CN110661614B - Polarization feedback device for quantum key distribution system - Google Patents
Polarization feedback device for quantum key distribution system Download PDFInfo
- Publication number
- CN110661614B CN110661614B CN201810686139.4A CN201810686139A CN110661614B CN 110661614 B CN110661614 B CN 110661614B CN 201810686139 A CN201810686139 A CN 201810686139A CN 110661614 B CN110661614 B CN 110661614B
- Authority
- CN
- China
- Prior art keywords
- qkd
- polarization
- feedback
- qkd device
- epc
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
- H04L9/0852—Quantum cryptography
- H04L9/0858—Details about key distillation or coding, e.g. reconciliation, error correction, privacy amplification, polarisation coding or phase coding
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Theoretical Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optical Communication System (AREA)
Abstract
A polarization feedback device for a quantum key distribution system uses a duplex QKD system, each of two matched QKD devices comprises a transmitting end and a receiving end, signal light and polarization reference light generated by the transmitting ends of the two QKD devices are respectively output to the receiving end of the other matched QKD device, the polarization reference light and the quantum signal light are transmitted in a time-sharing manner, an optical circulator and an EPC are arranged at the intersection position of two QKD links of each device, the EPCs of the two QKD devices are respectively connected with two ends of an optical fiber channel through single-mode optical fibers, and the receiving ends of the two QKD devices are respectively connected to the corresponding EPCs through feedback control loops. Compared with the prior art, the invention has the following advantages: two relatively independent working links of the duplex QKD system are utilized for common-fiber transmission, no extra wavelength channel is occupied, and the overall cost of the quantum key distribution system is reduced; the two links simultaneously and respectively carry out polarization feedback on one of the two groups of non-orthogonal basis vectors, so that the time for polarization feedback is saved.
Description
Technical Field
The invention relates to the field of quantum secret communication, in particular to a polarization feedback device for a quantum key distribution system.
Background
In the polarization-encoded quantum cryptography distribution scheme, since an optical fiber between a transmitting side and a receiving side may be disturbed by environmental factors and the like, the polarization of an optical signal may change, which may result in an increase in error rate of the receiving side. Polarization feedback is required in polarization encoded quantum key distribution systems in order to keep the error rate low.
In the quantum cipher distribution system, H, V light emitted by a sender should be detected under HV basis vector to respectively obtain H, V results, and when the sender and a receiver are not attacked, if V light appears in the H light detection result, it is stated that the base vector direction of the receiver and the base vector direction of the sender have partial deviation, and the deviation can be determined by the proportion of the V light to the emitted H light at this time. Accordingly, the + light, -light detection from the sender at the + -basis vector should yield + and-results, respectively. Therefore, correction is needed when the base vector of the receiving side deviates from that of the transmitting side, so as to reduce or eliminate the problem caused by the interference of the channel fiber.
As shown in fig. 1, a quantum key distribution system using an existing polarization feedback device includes a transmitting device and a receiving device connected by a quantum channel. The transmitting device comprises a QKD transmitting end Alice, a transmitting side polarized reference light preparation module and a transmitting side wavelength division multiplexing module, wherein the QKD transmitting end Alice and the transmitting side polarized reference light preparation module are connected to the transmitting side wavelength division multiplexing module; the receiving device comprises an electric polarization controller, a receiving party wavelength division multiplexing module, a receiving party polarization detection module, a feedback control device and a QKD receiving end Bob, wherein the output end of the electric polarization controller is connected to the receiving party wavelength division multiplexing module, the output end of the receiving party wavelength division multiplexing module is simultaneously connected to the receiving party polarization detection module and the QKD receiving end Bob, and the output end of the receiving party polarization detection module is connected to the electric polarization controller through the feedback control device;
the wavelength division multiplexing module of the sender is connected with the electric polarization controller through a quantum channel;
the QKD transmitting end Alice is used for transmitting quantum signal light, the transmitting side polarized reference light preparation module is used for preparing two non-orthogonal linearly polarized reference lights with fixed time delay and an included angle of 45 degrees, the transmitting side wavelength division multiplexing module is used for coupling the QKD signal light and the reference light into the same optical fiber for transmission, and the quantum channel signal light and the linearly polarized reference light are ensured to be transmitted in different time sequences by utilizing a time division multiplexing technology;
the QKD receiving end Bob is used for receiving the quantum signal light, the receiving end polarization detection module is used for receiving and feedback compensating two non-orthogonal linear polarization reference lights, and the receiving end recovers the polarization state of the signal light by counting and detecting the polarization state of the reference light and adjusting the receiving end electric polarization controller in real time by taking the polarization state as a feedback basis.
