Optical frequency hopping communication system and method

Abstract

The optical frequency hopping communication system provided by the disclosure is applied to the field of optical communication and comprises a sending end, a key group, an optical signal, a plurality of wavelengths, a target path, a plurality of wavelength broadcast distribution, a plurality of frequency hopping sequences, a frequency hopping sequence, a modulation signal, a transmission signal forming module, a coupling generation, a transmission fiber, a receiving end, a same key group, a decoding, and an original data stream sequence.

Description

Technical Field

[0001] This disclosure relates to the field of optical communications, and more specifically, to an optical frequency hopping communication system and method. Background Technology

[0002] Optical frequency-hopping secure transmission technology was initially conceived from frequency-hopping techniques in wireless digital communication. Frequency-hopping technology refers to the periodic hopping of the carrier frequency of the transmitted signal under the control of a pseudo-random sequence. As a type of spread spectrum technology, it expands the spectrum of the information to be transmitted over a large bandwidth. The receiving end typically uses correlation reception to compress the bandwidth and recover the original narrowband signal. Simultaneously, due to the spectrum expansion, frequency-hopping technology also possesses many advantages of spread spectrum systems, such as better anti-interference and anti-interception capabilities, as well as better anti-fading and anti-multipath capabilities.

[0003] The frequency hopping rule of a carrier in the time domain is called a frequency hopping pattern. N possible carrier frequencies constitute the hopping set {f1, f2, f3, … , fN}, and the channel of each frequency occupies a small spectral region B within the entire channel bandwidth W. This hopping bandwidth B is sufficient to contain most of the energy of the signal pulse. Generally, W ≥ NB. From the time domain perspective, the time interval between different hoppings is called the hopping period, and the rate of carrier hopping is the hopping rate. Because the hopping carriers are distributed over a wide bandwidth and controlled by a pseudo-random sequence, they are difficult to track and eavesdrop on. Therefore, researching optical frequency hopping communication security technologies based on different physical principles and realizing different optical frequency hopping communication systems is not only of academic value but also of significant practical importance.

[0004] However, most current optical frequency hopping secure transmission technologies are based on discrete components, which are complex and bulky. Furthermore, the transceiver only has one set of keys, which can lead to the loss of key security if cracked or stolen, thus failing to guarantee communication security. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] This disclosure provides an optical frequency hopping communication system and method, which at least partially solves one of the above-mentioned technical problems.

[0007] (II) Technical Solution

[0008] This disclosure provides an optical frequency hopping communication system, comprising: a transmitter for transmitting signals, wherein the transmitter modulates the optical signal based on a key set to generate multiple frequency hopping sequences, then modulates multiple data stream sequences onto each frequency hopping sequence, and the frequency hopping sequences with modulated signals are coupled into a transmission signal forming module to generate a transmission signal, which is then transmitted through an optical fiber; wherein the key set includes a first key and a second key, and the optical signal contains multiple wavelengths; the transmitter determines a target path based on the first key, and broadcasts and distributes multiple wavelengths in the optical signal transmitted along the target path based on the second key to generate multiple frequency hopping sequences, wherein the wavelength of each frequency hopping sequence changes over time, and the change pattern of the frequency hopping sequence is controlled by the key set; and a receiver for receiving the transmitted signal, decoding the transmitted signal based on the same key set as the transmitter, and recovering the original data stream sequence after conversion by multiple photodetectors.

[0009] Optionally, the transmitting end includes: a first optical switch for determining a target first path based on a first key; wherein the first optical switch includes multiple first paths, each first path corresponding to a first output port; and a first broadcast routing wavelength selection switch array for broadcasting and distributing multiple wavelengths in the optical signal based on a second key to generate a multi-channel frequency hopping sequence; wherein the frequency hopping sequence on the second path generated by the broadcast distribution depends on the second key and the output result of the first target path, that is, the signal wavelength in each second path will change over time, and the change pattern of the frequency hopping sequence signal is controlled by the key group.

