CN112491547B - Atmospheric turbulence optical channel shared random bit extraction system - Google Patents
Atmospheric turbulence optical channel shared random bit extraction system Download PDFInfo
- Publication number
- CN112491547B CN112491547B CN202011393371.2A CN202011393371A CN112491547B CN 112491547 B CN112491547 B CN 112491547B CN 202011393371 A CN202011393371 A CN 202011393371A CN 112491547 B CN112491547 B CN 112491547B
- Authority
- CN
- China
- Prior art keywords
- optical
- port
- optical switch
- end transceiver
- zero
- 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
- H04L9/0861—Generation of secret information including derivation or calculation of cryptographic keys or passwords
- H04L9/0869—Generation of secret information including derivation or calculation of cryptographic keys or passwords involving random numbers or seeds
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
- H04B10/0795—Performance monitoring; Measurement of transmission parameters
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/11—Arrangements specific to free-space transmission, i.e. transmission through air or vacuum
- H04B10/112—Line-of-sight transmission over an extended range
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/501—Structural aspects
- H04B10/503—Laser transmitters
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/70—Photonic quantum communication
-
- 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
- H04L9/085—Secret sharing or secret splitting, e.g. threshold schemes
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Electromagnetism (AREA)
- Computer Security & Cryptography (AREA)
- Optics & Photonics (AREA)
- Theoretical Computer Science (AREA)
- Optical Communication System (AREA)
Abstract
The invention discloses an atmospheric turbulence optical channel shared random bit extraction system based on space diversity time-sharing gating. The invention randomly changes the space diversity sub-channel through which the laser signal emitted by the laser reaches the photoelectric detector by using time-sharing gating, thereby realizing the random switching measurement of different sub-channels of the space diversity; by carrying out random switching measurement on different sub-channels of space diversity, the received optical signal sampling operation can ensure that the received optical signal sampling values obtained by two continuous sampling measurements are approximately statistically irrelevant under the condition of using a sampling time interval smaller than the fading autocorrelation time length of the atmospheric turbulence optical signal. Thus, when the random bit extraction rate is increased by reducing the sampling time interval of the computer acquisition system, the damage to the randomness of the extracted bit sequence can be mitigated using the present invention.
Description
Technical Field
The invention belongs to the technical field of information security, and relates to an atmospheric turbulence optical channel shared random bit extraction system based on space diversity time-sharing gating.
Background
An invention patent in china with application number 201911247093.7 discloses an atmospheric turbulence optical channel shared random bit extraction method based on a spectrum domain. The background section of the specification of this patent mentions that, in general, in order to ensure that the extracted bit sequence has good randomness, the time interval between two consecutive sampling measurements is required to be greater than the autocorrelation time length of random optical signal fading. The invention patent of china with application number 201911247093.7 firstly transforms the continuous collected random optical signal fading time domain data to the frequency spectrum domain, and then performs thresholding processing to each frequency spectrum component to extract random bits; the method can improve the randomness of the extracted bit sequence. However, the statistical mean of the magnitudes of the transformed spectral components decreases significantly with increasing frequency. On the other hand, the statistical mean of the magnitudes of the spectral components of the detector output noise generally decreases relatively slowly with increasing frequency. This results in a low snr of the transformed high frequency components, resulting in an increased rate of inconsistency of the extracted bit sequences at both ends of the channel. The "BER Performance of Free-Space Optical Transmission with Spatial Diversity" paper published in IEEE Transactions on Wireless Communications, volume 6, 2007, volume 8, discusses the effect of using a Spatial Diversity (Spatial Diversity) approach to suppress the effect of atmospheric turbulence on Free-Space Optical communication error rate Performance. The correlation between different subchannels in a spatial diversity is typically low. In practice, if the spacing between the various transceivers is large enough, the correlation between the sub-channels is typically negligible.
When measuring the received optical signal of a single sub-channel, if the sampling time interval is not large enough, there may be a strong correlation between two consecutive sampled values measured. However, if the measurement is switched between different sub-channels, for example, for the case of n sub-channels, the sampling value 1 is obtained by measuring the 1 st sub-channel received optical signal at the 1 st sampling time, the sampling value 2 is obtained by measuring the 2 nd sub-channel received optical signal at the 2 nd sampling time, and so on, the sampling value n is obtained by measuring the nth sub-channel received optical signal at the nth sampling time, then the sampling value n +1 is obtained by measuring the 1 st sub-channel received optical signal at the n +1 th sampling time, and so on, the correlation between two adjacent sampling values of the obtained sampling value sequence is obviously smaller than the correlation between two adjacent sampling values of the sampling value sequence obtained by simply measuring a single sub-channel. Therefore, the received optical signal sampling value sequence obtained by performing switching measurement on different sub-channels with space diversity is more beneficial to ensure the randomness of the bit sequence extracted from the atmospheric turbulence optical channel. In other words, by performing switching measurement on different sub-channels of spatial diversity, it can be ensured that the received optical signal sampling values obtained by two consecutive sampling measurements are approximately statistically independent even if the photodetection operation is performed at sampling intervals shorter than the fading autocorrelation time length of the atmospheric turbulence optical signal. By utilizing this property, the random bit extraction rate can be increased by reducing the sampling time interval without significantly impairing the randomness of the bit sequence. The present invention refers to the operation of switching different subchannels for spatial diversity as time-shared gating. The invention discloses an atmospheric turbulence optical channel shared random bit extraction system based on space diversity time-sharing gating, which can support the switching measurement operation and extract a shared random bit sequence.
Disclosure of Invention
The invention aims to provide an atmospheric turbulence optical channel shared random bit extraction system based on space diversity time-sharing gating, so that the rate of extracting shared random bits from an optical channel disturbed by atmospheric turbulence can be improved by using a sampling time interval smaller than the fading autocorrelation time length of an atmospheric turbulence optical signal.
