitude changes in the light intensity of the optical signal detected by the light intensity detecting means and a pattern of wavelength changes detected by the wavelength detecting means to detect a match between the two patterns; ,
Receiving-side cryptographic information selection means for selecting cryptographic information corresponding to the detected pattern from the plurality of cryptographic information when a pattern match is detected by the matching;
code inverse conversion means that performs code inverse conversion on the received data detected by the light intensity detection means according to the pattern in which the match is detected;
The received data subjected to code inverse conversion by the code inverse conversion means is input, and the transmission data is decrypted based on the encryption information selected by the receiving side encryption information selection means, and is converted into regular transmission data. Output encryption/decryption means and
An optical communication system equipped with a transmission side device that encrypts transmission data with a predetermined transmission code, converts it into an optical signal, and outputs it to an optical communication path;
a receiving device that receives an optical signal output from the transmitting device via the optical communication path, converts it into an electrical signal, decrypts the electrical signal, and outputs legitimate transmission data;
Used in optical communication systems equipped with
transmission code encryption means for encrypting the transmission data with a predetermined transmission code;
code conversion means for performing code conversion on the transmission data encrypted with the transmission code according to a specified control pattern;
an electrical/optical converter that converts the amplitude of the electrical quantity of the code-converted transmission data into the amplitude of the optical intensity of an optical signal by an electrical/optical conversion device, and outputs the converted signal to the optical communication path;
a sender-side cryptographic information selection means for selecting arbitrary cryptographic information from a plurality of cryptographic information;
control pattern selection means for selecting a control pattern corresponding to the cryptographic information selected by the transmitting side cryptographic information selection means and outputting the selected control pattern to the code conversion means as the designated control pattern;
wavelength control means for shifting the wavelength of the optical signal according to the control pattern selected by the control pattern selection means;
A transmitting side device of an optical communication system comprising : 3. The transmission side apparatus of an optical communication system according to claim 2, wherein said wavelength control means controls the temperature of an electric/optical conversion device used in said electric/optical conversion means. 3. The transmission side device of an optical communication system according to claim 2, wherein the wavelength control means controls the length of a resonator for adjusting the oscillation wavelength of the optical signal used in the electric/optical conversion means. 3. The transmission side device of an optical communication system according to claim 2, wherein said wavelength control means includes information on a change in said wavelength in a slope. 3. The transmission side device of an optical communication system according to claim 2, wherein the electrical/optical conversion means further includes a variable attenuator that attenuates the optical signal output to the optical communication path in accordance with a minimum receiving sensitivity. a transmission side device that encrypts transmission data with a predetermined transmission code, converts it into an optical signal, and outputs it to an optical communication path;
a receiving device that receives an optical signal output from the transmitting device via the optical communication path, converts it into an electrical signal, decrypts the electrical signal, and outputs legitimate transmission data;
Used in optical communication systems equipped with
The transmitting device,
transmission code encryption means for encrypting the transmission data with a predetermined transmission code;
code conversion means for performing code conversion on the transmission data encrypted with the transmission code according to a specified control pattern;
an electrical/optical converter that converts the amplitude of the electrical quantity of the code-converted transmission data into the amplitude of the optical intensity of an optical signal by an electrical/optical conversion device, and outputs the converted signal to the optical communication path;
a sender-side cryptographic information selection means for selecting arbitrary cryptographic information from a plurality of cryptographic information;
control pattern selection means for selecting a control pattern corresponding to the cryptographic information selected by the transmitting side cryptographic information selection means and outputting the selected control pattern to the code conversion means as the designated control pattern;
wavelength control means for shifting the wavelength of the optical signal according to the control pattern selected by the control pattern selection means;
When preparing
light intensity detection means for converting an optical signal transmitted via the optical communication path into an electrical signal and detecting an amplitude change in the light intensity of the optical signal as received data;
wavelength detection means for inputting an optical signal transmitted via the optical communication path and detecting a change in wavelength;
collating means for collating a pattern of amplitude changes in the light intensity of the optical signal detected by the light intensity detecting means and a pattern of wavelength changes detected by the wavelength detecting means to detect a match between the two patterns; ,
Receiving-side cryptographic information selection means for selecting cryptographic information corresponding to the detected pattern from the plurality of cryptographic information when a pattern match is detected by the matching;
code inverse conversion means that performs code inverse conversion on the received data detected by the light intensity detection means according to the pattern in which the match is detected;
The received data subjected to code inverse conversion by the code inverse conversion means is input, and the transmission data is decrypted based on the encryption information selected by the receiving side encryption information selection means and becomes regular transmission data. Output encryption/decryption means and
A receiving side device of an optical communication system comprising : When the transmitting side device employs a multi-type multidimensional modulation encryption method using a plurality of wavelength light sources, the optical signal from the optical communication path is distributed to a plurality of receiving systems by a distribution means and assigned to each. 8. The receiving side device of an optical communication system according to claim 7, wherein the receiving side device of an optical communication system is configured to receive an optical signal of a given wavelength and decode the received data, further analyze the received data and perform machine learning, and infer transmission data from the learning result. . On the transmitting side, after encrypting the transmitted data with a predetermined transmission code, it is converted into an optical signal and output to an optical communication channel.
The receiving side receives the optical signal output from the transmitting side device via the optical communication path, converts it into an electrical signal, decrypts the encryption of the electrical signal, and outputs regular transmission data. ,
The sending side is
encrypting the transmission data with a predetermined transmission code;
The transmission data encrypted with the transmission code is subjected to code conversion according to a specified control pattern,
converting the amplitude of the electrical quantity of the transmission data subjected to the code conversion into the amplitude of the optical intensity of the optical signal by an electrical/optical conversion device, and outputting the converted signal to the optical communication channel;
Select any encryption information from multiple encryption information,
selecting a control pattern corresponding to the selected cryptographic information, and using the selected control pattern as the designated control pattern for the code conversion;
shifting the wavelength of the optical signal according to a control pattern corresponding to the selected cryptographic information;
The receiving side is
converting an optical signal transmitted via the optical communication path into an electrical signal, detecting an amplitude change in the optical intensity of the optical signal as received data,
inputting an optical signal transmitted via the optical communication path and detecting a change in its wavelength;
comparing a pattern of amplitude changes in the light intensity of the optical signal with a pattern of wavelength changes of the optical signal to detect a match between the two patterns;
When a pattern match is detected by the matching, selecting cryptographic information corresponding to the detected pattern from the plurality of cryptographic information;
performing code inverse conversion on the detected received data according to the pattern in which the match was detected;
An optical communication method , wherein the received data subjected to the code inverse conversion is input, the transmission data is decrypted based on the selected encryption information, and the transmitted data is output as regular transmission data.

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