[0010] Optionally, the first broadcast routing wavelength selection switch array includes multiple second input ports and multiple second output ports. The second input ports are connected to the first output ports of the first optical switch and are used to receive optical signals transmitted by the first optical switch. The optical signals output from different first output ports correspond to different distribution modes in the first broadcast routing wavelength selection switch array.

[0011] Optionally, the transmitting end further includes: a light source emitting device for transmitting optical signals, wherein the light source emitting device is a multi-channel laser array chip, or a combination of a single-wavelength light source and an optical frequency comb; a data modulation module, composed of multiple modulators, for modulating multiple data stream sequences onto each frequency hopping sequence to generate multi-modulated frequency hopping signals; wherein the data stream sequences loaded on different frequency hopping sequences are different; wherein the multiple modulators are respectively connected to multiple second output ports in the first broadcast routing wavelength selection switch array; a transmission signal forming module, composed of a multi-wavelength optical multiplexer, for multiplexing the frequency hopping sequences with modulated signals to generate a transmission signal; an arbitrary waveform generator for generating multiple data stream sequences and sending the multiple data stream sequences to the multiple modulators respectively; a first pseudo-random code generator, connected to the first optical switch and the first broadcast routing wavelength selection switch array, for obtaining a first key and a second key, and sending the first key and the second key to the first optical switch and the first broadcast routing wavelength selection switch array respectively.

[0012] Optionally, the receiver includes: a second optical switch for determining a target path based on a first key, wherein different target paths correspond to different transmission signal path switching modes; and a second broadcast routing wavelength selection switch array for broadcasting and distributing multiple wavelengths of the received transmission signal based on the second key to recover the frequency hopping sequence.

[0013] Optionally, the receiver further includes: a signal amplifier, used to receive and amplify the transmitted signal strength after transmission through optical fiber to compensate for transmission loss on the optical fiber link, and send the amplified transmitted signal to the second optical switch; a signal restoration module, composed of multiple photodetectors, used to perform photoelectric conversion on the recovered frequency hopping sequence to restore multiple sets of original data stream sequences; and a second pseudo-random code generator, connected to the second optical switch and the second broadcast routing wavelength selection switch array, used to obtain the first key and the second key, and send the first key and the second key to the second optical switch and the second broadcast routing wavelength selection switch array respectively.

[0014] Optionally, the transmitting and receiving ends are connected by discrete devices, or are fabricated based on silicon-based active chips and / or III-V group active chips.

[0015] Optionally, both the first optical switch and the second optical switch are formed by cascading a 1-to-2 optical switch.

[0016] This disclosure also provides an optical frequency hopping communication method, comprising: modulating an optical signal based on a key group to generate multiple frequency hopping sequences; then modulating multiple data stream sequences onto each frequency hopping sequence; coupling the frequency hopping sequences with modulated signals into a transmission signal forming module to generate a transmission signal; and transmitting the transmission signal into an optical fiber for transmission; receiving the transmission signal; decoding the transmission signal based on the same key group as the transmitting end; and recovering the original data stream sequence after conversion by a photodetector; wherein the key group includes a first key and a second key, and the optical signal contains multiple wavelengths; modulating the optical signal based on the key group to generate multiple frequency hopping sequences includes: determining a target path based on the first key; broadcasting and distributing multiple wavelengths in the optical signal transmitted along the target path based on the second key to generate multiple frequency hopping sequences; wherein the wavelength of each frequency hopping sequence changes over time, and the change pattern of the frequency hopping sequence is controlled by the key group.

[0017] Optionally, decoding the transmitted signal based on the same key set as the transmitter includes: determining the target path of the transmitted signal in the second optical switch based on the first key, wherein different target paths correspond to different transmission signal path switching modes; broadcasting and distributing multiple wavelengths of the received transmitted signal based on the second key to recover the frequency hopping sequence; and performing photoelectric conversion on the recovered frequency hopping sequence to restore multiple sets of original data stream sequences.