The invention discloses an atmospheric turbulence optical channel sharing random bit extraction system based on space diversity time-sharing gating, which comprises a first space diversity terminal machine, a second space diversity terminal machine and an atmospheric turbulence channel, wherein the first space diversity terminal machine and the second space diversity terminal machine respectively receive, detect and sample laser signals transmitted by the atmospheric turbulence channel and sent from an opposite side, and extract random bits according to obtained sampling values.
As shown in fig. 1, the first space diversity terminal and the second space diversity terminal transmit the respective transmitted optical signals to each other through an atmospheric turbulence channel. The first space diversity terminal machine is arranged at the left end of the atmosphere turbulence channel, and the second space diversity terminal machine is arranged at the right end of the atmosphere turbulence channel. The first space diversity terminal comprises a first laser (100), a first optical fiber circulator (101), a 1 xN optical switch (102), a first left-end transceiver (103), a second left-end transceiver (104), an Nth left-end transceiver (105), a first optical switch gating control module (106), a first computer acquisition system (107) and a first photoelectric detector (108). The second space diversity terminal machine comprises a second laser (200), a second optical fiber circulator (201), a 1 xM optical switch (202), a first right-end transceiver (203), a second right-end transceiver (204), an Mth right-end transceiver (205), a second optical switch gating control module (206), a second computer acquisition system (207) and a second photoelectric detector (208).
A laser output port of the first laser (100) is connected to a first port of the first optical fiber circulator (101) through a single mode fiber, a second port of the first optical fiber circulator (101) is connected to a zero-number optical port of the 1 × N optical switch (102) through a single mode fiber, a first-number optical port of the 1 × N optical switch (102) is connected to the first left-end transceiver (103) through a single mode fiber, a second-number optical port of the 1 × N optical switch (102) is connected to the second left-end transceiver (104) through a single mode fiber, and so on, an N-number optical port of the 1 × N optical switch (102) is connected to the nth left-end transceiver (105) through a single mode fiber; and a control signal output port of the first optical switch gating control module (106) is connected with a gating control port of the 1 xN optical switch (102) through a signal line. The ports of the 1 xn optical switch (102) are shown in fig. 2.
A laser output port of the second laser (200) is connected to a first port of the second optical fiber circulator (201) through a single mode fiber, a second port of the second optical fiber circulator (201) is connected to a zero-number optical port of the 1 xm optical switch (202) through a single mode fiber, a first-number optical port of the 1 xm optical switch (202) is connected to the first right-end transceiver (203) through a single mode fiber, a second-number optical port of the 1 xm optical switch (202) is connected to the second right-end transceiver (204) through a single mode fiber, and so on, a M-number optical port of the 1 xm optical switch (202) is connected to the mth right-end transceiver (205) through a single mode fiber; and a control signal output port of the second optical switch gating control module (206) is connected with a gating control port of the 1 xM optical switch (202) through a signal line. The ports of the 1 xm optical switch (202) are shown in fig. 3.
A laser signal emitted by the first laser (100) enters the first optical fiber circulator (101) from a first port of the first optical fiber circulator (101), is emitted from a second port of the first optical fiber circulator (101), then reaches the 1 xN optical switch (102), and finally enters an atmospheric turbulence channel through the left-end transceiver corresponding to an optical port communicated with a zero-number optical port of the 1 xN optical switch (102); after the laser signal transmitted from the first laser (100) reaches the second space diversity end machine through an atmospheric turbulence channel, the first right end transceiver (203), the second right end transceiver (204), and so on to the Mth right end transceiver (205) of the second space diversity end machine all receive a part of the laser signal; only the laser signal received by the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) can enter the second port of the second optical fiber circulator (201) through the 1 xm optical switch (202) and exit from the third port of the second optical fiber circulator (201); a laser signal emitted from a third port of the second optical fiber circulator (201) is incident on the second photoelectric detector (208) through a single-mode optical fiber; the electrical signal output by the second photodetector (208) is transmitted to the second computer acquisition system (207) through a signal line, and the second computer acquisition system (207) samples and quantizes the electrical signal output by the second photodetector (208) and stores the sampled value in a memory.
Laser signals emitted by the second laser (200) enter the second optical fiber circulator (201) from a first port of the second optical fiber circulator (201), exit from a second port of the second optical fiber circulator (201), then reach the 1 xM optical switch (202), and finally enter an atmospheric turbulence channel through the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xM optical switch (202); after the laser signal transmitted from the second laser (200) reaches the first space diversity terminal through an atmospheric turbulence channel, the first left-end transceiver (103), the second left-end transceiver (104), and so on until the Nth left-end transceiver (105) of the first space diversity terminal receive a part of the laser signal; only the laser signal received by the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) can enter the second port of the first optical fiber circulator (101) through the 1 xN optical switch (102) and exit from the third port of the first optical fiber circulator (101); a laser signal emitted from a third port of the first optical fiber circulator (101) is incident on the first photoelectric detector (108) through a single-mode optical fiber; the electrical signal output by the first photodetector (108) is transmitted to the first computer acquisition system (107) through a signal line, and the first computer acquisition system (107) samples and quantizes the electrical signal output by the first photodetector (108) and stores the sampled value in a memory.
The first optical switch gating control module (106) is arranged at intervals deltatChanging the output control signal to change the optical port communication mode of the 1 × N optical switch (102) once, specifically, randomly selecting one optical port in an equal probability manner among the optical ports of the other N-1 × N optical switches (102) which are not currently communicated with the zero-number optical port of the 1 × N optical switch (102), and communicating the selected optical port of the 1 × N optical switch (102) with the zero-number optical port of the 1 × N optical switch (102).
