Quantum key distribution system based on 5G communication

Abstract

The utility model discloses a quantum key distribution system based on 5G communication. The quantum key distribution system comprises 5G communication equipment, a cloud server and a key management module, wherein the 5G communication equipment is connected with the cloud server through a 5G channel, and the cloud server is connected with the key management module through the 5G channel; the 5G communication equipment carries a quantum chip, and the quantum chip is connected with the key management module through a quantum channel. The utility model discloses a quantum key distribution system based on 5G communication, which is characterized in that a quantum chip is carried in 5G communication equipment, and 5G communication and quantum communication are closely combined, so that the communication is more convenient and safer; moreover, through a highly integrated quantum chip technology, the system can be onboard to 5G communication equipment such as a smart phone, thereby greatly widening the application scene of quantum key distribution, and facilitating the promotion of the application of QKD in a 5G quantum network and commercial passwords.

Description

Technical Field

[0001] The utility model relates to the field of 5G communication networks and quantum communication equipment, and specifically to a quantum key distribution system based on 5G communication. Background Art

[0002] With the advent of the 5G era and the IP-based communication network, various 5G devices have been active in various industries, and technological innovation has affected every aspect of our lives. The ensuing models such as the Internet of Things, cloud platforms, and 5G smart applications, as well as new-generation commercial cryptography such as quantum cryptography, will be promoted and applied on a large scale. As the Internet becomes more closely connected to life, information and communication security becomes more important. Quantum communication is based on the basic principles of quantum mechanics and has a subversive impact on the reconstruction of security in traditional industries. It is an important tool for protecting the security of information and IP-based communications in the 5G era.

[0003] Since the birth of the quantum key distribution protocol (QKD), phased results have been achieved in theory, experiment and practical application, and it has developed from the initial purely theoretical stage to the application stage. Quantum key distribution (QKD) allows remote parties to exchange keys securely. Although it has been theoretically proven that quantum key distribution technology has unconditional security, there are still potential security risks in the communication system when it is integrated and implemented with actual devices, and various equipment defects cannot be ignored.

[0004] MDI-QKD (measurement device-independent quantum key distribution) is a highly secure quantum communication protocol that ensures that both parties in communication can safely generate and share keys by eliminating potential vulnerabilities in measurement equipment. Since its proposal, the protocol has been continuously optimized and improved in theory in terms of security and distance limitations. Experimentally, MDI-QKD experiments have been implemented in a variety of scenarios, including long-distance fiber-optic communication, free-space communication, and multi-user communication. In addition, it has been incorporated into multiple standardization organizations and has become one of the important protocols in the field of quantum communication. The MDI-QKD protocol allows photons to be transmitted in free space, where photons have lower losses than in fiber channels. It also avoids the difficulty of laying long-distance fiber channels that meet quantum communication standards due to complex ground structures, which can save costs and further improve the practicality of quantum communication systems. In 2022, China Unicom Industrial Internet (Guangdong) Co., Ltd., Beijing University of Posts and Telecommunications, Guangdong Guoteng Quantum Technology Co., Ltd., and others jointly established the Ministry of Industry and Information Technology's 5G Cryptography Trusted Application Joint Laboratory.

[0005] As various QKD solutions mature and enter the promotion period, as well as the development of on-chip integration technology, system-level packaging technology and silicon photonic integrated circuits, QKD integration has become a key research area of ​​QKD. The small size of quantum chips enables QKD to be applied to various small communication devices. Miniaturization and chipization are the prerequisites for the combination of QKD and 5G communication equipment.

[0006] Most of the existing technologies that integrate 5G networks with quantum networks store keys in the cloud, and transmit the keys to the user through classical channels after the user is authenticated. In this process, eavesdroppers can easily intercept the keys sent from the cloud through classical channels, making communication security difficult to ensure. Utility Model Content

[0007] In order to solve the problem that the existing technology of integrating 5G network with quantum network is difficult to ensure communication security, the utility model proposes a quantum key distribution system based on 5G communication.