[0018] (III) Beneficial Effects

[0019] The optical frequency hopping communication system disclosed herein has at least the following beneficial effects:

[0020] This disclosure uses two sets of keys to sequentially regulate the optical signal, thereby achieving frequency hopping of the optical signal, which improves signal security, reduces the risk of key cracking, and effectively avoids leakage of communication content. The key grouping mechanism can effectively improve optical communication security and enhance the anti-interference and anti-interception capabilities of the optical frequency hopping system. Attached Figure Description

[0021] Figure 1 A block diagram of an optical frequency hopping communication system according to an embodiment of the present disclosure is shown schematically;

[0022] Figure 2 The schematic diagram illustrates a structural schematic of an optical frequency hopping communication system according to an embodiment of the present disclosure;

[0023] Figure 3 A flowchart illustrating the optical frequency hopping communication method of this disclosure is shown schematically.

[0024] Figure 4 The diagram illustrates the variation of the frequency hopping sequence over time in the optical frequency hopping communication system of this disclosure.

[0025] [Attached image labels]

[0026] 110 - Light source emitting device; 120 - First optical switch; 130 - First broadcast route wavelength selection switch array; 1401 - Modulator; 1501 - Optical multiplexer; 160 - Arbitrary waveform generator; 170 - First pseudo-random code generator; 200 - Transmission optical fiber; 310 - Signal amplifier; 320 - Second optical switch; 330 - Second broadcast route wavelength selection switch array; 3401 - Photodetector; 350 - Second pseudo-random code generator. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0029] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0030] In the description of this disclosure, it should be understood that the terms "longitudinal", "length", "circumferential", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the subsystem or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.

[0031] Throughout the accompanying drawings, identical elements are represented by the same or similar reference numerals. Conventional structures or constructions have been omitted where they may cause confusion in understanding this disclosure. Furthermore, the shapes, dimensions, and positional relationships of the components in the drawings do not reflect actual size, scale, or actual positional relationships. Additionally, any reference numerals placed between parentheses in the claims should not be construed as limiting the claims.

[0032] Similarly, to simplify this disclosure and aid in understanding one or more of the various aspects of the disclosure, in the above description of exemplary embodiments of the present disclosure, various features of the present disclosure are sometimes grouped together in a single embodiment, figure, or description thereof. The use of terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refers to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present disclosure. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] Figure 1 A block diagram of an optical frequency hopping communication system according to an embodiment of the present disclosure is shown schematically.

[0035] According to an embodiment of this disclosure, the optical frequency hopping communication system includes a transmitter 100, a transmission optical fiber 200, and a receiver 300.

[0036] Transmitter 100 is used to transmit signals. Transmitter 100 modulates the optical signal based on the key group to generate multiple frequency hopping sequences. Then, it modulates multiple data stream sequences onto each frequency hopping sequence, merges the frequency hopping sequences with the modulated signals into the transmission signal forming module, couples them together, generates a transmission signal, and sends the transmission signal into the transmission optical fiber 200 for transmission.

[0037] In some embodiments, the key group includes a first key and a second key, and the optical signal contains multiple wavelengths. By modulating the optical signal based on the key group, a frequency hopping pattern can be generated in the optical signal in time, resulting in a multi-channel frequency hopping sequence.

[0038] The transmitting end determines the target path based on the first key, and broadcasts and distributes multiple wavelengths in the optical signal transmitted along the target path based on the second key, generating multiple frequency hopping sequences. The wavelength of each frequency hopping sequence changes over time, and the change pattern of the frequency hopping sequence is controlled by the key group.

[0039] The transmission fiber 200 is connected to the transmitting end 100 and the receiving end 300 respectively, and is used to receive the transmission signal transmitted by the transmitting end 100 and transmit the received transmission signal to the receiving end 300.

[0040] The receiver 300 is used to receive the transmitted signal and decode the transmitted signal based on the same key group as the transmitter 100, and recover the corresponding data stream sequence after conversion by a photodetector.

[0041] Figure 2 A schematic diagram of the structure of an optical frequency hopping communication system according to an embodiment of the present disclosure is shown.