The second optical switch gating control module (206) is used for controlling the switching of the second optical switch at intervals deltatChanging an output control signal to change the optical port connection mode of the 1 × M optical switch (202) once, specifically, randomly selecting one optical port in an equal probability manner among the optical ports of M-1 other 1 × M optical switches (202) that are not currently connected to the zero-numbered optical port of the 1 × M optical switch (202), and connecting the selected optical port of the 1 × M optical switch (202) to the zero-numbered optical port of the 1 × M optical switch (202).
If the optical port communicated with the zero-sign optical port of the 1 xN optical switch (102) is the first optical port of the 1 xN optical switch (102), the left transceiver corresponding to the optical port communicated with the zero-sign optical port of the 1 xN optical switch (102) is the first left transceiver (103); if the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) is the second optical port of the 1 xN optical switch (102), the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) is the second left-end transceiver (104); by analogy, if the optical port communicated with the zero-sign optical port of the 1 × N optical switch (102) is an N-sign optical port of the 1 × N optical switch (102), the left transceiver corresponding to the optical port communicated with the zero-sign optical port of the 1 × N optical switch (102) is the nth left transceiver (105).
If the optical port communicated with the zero-sign optical port of the 1 xM optical switch (202) is the first optical port of the 1 xM optical switch (202), the right-end transceiver corresponding to the optical port communicated with the zero-sign optical port of the 1 xM optical switch (202) is the first right-end transceiver (203); if the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) is the second optical port of the 1 xm optical switch (202), the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) is the second right-end transceiver (204); by analogy, if the optical port communicated with the zero-number optical port of the 1 × M optical switch (202) is the M-number optical port of the 1 × M optical switch (202), the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 × M optical switch (202) is the mth right-end transceiver (205).
Obtaining sampled values of the received optical signal and extracting random bits requires performing operation S1, operation S2, and operation S3.
S1: at slave time tbTo time teAt time intervals delta, said first computer acquisition system (107) is arranged to acquire data at intervals deltasSampling and quantizing the electrical signal output by the first photodetector (108) once, and storing the sampled value obtained by each sampling and quantizing operation in the memory of the first computer acquisition system (107) to form a first sampled value sequence; at slave time t bTo time teAt time intervals delta, said second computer acquisition system (207) being arranged at intervals deltasThe electrical signal output by the second photodetector (208) is sampled and quantized once and the samples resulting from each sampling and quantization operation are stored in the memory of the second computer acquisition system (207) to form a second sample value sequence.
S2: the first computer acquisition system (107) extracts NUM bits from the first sampling value sequence, the second computer acquisition system (207) extracts NUM bits from the second sampling value sequence, NUM represents the number of sampling values contained in the first sampling value sequence, and the number of sampling values contained in the first sampling value sequence is equal to the number of sampling values contained in the second sampling value sequenceThe number of sample values; -calculating in said first computer acquisition system (107) an empirically accumulated distribution function F of the sample values of said first sample value sequence, taking each sample value of said first sample value sequence as a random observation value1(x) And calculate
Handle Tx1As a decision threshold for extracting a random bit sequence; for the ith sample value of the first sample value sequence, i is 1,2,3, …, NUM, if the ith sample value of the first sample value sequence is greater than T x1-the ith bit extracted by said first computer acquisition system (107) from said first sequence of sample values is 1, otherwise the ith bit extracted by said first computer acquisition system (107) from said first sequence of sample values is 0; -calculating in said second computer acquisition system (207) an empirically accumulated distribution function F of the samples of said second sequence of sample values, taking each sample of said second sequence of sample values as a random observation2(x) And calculate
Handle Tx2As a decision threshold for extracting a random bit sequence; j is 1,2,3, …, NUM for the j-th sampling value of the second sampling value sequence, if the j-th sampling value of the second sampling value sequence is greater than Tx2If the value of the jth bit extracted from the second sample value sequence by the second computer acquisition system (207) is 1, otherwise, the jth bit extracted from the second sample value sequence by the second computer acquisition system (207) is 0.
S3: and correcting inconsistent bits in the bit sequence containing NUM bits extracted by the first computer acquisition system (107) and the bit sequence containing NUM bits extracted by the second computer acquisition system (207) by utilizing error code estimation, key agreement and error check technologies in the process after quantum key distribution, so that the first computer acquisition system (107) and the second computer acquisition system (207) have the same bit sequence.
The invention has the following positive effects: the invention randomly changes the space diversity sub-channel through which the laser signal emitted by the laser reaches the photoelectric detector by using time-sharing gating, thereby realizing the random switching measurement of different sub-channels of space diversity; by carrying out random switching measurement on different sub-channels of space diversity, the received optical signal sampling operation can ensure that the received optical signal sampling values obtained by two continuous sampling measurements are approximately statistically irrelevant under the condition of using a sampling time interval smaller than the fading autocorrelation time length of the atmospheric turbulence optical signal. Thus, when the random bit extraction rate is increased by reducing the sampling time interval of the computer acquisition system, the damage to the randomness of the extracted bit sequence can be mitigated using the present invention.
Drawings
Fig. 1 is a schematic diagram of an atmospheric turbulence optical channel shared random bit extraction system based on spatial diversity time-sharing gating.
Fig. 2 is a schematic diagram of a 1 × N optical switch.
Fig. 3 is a schematic diagram of a 1 × M optical switch.
Detailed Description
In order that the features and advantages of the method may be more clearly understood, the method is further described below in connection with specific embodiments. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. In the present embodiment, the first space-diversity terminal and the second space-diversity terminal are respectively located on the roofs of two high buildings. In this embodiment, the first photodetector (108) and the second photodetector (208) are PIN photodetectors. The first laser (100) and the second laser (200) output laser signals with stable power, and the power of the laser signals output by the first laser (100) is equal to the power of the laser signals output by the second laser (200). The article published in the journal of cryptography 2015, volume 2, and pages 113 to 121, introduces error code estimation, key agreement, and error checking operations in the post-processing of quantum key distribution in detail. The error code estimation, key negotiation and error check technologies used in the quantum key distribution post-processing can be used for carrying out inconsistent bit error correction on the original shared random bit sequences extracted by the two space diversity terminal machines, and the finally obtained shared random bit sequence is determined to be changed into a shared random bit sequence which can be used in practice. The atmospheric turbulence optical channel based on space diversity time-sharing gating still belongs to a Common-transition-Spatial-Mode Coupling (CTSMC) transceiving Mode due to the use of an optical fiber circulator and a single-Mode optical fiber, so that a bidirectional channel can be ensured to be reciprocal.