In the conventional polarization feedback method, as described above, in the QKD system, an additional polarization reference light preparation module is added, the polarization reference light and the quantum signal light are transmitted in a shared fiber in a wavelength division multiplexing manner, the polarization reference light and the quantum signal light are subjected to wavelength division multiplexing at a receiving end, then the polarization reference light is detected by using an additional polarization detection module (including a PIN detector), and the polarization reference light is subjected to feedback control based on a detection result. Because an additional polarized reference light preparation module and a polarization detection module are needed, the system cost is high, and the popularization and the application of the QKD technology are not facilitated. Moreover, the polarized reference light is strong light, and interference is generated on the quantum signal light due to the fact that the polarized reference light and the quantum signal light with weak light intensity are transmitted in a shared fiber mode, and the QKD encoding rate is remarkably reduced.
Disclosure of Invention
The invention aims to solve the technical problem that the existing polarization feedback needs an additional polarized reference light preparation module and a polarized detection module, so that the system cost is higher.
The invention solves the technical problems through the following technical scheme: a polarization feedback device for a quantum key distribution system uses a duplex QKD system, two matched QKD devices comprise a sending end Alice and a receiving end Bob, wherein, a signal light and a polarization reference light generated by the sending end of the first QKD device are output to the receiving end of the second QKD device, a signal light and a polarization reference light generated by the sending end of the second QKD device are output to the receiving end of the first QKD device, the polarization reference light and the quantum signal light are sent in a time division way, the sending end of the first QKD device and the receiving end of the second QKD device are matched into a first QKD link, the sending end of the second QKD device and the receiving end of the first QKD device are paired to form a second QKD link, an optical circulator is arranged at the intersection position of the first QKD link and the second QKD link of each device, the optical circulator of the first QKD device is connected with the first EPC through a single-mode optical fiber, the optical circulator of the second QKD device is connected with the second EPC through a single-mode optical fiber, the first EPC is connected with one end of an optical fiber channel through a single-mode optical fiber, the second EPC is connected with the other end of the optical fiber channel through a single-mode optical fiber, and the receiving ends of the first QKD device and the second QKD device are respectively connected to the corresponding first EPC and the second EPC through feedback control loops.
As a further technical solution, the two QKD devices that are paired have the same structure.
Specifically, the QKD device includes an EPC, an optical circulator, a receiving end, a transmitting end, a feedback control loop, and a single-mode fiber, where a first end of the EPC is connected to one end of an optical fiber channel through the single-mode fiber, a second end of the EPC is connected to a first port of the optical circulator through the single-mode fiber, a second port of the optical circulator is connected to the receiving end through the single-mode fiber, a third port of the optical circulator is connected to the transmitting end through the single-mode fiber, and the receiving end is connected to a third end of the EPC through the feedback control loop.
As an optimized technical scheme, the EPC adopts a six-axis electric polarization controller.
Alternatively, the EPC employs a four-axis electric polarization controller.
Alternatively, the EPC employs a three-axis electric polarization controller.
As a further technical scheme, the receiving end is configured to receive the polarized reference light and the quantum signal light, and includes a polarization maintaining beam splitter BS, a first polarization maintaining polarization beam splitter PBS1, a second polarization maintaining polarization beam splitter PBS2, a first detector D1, a second detector D2, a third detector D3, and a fourth detector D4, where the polarized reference light sent by the sending end of another QKD device in pair is split by the polarization maintaining beam splitter BS, the first polarization maintaining polarization beam splitter PBS1, and the second polarization maintaining polarization beam splitter PBS2, and is finally detected by the first detector D1, the second detector D2, the third detector D3, and the fourth detector D4.