[0042] like Figure 1 , Figure 2 As shown, the transmitting end of the optical frequency hopping communication system provided in this embodiment includes: a light source transmitting device 110, a first optical switch 120, a first broadcast routing wavelength selection switch array 130, a data modulation module 140, a transmission signal forming module 150, an arbitrary waveform generator 160, and a first pseudo-random code generator 170.

[0043] The light source emitting device 110 is used to emit an optical signal, wherein the optical signal is obtained by combining multiple laser wavelengths. In this embodiment of the present disclosure, the light source emitting device 110 can be a multi-channel laser array chip or instrument that simultaneously outputs multiple laser wavelengths and combines them to obtain an optical signal. It can also be a combination of a single-wavelength light source and an optical frequency comb.

[0044] The first optical switch 120 is used to determine the first path of the target based on the first key.

[0045] In some embodiments, the first optical switch 120 includes a plurality of first paths, each first path corresponding to a first output port, and the first optical switch 120 determines the target transmission path of the optical signal based on the received first key.

[0046] During the transmission of optical signals, at a certain moment in the time domain, there is only one output port that has all the wavelengths of the optical signal. That is, the first optical switch only switches the optical signal path and does not process the wavelengths in the optical signal.

[0047] The first broadcast routing wavelength selection switch array 130 is used to broadcast and distribute multiple wavelengths in the optical signal based on the second key, generating a multi-frequency hopping sequence.

[0048] In some embodiments, the first broadcast routing wavelength selection switch array includes multiple second input ports and multiple second output ports, with different second paths corresponding to different wavelengths, and each second path containing only one wavelength.

[0049] For example, an optical signal may contain four wavelengths: λ1, λ2, λ3, and λ4. These four wavelengths are distributed sequentially to second path 1, second path 2, second path 3, and second path 4. The wavelength in second path 1 is λ1, the wavelength in second path 2 is λ2, and so on.

[0050] The second input port of the first broadcast routing wavelength selector 120 is connected to the first output port of the first optical switch 110, and is used to receive the optical signal transmitted by the first optical switch.

[0051] The optical signal is loaded only on one of the input ports of the first broadcast route optical switch array, while the other input ports are in a suspended state when receiving the optical signal.

[0052] Upon receiving an optical signal, the first broadcast routing wavelength selection switch array distributes the optical signal to multiple paths. The optical signals output from different first output ports correspond to different wavelength distribution modes within the first broadcast routing wavelength selection switch array.

[0053] For example, when the optical signal is transmitted from the first output port 1 to the second input port 1, the corresponding wavelength distribution pattern is: λ1 is distributed to the second path 1, λ2 is distributed to the second path 2, λ3 is distributed to the second path 3, and λ4 is distributed to the second path 4. When the optical signal is transmitted from the first output port 2 to the second input port 2, the corresponding wavelength distribution pattern is: λ1 is distributed to the second path 3, λ2 is distributed to the second path 1, λ3 is distributed to the second path 2, and λ4 is distributed to the second path 4.

[0054] After broadcasting and distributing multiple wavelengths in the optical signal, the internal switch of the first broadcast routing wavelength selector 120 will switch states based on the second key, modulating the wavelength in each second path respectively, so that the frequency hopping sequence in each second path will change over time. The change pattern of the frequency hopping sequence is controlled by the key group, that is, the frequency hopping sequence on the second path generated by the broadcast distribution depends on the second key and the output result of the first target path.

[0055] The data modulation module 140, composed of multiple modulators 1401, is used to modulate multiple data stream sequences onto each frequency hopping sequence to generate multi-modulated frequency hopping sequences. The data stream sequences loaded onto different frequency hopping sequences are different, and the multiple modulators 1401 are respectively connected to multiple second output ports in the first broadcast routing wavelength selection switch array.

[0056] The transmit signal forming module 150 is used to multiplex the frequency hopping sequence with the modulation signal to generate the transmit signal.