The invention discloses an atmospheric turbulence optical channel sharing random bit extraction system based on space diversity time-sharing gating, which comprises a first space diversity terminal machine, a second space diversity terminal machine and an atmospheric turbulence channel, wherein the first space diversity terminal machine and the second space diversity terminal machine respectively receive, detect and sample laser signals transmitted by the atmospheric turbulence channel and sent from an opposite side, and extract random bits according to obtained sampling values.
As shown in fig. 1, the first space diversity terminal and the second space diversity terminal transmit the respective transmitted optical signals to each other through an atmospheric turbulence channel. The first space diversity terminal machine is arranged at the left end of the atmosphere turbulence channel, and the second space diversity terminal machine is arranged at the right end of the atmosphere turbulence channel. The first space diversity terminal machine comprises a first laser (100), a first optical fiber circulator (101), a 1 xN optical switch (102), a first left-end transceiver (103), a second left-end transceiver (104), an Nth left-end transceiver (105), a first optical switch gating control module (106), a first computer acquisition system (107) and a first photoelectric detector (108). The second space diversity end machine comprises a second laser (200), a second optical fiber circulator (201), a 1 xM optical switch (202), a first right-end transceiver (203), a second right-end transceiver (204), an Mth right-end transceiver (205), a second optical switch gating control module (206), a second computer acquisition system (207) and a second photoelectric detector (208).
A laser output port of the first laser (100) is connected to a first port of the first optical fiber circulator (101) through a single mode fiber, a second port of the first optical fiber circulator (101) is connected to a zero-number optical port of the 1 × N optical switch (102) through a single mode fiber, a first-number optical port of the 1 × N optical switch (102) is connected to the first left-end transceiver (103) through a single mode fiber, a second-number optical port of the 1 × N optical switch (102) is connected to the second left-end transceiver (104) through a single mode fiber, and so on, an N-number optical port of the 1 × N optical switch (102) is connected to the nth left-end transceiver (105) through a single mode fiber; and a control signal output port of the first optical switch gating control module (106) is connected with a gating control port of the 1 xN optical switch (102) through a signal line. The ports of the 1 xn optical switch (102) are shown in fig. 2.
A laser output port of the second laser (200) is connected to a first port of the second optical fiber circulator (201) through a single mode fiber, a second port of the second optical fiber circulator (201) is connected to a zero-number optical port of the 1 xm optical switch (202) through a single mode fiber, a first-number optical port of the 1 xm optical switch (202) is connected to the first right-end transceiver (203) through a single mode fiber, a second-number optical port of the 1 xm optical switch (202) is connected to the second right-end transceiver (204) through a single mode fiber, and so on, a M-number optical port of the 1 xm optical switch (202) is connected to the mth right-end transceiver (205) through a single mode fiber; and a control signal output port of the second optical switch gating control module (206) is connected with a gating control port of the 1 xM optical switch (202) through a signal line. The ports of the 1 xm optical switch (202) are shown in fig. 3.
A laser signal emitted by the first laser (100) enters the first optical fiber circulator (101) from a first port of the first optical fiber circulator (101), is emitted from a second port of the first optical fiber circulator (101), then reaches the 1 xN optical switch (102), and finally enters an atmospheric turbulence channel through the left-end transceiver corresponding to an optical port communicated with a zero-number optical port of the 1 xN optical switch (102); after the laser signal transmitted from the first laser (100) reaches the second space diversity end machine through an atmospheric turbulence channel, the first right end transceiver (203), the second right end transceiver (204), and so on to the Mth right end transceiver (205) of the second space diversity end machine all receive a part of the laser signal; only the laser signal received by the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) can enter the second port of the second optical fiber circulator (201) through the 1 xm optical switch (202) and exit from the third port of the second optical fiber circulator (201); a laser signal emitted from a third port of the second optical fiber circulator (201) is incident on the second photoelectric detector (208) through a single-mode optical fiber; the electrical signal output by the second photodetector (208) is transmitted to the second computer acquisition system (207) through a signal line, and the second computer acquisition system (207) samples and quantizes the electrical signal output by the second photodetector (208) and stores the sampled value in a memory.
Laser signals emitted by the second laser (200) enter the second optical fiber circulator (201) from a first port of the second optical fiber circulator (201), exit from a second port of the second optical fiber circulator (201), then reach the 1 xM optical switch (202), and finally enter an atmospheric turbulence channel through the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xM optical switch (202); after the laser signal transmitted from the second laser (200) reaches the first space diversity terminal through an atmospheric turbulence channel, the first left-end transceiver (103), the second left-end transceiver (104), and so on until the Nth left-end transceiver (105) of the first space diversity terminal receive a part of the laser signal; only the laser signal received by the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) can enter the second port of the first optical fiber circulator (101) through the 1 xN optical switch (102) and exit from the third port of the first optical fiber circulator (101); a laser signal emitted from a third port of the first optical fiber circulator (101) is incident on the first photoelectric detector (108) through a single-mode optical fiber; the electric signal output by the first photoelectric detector (108) is transmitted to the first computer acquisition system (107) through a signal line, and the first computer acquisition system (107) samples and quantifies the electric signal output by the first photoelectric detector (108) and stores the sampled value in a memory.