As a further technical solution, the transmitting end includes a distributed feedback laser and a variable optical attenuator, an output end of the distributed feedback laser is connected to an input end of the variable optical attenuator, and an output end of the variable optical attenuator is connected to a third port of the optical circulator through a single mode fiber.
As an optimized technical scheme, the feedback control loop is a DSP.
Or the feedback control loop is an MCU or an ARM.
Compared with the prior art, the invention has the following advantages:
1. two relatively independent working links of the duplex QKD system are used for transmission in a common fiber, an extra wavelength channel is not required to be occupied, the overall cost of the quantum key distribution system is reduced in practical application, and the popularization and application of the QKD technology are facilitated.
2. By relying on a transmitting end and a receiving end in a matched QKD device in an original duplex QKD system, two links simultaneously and respectively carry out polarization feedback on one of two groups of non-orthogonal basis vectors, and the two groups of non-orthogonal basis vectors do not need to be respectively carried out polarization feedback, so that the time for polarization feedback is saved.
Drawings
FIG. 1 is a schematic diagram of a quantum key distribution system using a prior art polarization feedback device;
FIG. 2 is a schematic diagram of a duplex QKD system architecture;
fig. 3 is a block diagram of a QKD apparatus according to a first embodiment of the present invention;
FIG. 4 is a block diagram of a six-axis electric polarization controller;
fig. 5 is a schematic diagram reflecting the structure of the receiving end and the EPC connection relationship in fig. 3;
fig. 6 is a diagram of a transmitting end structure in fig. 3;
figure 7 is a diagram of a single photon detector operating mode.
Detailed Description
The following examples are given for the detailed implementation and specific operation of the present invention, but the scope of the present invention is not limited to the following examples.
The duplex system used in the present invention will be explained below.
A duplex Quantum Key Distribution (QKD) system includes 2 paired QKD devices, each QKD device includes a sending end Alice and a receiving end Bob, and the design of each QKD device is identical, that is, two devices paired for operation are identical, and a pair of devices can operate two QKD links at the same time, as shown in fig. 2.
In the art, there is a definition of a "two-way QKD system," which refers to a QKD implementation in which signal light is sent from a first QKD terminal to a second QKD terminal, and then back along the original optical path. Generally, the signal light transmitted from the first QKD terminal to the second QKD terminal is strong, averaging hundreds or thousands of photons per pulse, and attenuated to single photon magnitude (averaging one photon per pulse or less) at the second QKD terminal before returning to the first QKD terminal. The optical fiber link of the system has only one QKD link, and is a two-way (two-way) simplex process.
The "duplex QKD system" in the present invention is different from the "two-way QKD system" described above. According to the above definition, the "two-way QKD system" is "two-way", simplex ", and the" duplex QKD system "is" one-way ", duplex", and is a system capable of "full-duplex", each end of the duplex system includes Alice and Bob, and two QKD links can be established simultaneously. The transmitting end of the first QKD device and the receiving end of the second QKD device are paired into QKD link 1, and the transmitting end of the second QKD device and the receiving end of the first QKD device are paired into QKD link 2.
The invention provides a polarization feedback device for a quantum key distribution system, wherein each matched QKD device comprises a sending end Alice and a receiving end Bob. The signal light and the polarized reference light generated by the transmitting end of the first QKD device are output to the receiving end of the second QKD device, and the signal light and the polarized reference light generated by the transmitting end of the second QKD device are output to the receiving end of the first QKD device. The transmitting end of the first QKD device and the receiving end of the second QKD device are paired into QKD link 1, and the transmitting end of the second QKD device and the receiving end of the first QKD device are paired into QKD link 2. An optical circulator is arranged at the intersection position of the QKD link 1 and the QKD link 2 of each device, the optical circulator of the first QKD device is connected with a first EPC (electronic control polarization controller) through a single-mode optical fiber, the optical circulator of the second QKD device is connected with a second EPC (electronic control polarization controller) through a single-mode optical fiber, the first EPC is connected with one end of an optical fiber channel through a single-mode optical fiber, and the second EPC is connected with the other end of the optical fiber channel through a single-mode optical fiber. The optical circulator can control the output of optical signal from one port with very small loss as required.