[0057] In this embodiment of the disclosure, an optical multiplexer 1501 is used to multiplex the modulated signal, coupling multiple frequency hopping sequences with modulated signals of different wavelengths into a single transmit signal, and transmitting the transmit signal to the transmission optical fiber 200 for transmission.

[0058] The optical multiplexer used in this embodiment is a multi-wavelength optical multiplexer.

[0059] An arbitrary waveform generator 160 is used to generate multiple data stream sequences and send the multiple data stream sequences to multiple modulators for signal modulation.

[0060] The first pseudo-random code generator 170 is connected to the first optical switch and the first broadcast routing wavelength selection switch array, and is used to obtain a preset first key and a second key from the local device, and send the first key and the second key to the first optical switch and the first broadcast routing wavelength selection switch array respectively.

[0061] The receiver 300 of the optical frequency hopping communication system provided in this embodiment includes a signal amplifier 310, a second optical switch 320, a second broadcast routing wavelength selection switch array 330, a signal restoration module 340, and a second pseudo-random code generator 350.

[0062] The signal amplifier 310 is used to receive and amplify the strength of the transmitted signal sent by the transmitter 100 to compensate for the transmission loss on the optical fiber link, and to send the amplified transmitted signal to the second optical switch 320.

[0063] The second optical switch 320 is used to determine the target path based on the first key, wherein the path switching mode of the transmitted signal is different for different target paths.

[0064] In some embodiments, the second optical switch 320 has the same structure as the first optical switch 120, including multiple first paths, each first path corresponding to a first output port, and the second optical switch 320 determines the target transmission path of the transmitted signal based on the first key.

[0065] The second optical switch 320 is connected to the signal amplifier 310 and performs transmission path conversion on the received transmission signal based on the first key, so that the transmission signal is output to the second broadcast routing wavelength selection switch array 330 through the same output port as the optical signal.

[0066] The second broadcast routing wavelength selection switch array 330 is used to broadcast and distribute multiple wavelengths of the received transmitted signal based on the second key pair to restore the original order of the frequency hopping sequence with the modulated signal.

[0067] In some embodiments, the second broadcast routing wavelength selection switch array 330 has the same structure as the first broadcast routing wavelength selection switch array 130, including multiple second input ports and multiple second output ports. The second paths corresponding to different wavelengths are different, and each second path contains only one wavelength.

[0068] The second input port of the second broadcast routing wavelength selector 330 is connected to the first output port of the second optical switch 320, and is used to receive the transmission signal transmitted by the second optical switch.

[0069] The transmitted signal is only loaded onto one of the input ports of the second broadcast route optical switch array, while the other input ports are in a suspended state when receiving the transmitted signal.

[0070] Upon receiving the transmitted signal, the second broadcast routing wavelength selection switch array distributes the transmitted signal to multiple paths. The path switching modes corresponding to the transmitted signals output from different first output ports within the second broadcast routing wavelength selection switch array are different.

[0071] The wavelength distribution mode in the second broadcast routing wavelength selection switch array 330 is the same as the path switching mode in the first broadcast routing wavelength selection switch array 130.

[0072] After wavelength distribution of the transmitted signal, the internal switches of the second broadcast routing wavelength selector 330 switch the state based on the second key and modulate the wavelength in each second path to restore the wavelength in each path to its original state, thus obtaining the modulated signal after multi-path decoding. That is, the frequency hopping sequence of the second broadcast routing wavelength selection switch array on the second path generated by broadcast distribution depends on the path output results of the second key and the second optical switch.

[0073] The signal restoration module 340 is used to perform photoelectric conversion on the recovered frequency hopping sequence with modulation signal in order to restore multiple sets of data stream sequences from the frequency hopping sequence.

[0074] In this embodiment of the disclosure, the signal restoration module consists of multiple photodetectors 3401. Each photodetector 3401 performs photoelectric conversion on a frequency hopping sequence with a modulated signal recovered from one channel to restore the data stream sequence.