[0008] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0009] A quantum key distribution system based on 5G communication includes a 5G communication device, a cloud server and a key management module; wherein the 5G communication device is connected to the cloud server via a 5G channel, and the cloud server is connected to the key management module via a 5G channel; the 5G communication device is equipped with a quantum chip, and the quantum chip is connected to the key management module via a quantum channel.

[0010] In the above solution, by installing quantum chips in 5G communication equipment, 5G communication and quantum communication are closely integrated to make communication more convenient and safer; and through highly integrated quantum chip technology, it can be installed on board 5G communication equipment such as smartphones, greatly broadening the use scenarios of quantum key distribution.

[0011] Preferably, the quantum chip integrates a laser light source, an MZ interferometer and an adjustable optical attenuator;

[0012] The output end of the laser light source is connected to the input end of the MZ interferometer, the output end of the MZ interferometer is connected to the input end of the adjustable optical attenuator, and the output end of the adjustable optical attenuator is connected to the key management module through a quantum channel.

[0013] Preferably, the quantum chip is also integrated with a first clock signal module; the first clock signal module is externally connected to the 5G network, and the output end of the first clock signal module is connected to the input end of the laser light source.

[0014] Preferably, the MZ interferometer comprises a first multimode interference coupler, a second multimode interference coupler and a phase modulator;

[0015] The output end of the laser light source is connected to the input end of the first multimode interference coupler, the first output end of the first multimode interference coupler is connected to the first input end of the second multimode interference coupler, the second output end of the first multimode interference coupler is connected to the second input end of the second multimode interference coupler through a phase modulator, and the output end of the second multimode interference coupler is connected to the input end of the adjustable optical attenuator.

[0016] Preferably, the MZ interferometer further includes a quantum random number generator; the output end of the quantum random number generator is connected to the input end of the phase modulator.

[0017] Preferably, the first output end of the first multimode interference coupler is connected to the first input end of the second multimode interference coupler via a delay line.

[0018] Preferably, the key management module includes a quantum gateway, a key management terminal and a detection terminal;

[0019] The cloud server is connected to the key management terminal through a quantum gateway; the output end of the quantum chip is connected to the input end of the detection end through a quantum channel, and the output end of the detection end is connected to the input end of the key management terminal.

[0020] Preferably, the detection end comprises a beam splitter, a first single-photon detector and a second single-photon detector;

[0021] The output end of the quantum chip is connected to the input end of the beam splitter through a quantum channel, and the output end of the beam splitter is connected to the input end of the first single-photon detector and the input end of the second single-photon detector respectively.

[0022] Preferably, the detection end further includes a time acquisition device and a second clock signal module;

[0023] The output end of the first single-photon detector, the output end of the second single-photon detector, and the output end of the second clock signal module are respectively connected to the input end of the time acquisition device, and the output end of the time acquisition device is connected to the input end of the key management terminal.

[0024] Preferably, the first single-photon detector and the second single-photon detector are both avalanche single-photon detectors.

[0025] Beneficial technical effects of the utility model:

[0026] The utility model provides a quantum key distribution system based on 5G communication. By installing quantum chips in 5G communication equipment, 5G communication and quantum communication are closely integrated to make communication more convenient and safer. Moreover, through highly integrated quantum chip technology, it can be mounted on 5G communication equipment such as smartphones, greatly broadening the use scenarios of quantum key distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall framework of the utility model;

[0028] Figure 2 This is a schematic diagram of the module connection of the quantum chip in the utility model;

[0029] Figure 3 This is a schematic diagram of module connection at the detection end of the utility model. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the utility model more clearly understood, the utility model is further described in detail below in conjunction with embodiments, but the scope of protection claimed in the utility model is not limited to the following specific embodiments.

[0031] Example 1

[0032] like Figure 1 As shown, a quantum key distribution system based on 5G communication includes a 5G communication device, a cloud server and a key management module; wherein the 5G communication device is connected to the cloud server through a 5G channel, and the cloud server is connected to the key management module through a 5G channel; the 5G communication device is equipped with a quantum chip, and the quantum chip is connected to the key management module through a quantum channel.