The configuration of each QKD device is the same, and one of the QKD devices will be described below, and the following configuration of the QKD device is applicable to the first QKD device and the second QKD device.
As shown in fig. 3, the QKD device includes EPC (electrically controlled polarization controller) 301, optical circulator 302, receiving end 303, transmitting end 304, feedback control loop 309, single-mode optical fibers 305, 306, 307, 308.
A first end of the EPC301 is connected to one end of a fiber channel through a single-mode fiber 305, a second end of the EPC301 is connected to a first port of an optical circulator 302 through a single-mode fiber 306, a second port of the optical circulator 302 is connected to a receiving end 303 through a single-mode fiber 307, a third port of the optical circulator 302 is connected to a transmitting end 304 through a single-mode fiber 308, and the receiving end 303 is connected to a third port of the EPC through a feedback control loop 309.
Polarization feedback realizes polarization control through the EPC301, and when the bias voltage of the EPC301 is changed, the incident polarization state rotates around the EPC axis; therefore, adjusting the EPC enables control of the polarization.
In this embodiment, the EPC301 employs a six-axis electric polarization controller having six piezoelectric compression modules, as shown in fig. 4, which sequentially apply 0-degree and 45-degree directional pressures to the optical fiber. The six-axis electric polarization controller not only shows more comprehensive and more uniform polarization adjustment capability on the nation and the sphere, but also solves the problem of repeated resetting in the three-axis polarization adjustment process through a plurality of extrusion axes, and the feedback efficiency of the reference light is accelerated. Certainly, the purpose of the invention can be achieved by using a three-axis electric polarization controller or a four-axis electric polarization controller, and only through experimental verification, the polarization adjusting capability achieved by using a six-axis electric polarization controller is more comprehensive and uniform, and the feedback efficiency is higher.
The optical circulator 302 ensures that QKD link 1 and QKD link 2 are running simultaneously.
As shown in fig. 5, the receiving end 303 is configured to receive the polarized reference light and the quantum signal light, and includes a polarization maintaining beam splitter BS, polarization maintaining polarization beam splitters PBS1 and PBS2, and a first detector D1, a second detector D2, a third detector D3, and a fourth detector D4. Polarized reference light sent by a sending end of another matched QKD device is split by the polarization-preserving beam splitter BS, the polarization-preserving polarization beam splitter PBS1 and the polarization beam splitter PBS2 and is finally detected by the first detector D1, the second detector D2, the third detector D3 and the fourth detector D4.
Referring also to fig. 6, the transmitting end 304 includes a distributed feedback laser 3042 and an adjustable optical attenuator 3044. The output of the distributed feedback laser 3042 is connected to the input of the variable optical attenuator 3044 and the output of the variable optical attenuator 3044 is connected to the third port of the optical circulator 302 by a single mode fiber 308. The transmitting end 304 is configured to transmit polarized reference light and quantum signal light, the polarized reference light and the quantum signal light are transmitted in a time-sharing manner, the polarized reference light and the quantum signal light enter the optical circulator 302 through the single-mode fiber 308, then enter the EPC of another paired QKD device through the single-mode fiber 306, the EPC301, the single-mode fiber 305 and the optical fiber channel, and then reach the receiving end of the other paired QKD device through the optical circulator of the other paired QKD device. The reference light with a certain period generated by the distributed feedback laser 3042 is automatically adjusted to a suitable level in real time by the variable optical attenuator 3044 according to the power detection value of the receiving party, and then transmitted.
The feedback control loop 309 may be a micro CPU such as a DSP, a high performance MCU, an ARM, etc.