[0075] The second pseudo-random code generator 350 is connected to the second optical switch 320 and the second broadcast routing wavelength selection switch array 330. It is used to obtain the first key and the second key from the local device and send the first key and the second key to the second optical switch and the second broadcast routing wavelength selection switch array, respectively, so that the second optical switch and the second broadcast routing wavelength selection switch array can restore the frequency hopping sequence based on the first key and the second key, respectively.

[0076] In some embodiments of this disclosure, both the first optical switch and the second optical switch are cascaded from a 1-to-2 optical switch.

[0077] In this embodiment, the first optical switch, the first broadcast routing wavelength selection switch array, the modulator, and the optical multiplexer are all fabricated on an active integrated transmitter chip. The second optical switch, the second broadcast routing wavelength selection switch array, and the detector are all fabricated on an active integrated receiver chip to improve the system's integration and compactness. The active integrated transmitter chip and the active integrated receiver chip can be fabricated based on monolithic integration with silicon or lithium niobate as the core material, or based on heterogeneous integration or hybrid integration with silicon, silicon dioxide, silicon nitride, indium phosphide, or lithium niobate as the core material.

[0078] This disclosure example uses silicon nanowire optical waveguides based on silicon insulator (SOI) material to fabricate active integrated transmitter chips and active integrated receiver chips. The core layer is made of silicon material with a thickness of 220 nm and a refractive index of 3.4744. The waveguide width is 500 nm. The thermo-optic effect is used to change the phase of the waveguide. A Mach-Zehnder interferometer modulator is fabricated using a reverse PN junction.

[0079] Furthermore, in the embodiments disclosed herein, the active integrated transmitter chip and the light source transmitter device can be packaged in an integrated package, and the active integrated receiver chip can also be packaged in a package, thereby providing a miniaturized optical frequency hopping communication system module.

[0080] The optical frequency-hopping communication system disclosed herein divides signal frequency hopping into two steps. The first step modifies the optical signal data transmission path in the optical switch based on a first key and establishes a connection between the transmission path and the wavelength distribution via a broadcast routing wavelength selection switch array, causing the wavelength distribution method to change depending on the optical switch transmission path. Furthermore, based on wavelength distribution, this disclosure further proposes switching the wavelength on each path based on a second key, causing the wavelength on each path to change in a different mode, thereby obtaining a multi-path frequency-hopping sequence and further improving communication security.

[0081] The optical frequency hopping communication system disclosed herein modulates the signal frequency by setting two keys. Even if one of the keys is cracked or leaked, it will not affect communication security, effectively improving communication security and reducing the risk of communication content leakage.

[0082] Based on the above concept, this disclosure also proposes an optical frequency hopping communication method.

[0083] Figure 3 A flowchart illustrating the optical frequency hopping communication method of this disclosure is shown schematically.

[0084] Figure 4The diagram illustrates the variation of the frequency hopping sequence over time in the optical frequency hopping communication system of this disclosure.

[0085] like Figure 3 As shown, the optical frequency hopping communication method of this embodiment includes operations S310 to S320.

[0086] In operation of S310, the optical signal is modulated based on the key group to generate multiple frequency hopping sequences. Then, multiple data stream sequences are modulated onto each frequency hopping sequence. The frequency hopping sequences with modulation signals are merged into the transmit signal forming module and coupled to generate a transmit signal, which is then sent into the optical fiber for transmission.

[0087] In practice, the key group includes a first key and a second key, and the optical signal contains multiple wavelengths.

[0088] The optical frequency hopping communication method provided in this disclosure determines the target path based on a first key, and broadcasts and distributes multiple wavelengths in the optical signal transmitted along the target path based on a second key to generate multiple frequency hopping sequences. The wavelength of each frequency hopping sequence changes over time, and the change pattern of the frequency hopping sequence is controlled by the key group.

[0089] When operating the S320, it receives the transmitted signal, decodes the transmitted signal based on the same key group as the transmitter, and recovers the original data stream sequence after conversion by a photodetector.