[0033] In the specific implementation process, the 5G communication device as the communication party requests communication from the cloud server through the 5G channel, and the cloud server transmits the request to the key management module. After receiving the request, the key management module feeds back the result to the cloud server, and the cloud server responds quickly and sends the result to the 5G communication device; after the existing positioning judgment algorithm of the two communicating parties calculates the communication distance, they control the quantum chips on their own to emit optical signals, which are transmitted to the key management module through the quantum channel for detection, and the detection results are sent by the key management module to the two communicating parties through the cloud server. Among them, the cloud server conveniently addresses the 5G communication equipment for communication through the existing 5G network, and after 5G networking, convenient tools such as Beidou satellite positioning and networked standard clock can be used, which greatly reduces the cost of quantum communication on mobile devices.

[0034] More specifically, Figure 2As shown, the quantum chip integrates a laser light source laser, an MZ interferometer and a variable optical attenuator VOA;

[0035] The output end of the laser light source laser is connected to the input end of the MZ interferometer, the output end of the MZ interferometer is connected to the input end of the variable optical attenuator VOA, and the output end of the variable optical attenuator VOA is connected to the key management module through a quantum channel.

[0036] In the specific implementation process, the laser light emitted by the laser light source laser passes through the MZ interferometer to form two light signals with a time interval corresponding to the arm length difference of the MZ interferometer. The two light signals are attenuated into weak light signals through the variable optical attenuator VOA respectively.

[0037] More specifically, the quantum chip also integrates a first clock signal module CLOCK1; the first clock signal module CLOCK1 is externally connected to a 5G network, and the output end of the first clock signal module CLOCK1 is connected to the input end of a laser light source laser.

[0038] In the specific implementation process, the laser light source laser is driven by the first clock signal module CLOCK1 to emit laser, and the networked standard clock of the first clock signal module CLOCK1 ensures that the optical signals emitted by both communicating parties arrive at the key management module at the same time for perfect interference. The optical signal is attenuated into a weak optical signal at the single photon level by the variable optical attenuator VOA to ensure the security of communication.

[0039] More specifically, the MZ interferometer includes a first multimode interference coupler MMI1, a second multimode interference coupler MMI2 and a phase modulator PM;

[0040] The output end of the laser light source laser is connected to the input end of the first multimode interference coupler MMI1, the first output end of the first multimode interference coupler MMI1 is connected to the first input end of the second multimode interference coupler MMI2, the second output end of the first multimode interference coupler MMI1 is connected to the second input end of the second multimode interference coupler MMI2 through the phase modulator PM, and the output end of the second multimode interference coupler MMI2 is connected to the input end of the adjustable optical attenuator VOA.

[0041] More specifically, the MZ interferometer further includes a quantum random number generator QRNG; the output end of the quantum random number generator QRNG is connected to the input end of the phase modulator PM.

[0042] In the specific implementation process, the first multimode interference coupler MMI1 divides the laser light emitted by the laser light source laser into two light signals with equal light intensity, namely, the reflected light signal and the transmitted light signal; wherein, the reflected light signal is transmitted to the second multimode interference coupler MMI2 through the long arm of the MZ interferometer; the transmitted light signal is transmitted in the short arm of the MZ interferometer, and is phase-encoded by the phase modulator PM controlled by the quantum random number generator QRNG before entering the second multimode interference coupler MMI2. The reflected light signal is transmitted to the second multimode interference coupler MMI2 through the long arm of the MZ interferometer and then emitted as a reference light, and the transmitted light signal is transmitted to the second multimode interference coupler MMI2 through the short arm of the MZ interferometer and then emitted as a signal light. Among them, the multimode interference coupler plays the role of a 50:50 beam splitter BS, which separates the optical signal with equal power intensity, and has the characteristics of compact structure, low insertion loss, wide bandwidth, simple manufacturing process, good tolerance, and insensitivity to polarization. It can be customized according to needs and is easy to integrate in the chip.

[0043] More specifically, the first output end of the first multimode interference coupler MMI1 is connected to the first input end of the second multimode interference coupler MMI2 via a delay line.

[0044] In a specific implementation process, the first output end of the first multimode interference coupler MMI1 and the first input end of the second multimode interference coupler MMI2 are connected through a delay line to form a long arm of the MZ interferometer.