The first optical switch gating control moduleThe blocks (106) are spaced at intervals deltatChanging the output control signal to change the optical port communication mode of the 1 xN optical switch (102) once, specifically, randomly selecting one optical port in an equal probability mode from the other N-1 optical ports of the 1 xN optical switch (102) which are not currently communicated with the zero-number optical port of the 1 xN optical switch (102), and communicating the selected optical port of the 1 xN optical switch (102) with the zero-number optical port of the 1 xN optical switch (102).
The second optical switch gating control module (206) is used for controlling the switching of the second optical switch at intervals deltatChanging the output control signal to change the optical port communication mode of the 1 xM optical switch (202) once, specifically, randomly selecting one optical port in an equal probability mode from the optical ports of the other M-1 xM optical switches (202) which are not currently communicated with the zero-number optical port of the 1 xM optical switch (202), and communicating the selected optical port of the 1 xM optical switch (202) with the zero-number optical port of the 1 xM optical switch (202).
If the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) is the first optical port of the 1 xN optical switch (102), the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) is the first left-end transceiver (103); if the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) is the second optical port of the 1 xN optical switch (102), the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch (102) is the second left-end transceiver (104); by analogy, if the optical port communicated with the zero-number optical port of the 1 × N optical switch (102) is the N-number optical port of the 1 × N optical switch (102), the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 × N optical switch (102) is the nth left-end transceiver (105).
If the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) is the first optical port of the 1 xm optical switch (202), the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) is the first right-end transceiver (203); if the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) is the second optical port of the 1 xm optical switch (202), the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch (202) is the second right-end transceiver (204); by analogy, if the optical port communicated with the zero-sign optical port of the 1 × M optical switch (202) is an M-sign optical port of the 1 × M optical switch (202), the right-end transceiver corresponding to the optical port communicated with the zero-sign optical port of the 1 × M optical switch (202) is the mth right-end transceiver (205).
Obtaining sample values of the received optical signal and extracting random bits requires performing operations S1, S2, and S3.
S1: at slave time tbTo time teAt time intervals delta, said first computer acquisition system (107) is arranged to acquire data at intervals deltasSampling and quantizing the electrical signal output by the first photodetector (108) once, and storing the sampled value obtained by each sampling and quantizing operation in the memory of the first computer acquisition system (107) to form a first sampled value sequence; at slave time t bTo time teAt time intervals delta, said second computer acquisition system (207) being arranged at intervals deltasThe electrical signal output by the second photodetector (208) is sampled and quantized once and the samples resulting from each sampling and quantization operation are stored in the memory of the second computer acquisition system (207) to form a second sample value sequence.
S2: the first computer acquisition system (107) extracts NUM bits from the first sample value sequence, the second computer acquisition system (207) extracts NUM bits from the second sample value sequence, NUM represents the number of sample values contained in the first sample value sequence, and the number of sample values contained in the first sample value sequence is equal to the number of sample values contained in the second sample value sequence; calculating the second sample value in the first computer acquisition system (107) taking each sample value of the first sample value sequence as a random observed valueEmpirical cumulative distribution function F of sampling values of a sequence of sampling values1(x) And calculate
Handle Tx1As a decision threshold for extracting a random bit sequence; for the ith sample value of the first sample value sequence, i is 1,2,3, …, NUM, if the ith sample value of the first sample value sequence is greater than T x1If the ith bit extracted from the first sample value sequence by the first computer acquisition system (107) is 1, otherwise the ith bit extracted from the first sample value sequence by the first computer acquisition system (107) is 0; -calculating in the second computer acquisition system (207) an empirically accumulated distribution function F of the samples of the second sequence of sample values, taking each sample of the second sequence of sample values as a random observed value2(x) And calculate
Handle Tx2As a decision threshold for extracting a random bit sequence; j is 1,2,3, …, NUM for the j-th sampling value of the second sampling value sequence, if the j-th sampling value of the second sampling value sequence is greater than Tx2If the value of the jth bit extracted from the second sample value sequence by the second computer acquisition system (207) is 1, otherwise, the jth bit extracted from the second sample value sequence by the second computer acquisition system (207) is 0.
S3: and correcting inconsistent bits in the bit sequence containing NUM bits extracted by the first computer acquisition system (107) and the bit sequence containing NUM bits extracted by the second computer acquisition system (207) by using error code estimation, key agreement and error check technologies in quantum key distribution post-processing, so that the first computer acquisition system (107) and the second computer acquisition system (207) have the same bit sequence.
The first space diversity terminal machine comprises N left end transceivers, and the second space diversity terminal machine comprises M right end transceivers. Each left-end transceiver is connected with a corresponding optical port of the 1 × N optical switch (102) through a single-mode optical fiber, that is, a first optical port of the 1 × N optical switch (102) is connected with the first left-end transceiver (103), a second optical port of the 1 × N optical switch (102) is connected with the second left-end transceiver (104), and so on. The laser signal received by each left-end transceiver can be coupled into the optical port of the 1 xn optical switch (102) connected to the left-end transceiver through a single-mode optical fiber. Laser signals exiting the optical ports of the 1 xn optical switches (102) connected to each left-end transceiver may be transmitted through a single mode fiber to the left-end transceiver and launched into the atmospheric turbulence channel.
Each right-end transceiver is connected with a corresponding optical port of the 1 × M optical switch (202) through a single-mode fiber, that is, a first optical port of the 1 × M optical switch (202) is connected with the first right-end transceiver (203), a second optical port of the 1 × M optical switch (202) is connected with the second right-end transceiver (204), and the rest is similar. The laser signals received by each right-hand transceiver may be coupled into an optical port of the 1 xm optical switch (202) connected to the right-hand transceiver via a single mode optical fiber. Laser signals exiting the optical ports of the 1 xm optical switch (202) associated with each right-hand transceiver may be transmitted through a single mode optical fiber to the right-hand transceiver and launched into an atmospheric turbulence channel.
In the present embodiment, N is 3 and M is 3. The zero-sign optical port of the 1 xN optical switch (102) can be communicated with any other optical port of the 1 xN optical switch (102). The zero-sign optical port of the 1 xm optical switch (202) may communicate with any other optical port of the 1 xm optical switch (202).
As shown in fig. 2, the 1 × N optical switch (102) includes N optical ports in addition to the zero-sign optical port. Each of the other optical ports of the 1 xN optical switch (102), except the zero-number optical port, is connected to a left-end transceiver via a single-mode optical fiber. As shown in fig. 3, the 1 × M optical switch (202) includes M optical ports in addition to the zero-sign optical port. Each of the other optical ports of the 1 xm optical switch (202), except the zero-number optical port, is connected to a right-end transceiver via a single-mode optical fiber. Although N is 3 and M is 3 in the present embodiment, N and M may take other integer values greater than 1 in the present invention, for example, N is 4 and M is 5.
In the present embodiment, δt0.2 ms, δs0.5 ms, tb0 ms, te(iii) 5000 milliseconds, the first computer acquisition system (107) and the second computer acquisition system (207) are simultaneously from time tbThe sampling is started.
In the embodiment, when the atmospheric turbulence optical channel sharing random bit extraction system based on space diversity time sharing gating starts to work normally, the first optical switch gating control module (106) and the second optical switch gating control module (206) start to work at intervals of delta tThe communication modes of the optical ports of the 1 xN optical switch (102) and the 1 xM optical switch (202) are changed once respectively. In this embodiment, the 1 × N optical switch (102) and the 1 × M optical switch (202) are both 1 × 3 magneto-optical switches, and the switching speed thereof is less than 30 μ sec.
In this embodiment, the first computerized acquisition system (107) and the second computerized acquisition system (207) are interconnected via the internet. The internet provides a channel for transmitting data for the error code estimation, key agreement and error check technology.
It will be appreciated by those skilled in the art that the ith bit of the bit sequence including NUM bits extracted by the first computer acquisition system (107) in operation S3 is the ith bit, i ═ 1,2,3, …, NUM extracted from the first sample value sequence by the first computer acquisition system (107) in operation S2. The j-th bit of the bit sequence including NUM bits extracted by the second computer acquisition system (207) in operation S3 is the j-th bit extracted by the second computer acquisition system (207) from the second sample value sequence in operation S2, where j is 1,2,3, …, NUM.
Claims (1)
1. A space diversity time-sharing gating-based atmospheric turbulence optical channel shared random bit extraction system is characterized by comprising a first space diversity terminal machine, a second space diversity terminal machine and an atmospheric turbulence channel, wherein the first space diversity terminal machine and the second space diversity terminal machine respectively receive, detect and sample laser signals transmitted by the atmospheric turbulence channel and sent from an opposite side, and extract random bits according to obtained sampling values;
The first space diversity terminal and the second space diversity terminal transmit the optical signals transmitted by the first space diversity terminal and the second space diversity terminal to each other through an atmospheric turbulence channel; the first space diversity terminal machine is arranged at the left end of the atmosphere turbulence channel, and the second space diversity terminal machine is arranged at the right end of the atmosphere turbulence channel; the first space diversity terminal machine comprises a first laser, a first optical fiber circulator, a 1 XN optical switch, a first left-end transceiver, a second left-end transceiver, …, an Nth left-end transceiver, a first optical switch gating control module, a first computer acquisition system and a first photoelectric detector; the second space diversity terminal machine comprises a second laser, a second optical fiber circulator, a 1 xM optical switch, a first right-end transceiver, a second right-end transceiver, …, an Mth right-end transceiver, a second optical switch gating control module, a second computer acquisition system and a second photoelectric detector;
a laser output port of the first laser is connected to a first port of the first optical fiber circulator through a single-mode optical fiber, a second port of the first optical fiber circulator is connected to a zero-number optical port of the 1 × N optical switch through a single-mode optical fiber, a first optical port of the 1 × N optical switch is connected to the first left-end transceiver through a single-mode optical fiber, a second optical port of the 1 × N optical switch is connected to the second left-end transceiver through a single-mode optical fiber, and so on, and an N-number optical port of the 1 × N optical switch is connected to the nth left-end transceiver through a single-mode optical fiber; a control signal output port of the first optical switch gating control module is connected with a gating control port of the 1 xN optical switch through a signal line;
A laser output port of the second laser is connected to a first port of the second optical fiber circulator through a single-mode optical fiber, a second port of the second optical fiber circulator is connected to a zero-number optical port of the 1 × M optical switch through a single-mode optical fiber, a first optical port of the 1 × M optical switch is connected to the first right-end transceiver through a single-mode optical fiber, a second optical port of the 1 × M optical switch is connected to the second right-end transceiver through a single-mode optical fiber, and so on, and an M-number optical port of the 1 × M optical switch is connected to the M-th right-end transceiver through a single-mode optical fiber; a control signal output port of the second optical switch gating control module is connected with a gating control port of the 1 xM optical switch through a signal line;
a laser signal emitted by the first laser enters the first optical fiber circulator from a first port of the first optical fiber circulator, is emitted from a second port of the first optical fiber circulator and then reaches the 1 xN optical switch, and finally enters an atmospheric turbulence channel through the left-end transceiver corresponding to an optical port communicated with a zero-number optical port of the 1 xN optical switch; after the laser signal transmitted from the first laser reaches the second space diversity terminal through an atmospheric turbulence channel, the first right-end transceiver, the second right-end transceiver, and so on of the second space diversity terminal receive a part of laser signal; only the laser signal received by the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 × M optical switch can enter the second port of the second optical fiber circulator through the 1 × M optical switch and exit from the third port of the second optical fiber circulator; a laser signal emitted from a third port of the second optical fiber circulator is incident on the second photoelectric detector through a single-mode optical fiber; the second computer acquisition system samples and quantizes the electric signal output by the second photoelectric detector and stores the sampled value in a memory;