[0090] In some embodiments, decoding the transmitted signal based on the same key set as the transmitter includes: determining the target path of the transmitted signal in a second optical switch based on a first key, wherein different target paths correspond to different transmission signal path switching modes; broadcasting and distributing multiple wavelengths of the received transmitted signal based on a second key to recover the frequency hopping sequence; and performing photoelectric conversion on the recovered frequency hopping sequence to restore multiple sets of original data stream sequences.

[0091] In this embodiment, a four-channel laser array chip is used as the light source emitting device, generating output wavelengths λ1, λ2, λ3, and λ4, respectively. These four wavelengths are combined and coupled into a single optical signal, which is then sent to the active integrated emission chip. The four wavelengths change over time as follows: Figure 4 As shown in part (a) of the document.

[0092] Under the control of the first optical switch, the four wavelengths are switched to one of the input ports of the first broadcast routing wavelength selection switch array at different times. Then, the second key controls the broadcast routing wavelength selection switch array to broadcast and distribute multiple wavelengths in the optical signal, generating multiple frequency hopping sequences. Subsequently, a modulator modulates multiple data stream sequences onto each frequency hopping sequence, resulting in multiple frequency hopping sequences with modulated signals, such as... Figure 4As shown in part (b) of the document.

[0093] Multiple frequency-hopping sequences with modulation signals are multiplexed by an optical multiplexer to generate a transmit signal. The transmit signal is sent into a long-distance transmission optical fiber and then into the input of an amplifier. After amplification, it is coupled into an active integrated receiver chip. The on-chip second optical switch and second broadcast route wavelength selection switch array decode the frequency-hopping sequences with modulation signals using two sets of keys generated by a pseudo-random code generator. The decoded multiple frequency-hopping sequences are then input into multiple detectors to reconstruct the data stream sequence.

[0094] The specific embodiments described above provide a further detailed explanation of the technical solutions of this disclosure. It should be understood that the above descriptions are merely specific embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. An optical frequency hopping communication system, characterized in that, include: The transmitter (100) is used to transmit signals. The transmitter (100) modulates the optical signal based on the key group to generate multiple frequency hopping sequences. Then, multiple data stream sequences are modulated onto each frequency hopping sequence. The frequency hopping sequences with modulation signals are coupled into the transmission signal forming module (150) to generate a transmission signal. The transmission signal is then sent into the transmission optical fiber (200) for transmission. The key group includes a first key and a second key, and the optical signal contains multiple wavelengths. The transmitting end (100) determines the target path based on the first key and broadcasts and distributes multiple wavelengths in the optical signal transmitted along the target path based on the second key to generate a multi-channel frequency hopping sequence. The wavelength of each frequency hopping sequence changes over time, and the change pattern of the frequency hopping sequence is controlled by the key group. The receiver (300) is used to receive the transmitted signal, decode the transmitted signal based on the same key group as the transmitter, and recover the original data stream sequence after conversion by multiple photodetectors (3401).

2. The optical frequency hopping communication system according to claim 1, characterized in that, The sending end includes: A first optical switch (120) is used to determine a target first path based on a first key; wherein, the first optical switch includes a plurality of first paths, and each first path corresponds to a first output port; The first broadcast routing wavelength selection switch array (130) is used to broadcast and distribute multiple wavelengths in the optical signal based on the second key to generate a multi-channel frequency hopping sequence; wherein, the frequency hopping sequence on the second path generated by the broadcast distribution depends on the output results of the second key and the first target path, that is, the signal wavelength in each second path will change over time, and the change law of the frequency hopping sequence signal is controlled by the key group.

3. The optical frequency hopping communication system according to claim 2, characterized in that, The first broadcast routing wavelength selection switch array (130) includes multiple second input ports and multiple second output ports. The second input ports are connected to the first output ports of the first optical switch and are used to receive optical signals transmitted by the first optical switch. The optical signals output by different first output ports correspond to different distribution modes in the first broadcast routing wavelength selection switch array.