[0045] More specifically, the key management module includes a quantum gateway, a key management terminal and a detection terminal;

[0046] The cloud server is connected to the key management terminal through a quantum gateway; the output end of the quantum chip is connected to the input end of the detection end through a quantum channel, and the output end of the detection end is connected to the input end of the key management terminal.

[0047] More specifically, Figure 3 As shown, the detection end includes a beam splitter BS, a first single-photon detector APD1 and a second single-photon detector APD2;

[0048] The output end of the quantum chip is connected to the input end of the beam splitter BS through a quantum channel, and the output end of the beam splitter BS is connected to the input end of the first single photon detector APD1 and the input end of the second single photon detector APD2 respectively.

[0049] More specifically, the detection end further includes a time acquisition device TDC and a second clock signal module CLOCK2;

[0050] The output end of the first single photon detector APD1, the output end of the second single photon detector APD2, and the output end of the second clock signal module CLOCK2 are respectively connected to the input end of the time acquisition device TDC, and the output end of the time acquisition device TDC is connected to the input end of the key management terminal.

[0051] More specifically, the first single photon detector APD1 and the second single photon detector APD2 are both avalanche single photon detectors.

[0052] During the specific implementation process, after the optical signal enters the detection end through the quantum channel, it enters the first single-photon detector APD1 and the second single-photon detector APD2 through the beam splitter BS for measurement. The optical signal is converted into an electrical signal, and the measurement result is transmitted to the time acquisition device TDC controlled by the second clock signal module CLOCK2 for collection and recorded in the key management terminal. The key management terminal sends it to the cloud server through the quantum gateway, and the cloud server sends the result to both communicating parties.

[0053] During the specific implementation process, the cloud server transmits the communication request of the 5G communication device to the quantum gateway. After receiving the request, the quantum gateway feeds back the result to the cloud server, and the cloud server responds quickly and sends the result to the 5G communication device.

[0054] In the specific implementation process, it is assumed that the two communicating parties are Alice and Bob; after the optical signal passes through the MZ interferometer, it becomes a front and back optical signal with a time interval corresponding to the difference in arm length of the MZ interferometer, corresponding to time 0 and time 1, that is, two time-bins, which correspond to the Z basis. Among them, the time 0 optical signal passes through the short arm of the MZ interferometer, and the phase modulator PM controlled by the quantum random number generator QRNG modulates the phase difference between the time 0 optical signals of the two communicating parties to 0 or phase ±π, which correspond to the X basis, and the time 1 optical signal passes through the long arm of the MZ interferometer.

[0055] The two modes output by the MZ interferometer are called reference mode and signal mode, i.e., reference light and signal light. The reference mode represents the time 1 pulse passing through the long arm of the MZ interferometer, while the signal mode represents the time 0 pulse passing through the short arm of the phase modulator PMPM. The two are respectively used at Alice's end by a r and a s Indicates that Bob uses b r and b s Indicates that the phase modulation angles of Alice and Bob are set to: θ a ,θ b∈{0,π}. Assume that the first output of the first single-photon detector APD1APD1 and the second single-photon detector APD2APD2 are D0 and D1 respectively, and the second output is D′ respectively. 0 , D′ 1 , when D 0 and D 1 and D′ 0 and D′ 1 All other detection events, such as: D 0 and D 1 In the case where both respond, both are discarded. With the successful Bell state detection result as the condition, the successful output of Alice and Bob is expressed as follows:

[0056]

[0057] It can be expressed as:

[0058]

[0059] The detector output corresponding to the input is:

[0060]

[0061] Successful output event: D 0 or D 1 Response, D′ 0 or D′ 1 Response, corresponding output:

[0062]

[0063] When θ a -θ b =0, the successful output result is expressed as When θ a -θ b = ±π, the successful output result is expressed as When θ a -θ b = 0, the detector response caused by the interference of the signal light and the reference light is the same, and it is impossible to distinguish whether it is the correct response or the response caused by the after-pulse effect of the single-photon detector. Therefore, only θ a -θ b = ±π, discard θ a -θ b =0 when the key information is obtained.