The method for polarization feedback by adopting the polarization feedback device for the quantum key distribution system comprises the following steps:
(1) When the duplex QKD system works, quantum signal light generated by a sending end of a first QKD device sequentially passes through an optical circulator of the first QKD device, an electric control polarization controller of a second QKD device, an optical circulator of the second QKD device and a receiving end of the second QKD device, and when the signal enters a single-photon detector at the receiving end of the second QKD device, the detector starts counting; similarly, the quantum signal light generated by the sending end of the second QKD device passes through the optical circulator of the second QKD device, the electronic control polarization controller of the first QKD device, the optical circulator of the first QKD device and the receiving end of the first QKD device in sequence, and when the signal enters the single-photon detector at the receiving end of the first QKD device, the detector starts to count;
(2) When the key distribution error rate of the QKD system is greater than a preset value, the system enters a polarization feedback working stage;
(3) Adjusting the single-photon detectors corresponding to the receiving ends of the first QKD device and the second QKD device to work in a linear mode; adjusting the variable optical attenuators at the transmitting ends of the first and second QKD devices to make the distributed feedback lasers at the transmitting ends of the first and second QKD devices emit reference light in a specific polarization state at the same time, where the reference light is strong light relative to the quantum signal light, for example, the transmitting end of the first QKD device emits H light (horizontally polarized reference light), and at the same time, the transmitting end of the second QKD device emits P light (+ 45-degree polarized reference light);
(4) Calculating optical contrast by the receiving ends of the first and second QKD devices according to the counting of the corresponding single-photon detectors, and if the transmitting end of the first QKD device emits H light (horizontal polarization reference light) and the transmitting end of the second QKD device emits P light (+ 45-degree polarization reference light), receiving the H light (horizontal polarization reference light) by the receiving end of the second QKD device, calculating H/V contrast, and adjusting EPC of the second QKD device until the H/V contrast reaches a set contrast; the receiving end of the first QKD device receives the P light (+ 45-degree polarized reference light), calculates the P/N contrast, and adjusts the EPC of the first QKD device until the P/N contrast reaches the set contrast;
(5) If the H/V contrast and the P/N contrast both meet the requirements, the feedback control is finished, the single-photon detectors corresponding to the receiving ends of the first QKD device and the second QKD device are adjusted to work in an avalanche mode, and the working mode diagram of the single-photon detectors is shown in figure 7; and adjusting the variable optical attenuators of the first QKD device and the second QKD device to enable the sending ends of the first QKD device and the second QKD device to send out quantum signal light, wherein the quantum signal light is weak light of a single photon level, and the QKD operation is started.
Claims (10)
1. A polarization feedback apparatus for a quantum key distribution system, comprising: the duplex QKD system is used, the two matched QKD devices comprise a sending end Alice and a receiving end Bob, wherein signal light and polarization reference light generated by the sending end of the first QKD device are output to the receiving end of the second QKD device, the signal light and the polarization reference light generated by the sending end of the second QKD device are output to the receiving end of the first QKD device, the polarization reference light and the quantum signal light are transmitted in a time-sharing manner, the sending end of the first QKD device and the receiving end of the second QKD device are matched into a first QKD link, the sending end of the second QKD device and the receiving end of the first QKD device are matched into a second QKD link, an optical circulator is arranged at the intersection position of the first QKD link and the second QKD link of each device, the optical circulator of the first QKD device is connected with the first EPC through a single-mode optical fiber, the first EPC is connected with one end of a single-mode optical fiber channel, the second EPC is connected with the other end of the single-mode optical fiber channel, and the optical circulator is connected with the second QKD device through a single-mode optical fiber channel, and the second QKD device is connected with the receiving end of the feedback control circuit through a single-mode EPC optical fiber channel;
when a signal enters the single-photon detector at the receiving end of the first or second QKD device, the corresponding detector starts counting, and when the key distribution error rate of the QKD system is greater than a preset value, the system enters a polarization feedback working stage to adjust the single-photon detectors corresponding to the receiving ends of the first and second QKD devices to work in a linear mode; adjusting the variable optical attenuators at the transmitting ends of the first and second QKD devices to enable the transmitting ends of the first and second QKD devices to simultaneously emit reference light in a specific polarization state, wherein the reference light is strong light relative to the quantum signal light, and the transmitting end of the first QKD device emits H light and the transmitting end of the second QKD device emits P light, or the transmitting end of the first QKD device emits P light and the transmitting end of the second QKD device emits H light; the receiving ends of the first QKD device and the second QKD device calculate the optical H/V contrast or P/N contrast according to the counting of the corresponding single-photon detectors, and adjust the EPCs of the corresponding ends until the optical contrast reaches the set contrast; and if the optical contrast meets the requirement, the feedback control is finished, the single-photon detectors corresponding to the receiving ends of the first QKD device and the second QKD device are adjusted to work in an avalanche mode, the adjustable optical attenuators of the first QKD device and the second QKD device are adjusted, so that the transmitting ends of the first QKD device and the second QKD device emit quantum signal light, the quantum signal light is weak light of a single-photon magnitude, and the QKD starts to work.