A laser signal emitted by the second laser enters the second optical fiber circulator from a first port of the second optical fiber circulator, is emitted from a second port of the second optical fiber circulator and then reaches the 1 xM optical switch, and finally enters an atmospheric turbulence channel through the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xM optical switch; after the laser signal transmitted from the second laser reaches the first space diversity terminal through an atmospheric turbulence channel, the first left-end transceiver, the second left-end transceiver, and so on of the first space diversity terminal receive a part of the laser signal; only the laser signal received by the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch can enter the second port of the first optical fiber circulator through the 1 xN optical switch and exit from the third port of the first optical fiber circulator; a laser signal emitted from a third port of the first optical fiber circulator is incident on the first photoelectric detector through a single-mode optical fiber; the first computer acquisition system samples and quantizes the electric signal output by the first photoelectric detector and stores the sampled value in a memory;
The first optical switch gating control module is arranged at intervals deltatChanging an output control signal to change the optical port connection mode of the 1 × N optical switch once, specifically, randomly selecting an optical port in an equal probability manner from the optical ports of N-1 other optical switches that are not currently connected to the zero-numbered optical port of the 1 × N optical switch, and connecting the selected optical port of the 1 × N optical switch to the zero-numbered optical port of the 1 × N optical switch;
the second optical switch gating control module is arranged at intervals deltatChanging the output control signal to change the optical port communication mode of the 1 × M optical switch once, specifically, randomly selecting one optical port in an equal probability manner from the optical ports of M-1 other 1 × M optical switches that are not currently communicated with the zero-numbered optical port of the 1 × M optical switch, and communicating the selected optical port of the 1 × M optical switch with the zero-numbered optical port of the 1 × M optical switch;
if the optical port communicated with the zero-number optical port of the 1 × N optical switch is the first optical port of the 1 × N optical switch, the left transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 × N optical switch is the first left transceiver; if the optical port communicated with the zero-number optical port of the 1 xN optical switch is the second optical port of the 1 xN optical switch, the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xN optical switch is the second left-end transceiver; by analogy, if the optical port communicated with the zero-number optical port of the 1 × N optical switch is the N-number optical port of the 1 × N optical switch, the left-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 × N optical switch is the nth left-end transceiver;
If the optical port communicated with the zero-number optical port of the 1 xm optical switch is the first optical port of the 1 xm optical switch, the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch is the first right-end transceiver; if the optical port communicated with the zero-number optical port of the 1 xm optical switch is the second optical port of the 1 xm optical switch, the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 xm optical switch is the second right-end transceiver; by analogy, if the optical port communicated with the zero-number optical port of the 1 × M optical switch is the M-number optical port of the 1 × M optical switch, the right-end transceiver corresponding to the optical port communicated with the zero-number optical port of the 1 × M optical switch is the mth right-end transceiver;
obtaining sample values of the received optical signal and extracting random bits requires performing operations S1, S2, and S3;
s1: at slave time tbTo time teAt time intervals δ of said first computer acquisition systemsSampling and quantizing the electric signal output by the first photoelectric detector for one time, and storing a sampling value obtained by performing sampling and quantizing operation each time in a memory of the first computer acquisition system to form a first sampling value sequence; at slave time t bTo time teAt time intervals delta, the second computer acquisition systemsSampling and quantizing the electrical signal output by the second photodetector once, and comparing each timeThe sampling value obtained by executing the sampling and quantization operation is stored in a memory of the second computer acquisition system to form a second sampling value sequence;
s2: the first computer acquisition system extracts NUM bits from the first sampling value sequence, the second computer acquisition system extracts NUM bits from the second sampling value sequence, NUM represents the number of sampling values contained in the first sampling value sequence, and the number of sampling values contained in the first sampling value sequence is equal to the number of sampling values contained in the second sampling value sequence; calculating an empirical cumulative distribution function F of the sample values of the first sample value sequence in the first computer acquisition system taking each sample value of the first sample value sequence as a random observed value1(x) And calculate
Handle Tx1As a decision threshold for extracting a random bit sequence; for the ith sample value of the first sample value sequence, i is 1,2,3, …, NUM, if the ith sample value of the first sample value sequence is greater than T x1If the ith bit extracted from the first sample value sequence by the first computer acquisition system is 1, otherwise, the ith bit extracted from the first sample value sequence by the first computer acquisition system is 0; taking each sample value of the second sample value sequence as a random observed value, and calculating an empirical cumulative distribution function F of the sample values of the second sample value sequence in the second computer acquisition system2(x) And calculate
Handle Tx2As a decision threshold for extracting a random bit sequence; j equals 1,2,3, …, NUM for the j-th sample value of the second sample value sequence, if the j-th sample value of the second sample value sequence is greater than Tx2If the j bit extracted from the second sample value sequence by the second computer acquisition system is 1, otherwise, the second computer acquisition system extracts the second sample value sequence from the second sample value sequenceThe jth bit extracted in (1) is 0;
s3: and correcting inconsistent bits in the bit sequence containing NUM bits extracted by the first computer acquisition system and the bit sequence containing NUM bits extracted by the second computer acquisition system by utilizing error code estimation, key agreement and error check technologies in the processing after quantum key distribution, so that the first computer acquisition system and the second computer acquisition system have the same bit sequence.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011393371.2A CN112491547B (en) | 2020-12-03 | 2020-12-03 | Atmospheric turbulence optical channel shared random bit extraction system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011393371.2A CN112491547B (en) | 2020-12-03 | 2020-12-03 | Atmospheric turbulence optical channel shared random bit extraction system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112491547A CN112491547A (en) | 2021-03-12 |
| CN112491547B true CN112491547B (en) | 2022-06-28 |
Family
ID=74938981
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011393371.2A Active CN112491547B (en) | 2020-12-03 | 2020-12-03 | Atmospheric turbulence optical channel shared random bit extraction system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112491547B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113452524B (en) * | 2021-07-20 | 2022-06-07 | 中南大学 | Free space continuous variable quantum key distribution system based on space diversity technology and implementation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101917244A (en) * | 2002-02-28 | 2010-12-15 | 松下电器产业株式会社 | Communication means, communicator and transceiver |
| CN108683462A (en) * | 2018-07-31 | 2018-10-19 | 深圳大学 | A kind of encryption method and system of free space optical communication data |
| CN110521277A (en) * | 2017-03-22 | 2019-11-29 | 尼克根合伙Ip有限责任公司 | The regeneration and forwarding of millimeter wave for building penetration |
| CN110890917A (en) * | 2019-12-10 | 2020-03-17 | 长春理工大学 | Atmospheric turbulence optical channel shared random bit extraction method based on frequency spectrum domain |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8583067B2 (en) * | 2008-09-24 | 2013-11-12 | Honeywell International Inc. | Apparatus and method for improved wireless communication reliability and performance in process control systems |
| US9560073B2 (en) * | 2011-09-08 | 2017-01-31 | Drexel University | Reconfigurable antenna based solutions for device authentication and intrusion detection in wireless networks |
| KR101740452B1 (en) * | 2013-12-03 | 2017-05-26 | 엘지전자 주식회사 | Apparatus for processing at least one pdu (protocol data unit) in a broadcast system, method for processing at least one pdu (protocol data unit) in a broadcast system |
| CN106788770B (en) * | 2016-12-07 | 2018-12-11 | 长春理工大学 | According to the method for channel status automatic adjusument Atmospheric Laser Communications System transmission power |
| CN109361456B (en) * | 2018-11-20 | 2021-01-01 | 长春理工大学 | Method for measuring signal fluctuation correlation coefficient of bidirectional atmospheric turbulence optical channel |
| CN109474421B (en) * | 2018-11-20 | 2021-04-13 | 长春理工大学 | Method for extracting shared random bit from atmospheric turbulence optical signal fading |
-
2020
- 2020-12-03 CN CN202011393371.2A patent/CN112491547B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101917244A (en) * | 2002-02-28 | 2010-12-15 | 松下电器产业株式会社 | Communication means, communicator and transceiver |
| CN110521277A (en) * | 2017-03-22 | 2019-11-29 | 尼克根合伙Ip有限责任公司 | The regeneration and forwarding of millimeter wave for building penetration |
| CN108683462A (en) * | 2018-07-31 | 2018-10-19 | 深圳大学 | A kind of encryption method and system of free space optical communication data |
| CN110890917A (en) * | 2019-12-10 | 2020-03-17 | 长春理工大学 | Atmospheric turbulence optical channel shared random bit extraction method based on frequency spectrum domain |
Non-Patent Citations (2)
| Title |
|---|
| "Modal diversity for robust free-space optical communications";Mitchell Arij Cox;《Physical Review Applied》;20181001;全文 * |
| "基于OCDMA的混合FSO/光纤搭线信道物理层安全分析及实验研究";黄倩;《中国优秀硕士学位论文全文数据库》;20200915;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112491547A (en) | 2021-03-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112491547B (en) | Atmospheric turbulence optical channel shared random bit extraction system | |
| CN110890917B (en) | Atmospheric turbulence optical channel shared random bit extraction method based on frequency spectrum domain | |
| CN112039919B (en) | Atmospheric turbulence optical channel shared random bit extraction method based on frequency equalization | |
| Takeda et al. | Analysis of CDMA systems that are characterized by eigenvalue spectrum | |
| CN114422119B (en) | Atmospheric optical channel key extraction method for realizing decorrelation of measurement samples based on random modulation | |
| CN102882631A (en) | Optical code demultiplexing/multiplexing sending and receiving method and device based on electric domain encoding/decoding | |
| CN105162556A (en) | Large-scale MIMO system channel feedback method based on spatial- temporal correlation | |
| CN112491546B (en) | Method for extracting shared random bits of atmospheric turbulence optical channel | |
| US20080077343A1 (en) | Implementation of coded optical time-domain reflectometry | |
| Wen et al. | Modified prime-hop codes for optical CDMA systems | |
| US20040213586A1 (en) | Method and apparatus for data recovery in an optical transmission system | |
| CN107181705A (en) | A kind of half-blind channel estimating method and system | |
| CN101068136B (en) | Optical communication multichannel multiplexing method and system based on chromatic dispersion matching | |
| CN109361456B (en) | Method for measuring signal fluctuation correlation coefficient of bidirectional atmospheric turbulence optical channel | |
| Gao et al. | A machine learning assisted device fingerprint identification technique for TDM-PON system | |
| CN100571091C (en) | A kind of pilot capture method and device based on the schizotype matched filter | |
| Sone et al. | Implementation of Rx-side DSP-based fiber-longitudinal optical power profile monitoring for optical network tomography | |
| Kahn et al. | Mode-division multiplexing systems: Propagation effects, performance and complexity | |
| Cao et al. | Free space optical MIMO system using PPM modulation and a single optical amplifier | |
| CN1529525A (en) | Device and method for detecting defined frame synchronization of channel contour window | |
| CN101383677B (en) | Star type optical fiber grating sensing network based on CDMA multiplexing and demodulation method | |
| Yuan et al. | Based on cross-correlation function OSNR monitoring technique for PM-QPSK system in presence of fiber nonlinearities | |
| Jin et al. | Analysis of encoding and decoding method of underwater OCDMA system based on decreasing code weight OOC code | |
| Vardakas et al. | A multi-rate loss model for OCDMA PONs | |
| Kumar et al. | CTH01-5: A novel optical CDMA modulation scheme: Code cycle modulation |
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 |