[0064] When the first single photon detector APD1 and the second single photon detector APD2 respond twice within the time window, corresponding to two pulses one after the other, it is considered a successful coincidence measurement and the measurement result is announced. The final coding result is shown in the following table:

[0065]

[0066] The detection end sends the measurement result to the key management terminal, and the key management terminal transmits the result to the communicating parties through the 5G channel of the cloud platform. The communicating parties compare information, perform base sieving code and bit flipping according to the detection result to form a screening key; then randomly select some data from the screening key, obtain the bit error rate by calculating the screened data, and judge whether there is eavesdropping. If the bit error rate is higher than the threshold, there is eavesdropping, and the communication is terminated immediately and the generated screening code is discarded. If there is no eavesdropping, the screening key is coordinated again. The mutual information of the communicating parties remains unchanged before and after the information coordination. Finally, the data confidentiality is enhanced through the confidentiality enhancement protocol, so that the communicating parties obtain consistent quantum keys.

[0067] According to the disclosure and teaching of the above specification, the technicians in the field of the utility model can also change and modify the above implementation. Therefore, the utility model is not limited to the specific implementation methods disclosed and described above, and some modifications and changes to the utility model should also fall within the scope of protection of the claims of the utility model. In addition, although some specific terms are used in this specification, these terms are only for convenience and do not constitute any limitation to the utility model.

Claims

1. A quantum key distribution system based on 5G communication, characterized in that: It includes a 5G communication device, a cloud server and a key management module; wherein the 5G communication device is connected to the cloud server via a 5G channel, and the cloud server is connected to the key management module via a 5G channel; the 5G communication device is equipped with a quantum chip, and the quantum chip is connected to the key management module via a quantum channel; The quantum chip integrates a laser light source, an MZ interferometer and an adjustable optical attenuator; The output end of the laser light source is connected to the input end of the MZ interferometer, the output end of the MZ interferometer is connected to the input end of the adjustable optical attenuator, and the output end of the adjustable optical attenuator is connected to the key management module through a quantum channel; The key management module includes a quantum gateway, a key management terminal and a detection terminal; The cloud server is connected to the key management terminal through a quantum gateway; the output end of the quantum chip is connected to the input end of the detection end through a quantum channel, and the output end of the detection end is connected to the input end of the key management terminal; The detection end includes a beam splitter, a first single-photon detector and a second single-photon detector; The output end of the quantum chip is connected to the input end of the beam splitter through a quantum channel, and the output end of the beam splitter is connected to the input end of the first single-photon detector and the input end of the second single-photon detector respectively.

2. A quantum key distribution system based on 5G communication according to claim 1, characterized in that: The quantum chip also integrates a first clock signal module; the first clock signal module is externally connected to the 5G network, and the output end of the first clock signal module is connected to the input end of the laser light source.

3. According to a 5G communication-based quantum key distribution system according to claim 1, it is characterized in that: The MZ interferometer includes a first multimode interference coupler, a second multimode interference coupler and a phase modulator; The output end of the laser light source is connected to the input end of the first multimode interference coupler, the first output end of the first multimode interference coupler is connected to the first input end of the second multimode interference coupler, the second output end of the first multimode interference coupler is connected to the second input end of the second multimode interference coupler through a phase modulator, and the output end of the second multimode interference coupler is connected to the input end of the adjustable optical attenuator.

4. A quantum key distribution system based on 5G communication according to claim 3, characterized in that: The MZ interferometer also includes a quantum random number generator; the output end of the quantum random number generator is connected to the input end of the phase modulator.

5. A quantum key distribution system based on 5G communication according to claim 3, characterized in that: The first output end of the first multimode interference coupler is connected to the first input end of the second multimode interference coupler through a delay line.

6. A quantum key distribution system based on 5G communication according to claim 1, characterized in that: The detection end also includes a time acquisition device and a second clock signal module; The output end of the first single-photon detector, the output end of the second single-photon detector, and the output end of the second clock signal module are respectively connected to the input end of the time acquisition device, and the output end of the time acquisition device is connected to the input end of the key management terminal.

7. A quantum key distribution system based on 5G communication according to claim 1, characterized in that: The first single-photon detector and the second single-photon detector are both avalanche single-photon detectors.

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