4. The optical frequency hopping communication system according to claim 3, characterized in that, The transmitting end also includes: A light source emitting device (110) is used to emit optical signals, wherein the light source emitting device is a multi-channel laser array chip, or a combination of a single-wavelength light source and an optical frequency comb; The data modulation module (140) consists of multiple modulators and is used to modulate multiple data stream sequences onto each frequency hopping sequence to generate multiple modulated frequency hopping sequences; wherein the data stream sequences loaded on different frequency hopping sequences are different; wherein the multiple modulators are respectively connected to multiple second output ports in the first broadcast routing wavelength selection switch array; The transmit signal forming module (150) is composed of a multi-wavelength optical multiplexer (1501) and is used to multiplex the frequency hopping sequence with the modulation signal to generate the transmit signal; An arbitrary waveform generator (160) is used to generate multiple data stream sequences and send the multiple data stream sequences to multiple modulators respectively; A first pseudo-random code generator (170) is connected to a first optical switch (120) and a first broadcast routing wavelength selection switch array (130) for obtaining a first key and a second key, and sending the first key and the second key to the first optical switch and the first broadcast routing wavelength selection switch array, respectively.

5. The optical frequency hopping communication system according to claim 1, characterized in that, The receiving end includes: The second optical switch (320) is used to determine the target path based on the first key, wherein the transmission signal path switching mode is different for different target paths; The second broadcast routing wavelength selection switch array (330) is used to broadcast and distribute multiple wavelengths of the received transmitted signal based on the second key to recover the frequency hopping sequence.

6. The optical frequency hopping communication system according to claim 5, characterized in that, The receiving end also includes: The signal amplifier (310) is used to receive and amplify the strength of the transmitted signal after transmission through the optical fiber to compensate for the transmission loss on the optical fiber link, and to send the amplified transmitted signal to the second optical switch. The signal restoration module (340) consists of multiple photodetectors (3401) and is used to perform photoelectric conversion on the recovered frequency hopping sequence to restore multiple sets of original data stream sequences; The second pseudo-random code generator (350) is connected to the second optical switch and the second broadcast routing wavelength selection switch array, and is used to obtain the first key and the second key, and send the first key and the second key to the second optical switch and the second broadcast routing wavelength selection switch array respectively.

7. The optical frequency hopping communication system according to claim 1, characterized in that, The transmitting end (100) and the receiving end (300) are made of discrete devices connected together, or are made based on silicon-based active chips and / or group III-V active chips.

8. The optical frequency hopping communication system according to claim 2, characterized in that, The first optical switch (120) is formed by cascading two optical switches.

9. The optical frequency hopping communication system according to claim 5, characterized in that, The second optical switch (320) is formed by cascading a one-to-two optical switch.

10. An optical frequency hopping communication method, characterized in that, include: The optical signal is modulated based on the key group to generate multiple frequency hopping sequences. Then, multiple data stream sequences are modulated onto each frequency hopping sequence. The frequency hopping sequences with modulation signals are merged into the transmission signal forming module and coupled to generate a transmission signal. The transmission signal is then sent into the optical fiber for transmission. The transmitted signal is received, decoded based on the same key group as the transmitting end, and the original data stream sequence is recovered after conversion by a photodetector; The key group includes a first key and a second key, and the optical signal contains multiple wavelengths; The process of modulating the optical signal based on the key group to generate multiple frequency hopping sequences includes: determining the target path based on the first key, broadcasting and distributing multiple wavelengths in the optical signal transmitted along the target path based on the second key to generate multiple frequency hopping sequences, wherein the wavelength of each frequency hopping sequence changes over time, and the change pattern of the frequency hopping sequence is controlled by the key group.

11. The optical frequency hopping communication method according to claim 10, characterized in that, Decoding the transmitted signal based on the same key group as the transmitter includes: The target path of the transmitted signal in the second optical switch is determined based on the first key, wherein different target paths correspond to different transmission signal path switching modes; Based on the second key, the received transmitted signal is broadcast and distributed to multiple wavelengths to recover the frequency hopping sequence; The recovered frequency hopping sequence is photoelectrically converted to restore multiple sets of original data stream sequences.

Images