2. A polarization feedback device for a quantum key distribution system according to claim 1, wherein the two QKD devices paired have the same structure.
3. The polarization feedback device for the quantum key distribution system according to claim 2, wherein the QKD device comprises an EPC, an optical circulator, a receiving end, a transmitting end, a feedback control loop, and a single-mode fiber, a first end of the EPC is connected to one end of the optical fiber channel through the single-mode fiber, a second end of the EPC is connected to a first port of the optical circulator through the single-mode fiber, a second port of the optical circulator is connected to the receiving end through the single-mode fiber, a third port of the optical circulator is connected to the transmitting end through the single-mode fiber, and the receiving end is connected to a third port of the EPC through the feedback control loop.
4. The polarization feedback apparatus for a quantum key distribution system of claim 3, wherein the EPC employs a six-axis electric polarization controller.
5. The polarization feedback apparatus for a quantum key distribution system according to claim 3, wherein the EPC employs a four-axis electric polarization controller.
6. The polarization feedback apparatus for a quantum key distribution system of claim 3, wherein the EPC employs a three-axis electric polarization controller.
7. The polarization feedback device for the quantum key distribution system according to claim 3, wherein the receiving end is configured to receive the polarized reference light and the quantum signal light, and includes a polarization maintaining beam splitter BS, a first polarization maintaining beam splitter PBS1, a second polarization maintaining beam splitter PBS2, a first detector D1, a second detector D2, a third detector D3, and a fourth detector D4, and the polarized reference light sent from the sending end of the other paired QKD device is split by the polarization maintaining beam splitter BS, the first polarization maintaining beam splitter PBS1, the second polarization maintaining beam splitter PBS2, and finally detected by the first detector D1, the second detector D2, the third detector D3, and the fourth detector D4.
8. The polarization feedback device for the quantum key distribution system according to claim 3, wherein the transmitting end comprises a distributed feedback laser and a variable optical attenuator, an output end of the distributed feedback laser is connected to an input end of the variable optical attenuator, and an output end of the variable optical attenuator is connected to the third port of the optical circulator through a single mode fiber.
9. The polarization feedback apparatus for a quantum key distribution system of claim 3, wherein the feedback control loop is a DSP.
10. The polarization feedback device for a quantum key distribution system of claim 3, wherein the feedback control loop is an MCU or an ARM.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810686139.4A CN110661614B (en) | 2018-06-28 | 2018-06-28 | Polarization feedback device for quantum key distribution system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810686139.4A CN110661614B (en) | 2018-06-28 | 2018-06-28 | Polarization feedback device for quantum key distribution system |
Publications (2)
Publication Number | Publication Date |
---|---|
CN110661614A CN110661614A (en) | 2020-01-07 |
CN110661614B true CN110661614B (en) | 2023-01-31 |
Family
ID=69027354
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201810686139.4A Active CN110661614B (en) | 2018-06-28 | 2018-06-28 | Polarization feedback device for quantum key distribution system |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110661614B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113556172B (en) * | 2020-12-30 | 2024-04-16 | 广东国腾量子科技有限公司 | Light polarization correction system for QKD |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN205883270U (en) * | 2016-08-12 | 2017-01-11 | 上海国盾量子信息技术有限公司 | Duplex quantum key distribution system |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2540951B2 (en) * | 1989-08-09 | 1996-10-09 | 日本電気株式会社 | Collective polarization control method |
US20040016874A1 (en) * | 2001-01-25 | 2004-01-29 | Rao Hemonth G. | Automatic polarization controller for polarization multiplexed optical signals |
CN101403824A (en) * | 2008-10-30 | 2009-04-08 | 华东师范大学 | Real-time polarization control method suitable for quantum secret communication |
CN101917268B (en) * | 2010-08-19 | 2013-04-03 | 安徽量子通信技术有限公司 | Quantum cryptography distributing polarization feedback system and implementation method thereof |
CN103618597B (en) * | 2013-12-10 | 2017-02-01 | 国家电网公司 | Quantum key distribution system based on fast polarization feedback |
CN107733638B (en) * | 2016-08-12 | 2024-02-02 | 上海国盾量子信息技术有限公司 | Duplex quantum key distribution system and synchronization method |
CN206977443U (en) * | 2017-06-12 | 2018-02-06 | 科大国盾量子技术股份有限公司 | A kind of fast polarization feedback compensation device and Complex Channel quantum key distribution system |
-
2018
- 2018-06-28 CN CN201810686139.4A patent/CN110661614B/en active Active
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN205883270U (en) * | 2016-08-12 | 2017-01-11 | 上海国盾量子信息技术有限公司 | Duplex quantum key distribution system |
Also Published As
Publication number | Publication date |
---|---|
CN110661614A (en) | 2020-01-07 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN110620652B (en) | Quantum key distribution system and communication method thereof | |
CN106161011B (en) | Plug-and-play quantum key distribution system and method based on time-phase coding, sending end and receiving end | |
CN106161010B (en) | High-bit-rate point-to-point QKD system, transmitting end, receiving end and QKD method | |
CN106161009B (en) | Quantum key distribution system based on time-phase encoding | |
US9246602B2 (en) | Quantum encryption communication apparatus, quantum encryption communication method, and quantum encryption communication system | |
EP2885886B1 (en) | Quantum communications system with integrated photonic devices | |
CN109039594B (en) | Quick polarization feedback compensation device and complex channel quantum key distribution system | |
CN106716915B (en) | Information communication system, information communication method and apparatus | |
CN210112021U (en) | Polarization encoding quantum key distribution system | |
CN109039621B (en) | Method, device and corresponding system for decoding direct current modulation quantum key distribution phase | |
CN111555878A (en) | Integrated measuring equipment independent quantum key distribution system | |
CN113708931A (en) | Polarization encoding device for quantum key distribution and quantum key distribution system | |
CN110247755A (en) | A kind of attack apparatus for demonstrating and attack demenstration method | |
CN210839584U (en) | Quantum key distribution system | |
CN111565102B (en) | Quantum key distribution system based on free space | |
CN109586799B (en) | Polarization feedback method and device for polarization coding measurement equipment independent system | |
CN110661614B (en) | Polarization feedback device for quantum key distribution system | |
CN110661616B (en) | Polarization feedback method for quantum key distribution system | |
KR102175952B1 (en) | Quantum communication control device, quantum communication system having the same, and method for designing the same | |
Chandrasekaran et al. | Photon information efficient communication through atmospheric turbulence—Part II: Bounds on ergodic classical and private capacities | |
CN114465716B (en) | MRR-QKD-based trusted relay quantum key distribution system | |
CN107733638B (en) | Duplex quantum key distribution system and synchronization method | |
WO2021013989A1 (en) | Method to set a common polarization reference frame | |
CN210609186U (en) | Quantum coding device and application system | |
Kurochkin et al. | Quantum key distribution for ultra-long distances based on microsatellites |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |