CN108964778A - It is a kind of for time bit-phase code decoding apparatus - Google Patents
It is a kind of for time bit-phase code decoding apparatus Download PDFInfo
- Publication number
- CN108964778A CN108964778A CN201710365576.1A CN201710365576A CN108964778A CN 108964778 A CN108964778 A CN 108964778A CN 201710365576 A CN201710365576 A CN 201710365576A CN 108964778 A CN108964778 A CN 108964778A
- Authority
- CN
- China
- Prior art keywords
- time
- basic vector
- interferometer
- phase
- photodetector
- 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.)
- Pending
Links
Classifications
-
- 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
- H04B10/508—Pulse generation, e.g. generation of solitons
-
- 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
- H04B10/516—Details of coding or modulation
- H04B10/548—Phase or frequency modulation
- H04B10/556—Digital modulation, e.g. differential phase shift keying [DPSK] or frequency shift keying [FSK]
- H04B10/5561—Digital phase modulation
-
- 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
- H04B10/60—Receivers
- H04B10/61—Coherent receivers
- H04B10/615—Arrangements affecting the optical part of the receiver
- H04B10/6151—Arrangements affecting the optical part of the receiver comprising a polarization controller at the receiver's input stage
-
- 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
- H04B10/60—Receivers
- H04B10/66—Non-coherent receivers, e.g. using direct detection
- H04B10/69—Electrical arrangements in the receiver
- H04B10/691—Arrangements for optimizing the photodetector in the receiver
Abstract
It is disclosed in the embodiment of the present invention a kind of for time bit-phase code decoding apparatus, comprising: unequal arm Michelson's interferometer, two photodetectors, decoding unit and circulator；Unequal arm Michelson's interferometer includes beam splitter and two reflecting mirrors, two reflecting mirrors connect and compose the long-armed and galianconism of interferometer with beam splitter respectively, and the time interval between the corresponding time difference of the arm length difference of unequal arm Michelson's interferometer and 2 time mode light pulses of phase basic vector is consistent；Two photodetectors are separately connected two output ports of unequal arm Michelson's interferometer；Decoding unit connects two photodetectors, and the decoding under phase basic vector and/or time basic vector is carried out according to the output of photodetector；Circulator is connected with the input port of decoding apparatus, an output port of unequal arm Michelson's interferometer and a photodetector.Solve the problems, such as that polarization existing in the prior art is related, Insertion Loss is high, system complex and at high cost.
Description
Technical field
The present invention relates to Technique on Quantum Communication fields, and in particular to a kind of to fill for the decoding of time bit-phase code
It sets.
Background technique
Forward position of the quantum secret communication as contemporary communication technical field, development are maked rapid progress, and are led to relative to traditional
For letter technology, the absolute safety of communication ensure that from principle, this is that conventional communication techniques cannot be unmatch.Quantum
In secret communication field, most widely used, development most mature is exactly quantum key distribution direction.Quantum key distribution is utilized
The basic principles such as quantum in quantum mechanics is not reproducible, use the mode of " one-time pad " to encrypt information, are highly suitable for
To the higher national defence unit of confidentiality requirement, government bodies, R&D institution, financial institution etc..
At present in the encoding scheme of quantum key distribution, relatively conventional is polarization encoder and phase encoding scheme.Polarization
The encoding scheme that encoding scheme proposed earliest as 1984 has the advantages that receiving end Insertion Loss is low, at low cost and structure is simple,
So be at present main coding mode, and its disadvantage is that polarized systems are easy to be influenced by optical fiber polarisation disturbance, direct shadow
It rings and needs frequent starting polarization feedback or the fast control bit error rate of module partially of needs under its bit error rate, especially aerial optical cable environment
It could be at code to normal level.And these factors also result in it is temporal waste so that at code rate reduce or it is unstable.
Compared to polarization encoder, the situation that the application scenarios of phase code are relatively suitble to polarization variations more violent, phase
Encoding scheme prepares light pulse by unequal arm interferometer, using the phase difference of front and back light pulse as information carrier, and optical fiber
Influence of the polarization variations to phase difference it is smaller, therefore polarization variations not will cause bit error rate rising, and at most to receive to count
Digit rate decline.This would indicate that biggish advantage in the environment for transmitting at a distance or having strong external interference.However its disadvantage
Very big for the receiving end Insertion Loss of conventional phase system, the receiving end than polarization encoder system increases at least 3dB.And become in polarization
Change relatively acutely in the case where, receive loss further increase 3dB, cause into code rate and farthest at code distance lower than polarization system
System, it is different to be surely advantageously applied to long range aerial optical cable environment.
Under the premise of herein, there has been proposed time bit-phase code schemes.Its transmitting terminal and the coding of receiving end and
2 groups of targeted basic vectors of decoding design are time basic vector and phase basic vector, namely are as follows: Z basic vector (eigenstate is | t0>、|t1>), and
(eigenstate is X (or Y) basic vector(or)).This
In, | t0>、|t1> indicate 2 different time modes, namely be complete nonoverlapping mode both from time shaft.Fig. 1
Show the X basic vector and Z basic vector in time bit-phase code.
Fig. 2 shows a kind of based on time bit-PE system decoding end structure of the prior art, wherein needle
Decoding to Z basic vector is unrelated with polarization, and in terms of X basic vector decoding, then it is using optical planar circuit technology (PLC) in silicon substrate
Asymmetric mach Zeng Deer (MZ) interference system is made by optical waveguide that patterning is formed on plate to execute.As shown in Fig. 2,
The light pulse signal that coding side generates first passes around a beam splitter and can be under its effect after transmission reaches decoding end
Into Z basic vector decoded portion or enter X basic vector decoded portion.In Z basic vector decoded portion, based on the difference of time location come
Realize the decoding to Z basic vector；In X basic vector decoded portion, pass through the asymmetric mach Zeng Deer interference system formed by PLC technology
System to X basic vector to be decoded.In this X basic vector decoded portion, to achieve the effect that the unrelated needs of polarization are extremely complex
Control process, such as need to carry out high-precision control to parameters such as temperature.In decoding end structure shown in Fig. 2,
X basic vector decoded portion can also be realized simply by optical fibre device, being formed by the part-structure at this time can be equivalent to
MZ interferometer, and this optical fiber MZ interferometer be it is relevant to polarization, need to polarize feedback.In addition, this X basic vector decoded portion
In, there are non-interference portions in result of interference, and non-interference portion proportion is 50%, this results in this X basic vector to decode
There are intrinsic 3dB decodings to be lost in part.
Fig. 3 show another prior art based on time bit-PE system decoding end structure, be used for
Receive the signal pulse of first latter two different polarization states (horizontal and vertical polarization state).In the decoding end structure, two are not
Signal pulse with polarization state successively reaches polarization beam apparatus 22 and being divided into two-way according to the difference of polarization state has difference inclined
The light of polarization state, such as: orthogonal polarized light is reflected to be exported by port 22C, again through Faraday rotation after the delay of delay line 24
Mirror 25 is changed into horizontal polarization light and is back to polarization beam apparatus along original optical path, is transmitted and is exported by port 22B；Horizontal polarization light
It is projected and is exported through port 22D, be changed into orthogonal polarized light by faraday rotation mirror 26 and be back to polarization point along original optical path
Beam device is equally exported by port 22B after reflection.Wherein, by the setting of delay line 24 so that two-way has different polarization states
Light by port 22B output after is formed in time unanimously, then by λ/2Wave plate adjusts polarization direction and at polarization beam apparatus 27
It interferes, result of interference is finally measured by photodetector 13 and 14, to complete the decoding of X basic vector.In this solution
In code end structure, the problem of being lost, but bringing to avoid caused by non-interference portion, needs to this phase system
Polarization is fed back, and when (such as aerial optical cable, high-speed rail route) is difficult to carry out polarization feedback in the presence of a harsh environment, it equally has non-
Interference portion causes to be lost.In addition, transmission channel is also inconsistent to the phase change of different polarization states under varying environment, phase states
2 pulses between phase it is affected by environment, cause the rate request to phase feedback very high, or variation adverse circumstances
Have little time phase feedback at all down, to allow phase states bit error rate severe exacerbation.
Therefore, related, slotting for the existing polarization of time bit-phase encoding scheme decoding end structure in the prior art
Damage is high, system complex and it is at high cost the problems such as, become current urgent problem to be solved.
Summary of the invention
In view of this, the embodiment of the present invention provides a kind of for time bit-phase code decoding apparatus, it is able to solve
In the prior art for the existing polarization of time bit-phase encoding scheme decoding end structure to be related, Insertion Loss is high, system complex
And the problems such as at high cost.
To achieve the above object, the embodiment of the present invention provides the following technical solutions:
It is a kind of for time bit-phase code decoding apparatus, comprising: unequal arm Michelson's interferometer, two light
Electric explorer, decoding unit and circulator；
The unequal arm Michelson's interferometer includes beam splitter and two reflecting mirrors, described two reflecting mirrors respectively with institute
Beam splitter connection is stated to constitute the long-armed and galianconism of the interferometer, the arm length difference of the unequal arm Michelson's interferometer is corresponding
Time difference it is consistent with the time interval between 2 time mode light pulses of phase basic vector；
Described two photodetectors are separately connected two output ports of the unequal arm Michelson's interferometer；
The decoding unit connects described two photodetectors, to be carried out according to the output of described two photodetectors
Decoding under the phase basic vector and/or time basic vector；
The circulator and input port, the unequal arm for time bit-phase code decoding apparatus
One output port of Michelson's interferometer and a photodetector are connected.
Preferably, the circulator includes:
First, second, and third port, the input port for time bit-phase code decoding apparatus is successively
It is connected via the first port and the second port with the unequal arm Michelson's interferometer, the unequal arm Michael
One in the output port of inferior interferometer successively via the second port and the third port and the photodetector
In one be connected.
Preferably, decoding unit is configured to, and two photodetectors are detected within a system period first, second
With the output on third time window, wherein first, second, and third time window is in time successively rearward.
Preferably, described to be configured to for time bit-phase code decoding apparatus, according in second time
The photodetector of interference light signal is detected on window to carry out phase basic vector decoding；
Or；
It is described to be configured to for time bit-phase code decoding apparatus, according to described two photodetectors
The position of time window corresponding to output in relation to non-interfering optical signal carries out time basic vector decoding.
Preferably, reflecting mirror includes: faraday rotation mirror；
In the unequal arm Michelson's interferometer further include: phase shifter.
It is a kind of for time bit-phase code decoding apparatus, comprising: basic vector alternative pack, phase basic vector lsb decoder
Divide, time basic vector decoded portion and circulator, the basic vector alternative pack are used to be arrived basic vector pulse input according to predetermined probabilities
One in the phase basic vector decoded portion and the time basic vector decoded portion；
The time basic vector decoded portion includes the first photodetector and time basic vector decoding unit section, the time
Basic vector decoding unit section connects first photodetector to carry out the time according to the output of first photodetector
Basic vector decoding；
The phase basic vector decoded portion include unequal arm Michelson's interferometer, second and third photodetector and
Phase basic vector decoding unit section, the phase basic vector decoding unit section connection described second and third photodetector, with
The decoding of phase basic vector is carried out according to the output of described second and third photodetector；
The interferometer includes beam splitter and two reflecting mirrors, described two reflecting mirrors connect respectively with the beam splitter with
The long-armed and galianconism of the interferometer is constituted, at 2 of the corresponding time difference of the arm length difference of the interferometer and phase basic vector
Between time interval between mode light pulse it is consistent；And
Described second and third photodetector be separately connected two output ports of the interferometer；
The circulator and input port, the unequal arm for time bit-phase code decoding apparatus
One output port of Michelson's interferometer and a photodetector are connected.
Preferably, the circulator includes: the first, second, and third port, the output port of the basic vector alternative pack
Successively it is connected via the first port and the second port with the interferometer, in the output port of the interferometer
One successively via the second port and the third port and a phase in described second and third photodetector
Even.
Preferably, the phase basic vector decoding unit section is configured to, and detects described second within a system period
With output of the third photodetector on the second time window；
The time basic vector decoding unit section is configured to, and first photodetection is detected within a system period
Output of the device on first and second time window；
First and second time window is in time successively rearward.
Preferably, the phase basic vector decoding unit section is configured to, and is detected according on second time window
Photodetector to interference light signal carries out the decoding of phase basic vector；
Alternatively, the time basic vector decoding unit section is configured to, light is detected according to first photodetector
The position of the time window of signal carries out time basic vector decoding.
Preferably, reflecting mirror includes: faraday rotation mirror；
In the unequal arm Michelson's interferometer further include: phase shifter.
Based on the above-mentioned technical proposal, it is disclosed in the embodiment of the present invention a kind of for the decoding of time bit-phase code
Device, comprising: unequal arm Michelson's interferometer, two photodetectors, decoding unit and circulator；The unequal arm mikey
Your inferior interferometer includes beam splitter and two reflecting mirrors, and described two reflecting mirrors connect with the beam splitter described to constitute respectively
The long-armed and galianconism of interferometer, the corresponding time difference of arm length difference and the phase basic vector of the unequal arm Michelson's interferometer
Time interval between 2 time mode light pulses is consistent；Described two photodetectors are separately connected the unequal arm mikey
Two output ports of your inferior interferometer；The decoding unit connects described two photodetectors, according to described two light
The output of electric explorer carries out the decoding under the phase basic vector and/or time basic vector；The circulator is used for the time with described
The input port of bit-phase code decoding apparatus, the unequal arm Michelson's interferometer an output port and
One photodetector is connected.It is able to solve and is deposited in the prior art for time bit-phase encoding scheme decoding end structure
Polarization it is related, Insertion Loss is high, system complex and it is at high cost the problems such as.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
The embodiment of invention for those of ordinary skill in the art without creative efforts, can also basis
The attached drawing of offer obtains other attached drawings.
Fig. 1 is X basic vector and Z basic vector schematic diagram in the time bit-phase code provided in the prior art；
Fig. 2 is a kind of based on time bit-PE system decoding end structural schematic diagram of the prior art；
Fig. 3 is another prior art based on time bit-PE system decoding end structural schematic diagram；
Fig. 4 is showing for time bit-phase code decoding apparatus structure for the first exemplary embodiment of the invention
It is intended to；
Fig. 5 shows the decoding principle schematic diagram for time bit-phase code decoding apparatus of Fig. 4；
Fig. 6 shows another kind of the invention for time bit-phase code decoding apparatus structural schematic diagram；
The another kind that Fig. 7 shows Fig. 6 is used for the time basic vector decoding principle of time bit-phase code decoding apparatus
Schematic diagram；
The another kind that Fig. 8 shows Fig. 6 is used for the phase basic vector decoding principle of time bit-phase code decoding apparatus
Schematic diagram.
Specific embodiment
Hereinafter, exemplary embodiment of the present invention is with reference to the accompanying drawings to detailed description.The following examples are to illustrate
Mode provide, sufficiently to convey spirit of the invention to those skilled in the art in the invention.Therefore, the present invention is unlimited
In embodiment disclosed herein.
For being deposited in the decoding apparatus using time bit-phase encoding scheme trick state BB84 system of the prior art
High Insertion Loss, polarization is related, system complex and it is at high cost the problems such as, the invention proposes a kind of new particularly suitable for time ratio
Spy-phase encoding scheme decoding apparatus, can not only realize the measurement unrelated with polarizing, and can be effectively reduced decoding
Loss, realizes the promotion of decoding efficiency.
Fig. 4 schematically illustrates the decoding apparatus of the first exemplary embodiment of the invention, of the invention for illustrating
Decoding principle.As shown in figure 4, the decoding apparatus may include circulator 1, unequal arm Michelson's interferometer, photodetector
4-1 and 4-2 and decoding unit (not shown).Unequal arm Michelson's interferometer may include that beam splitter (BS) 2 and two are anti-
Penetrate mirror 3-1,3-2, wherein beam splitter 2 port 2B and reflecting mirror 3-1 constitute interferometer it is long-armed, the port 2C of beam splitter 2 with
Reflecting mirror 3-2 constitutes the galianconism of interferometer, and the long-armed arm length difference between galianconism can be configured to 2 times with X basic vector
Time interval between mode light pulse is consistent.The port 2A of the port 1B connection beam splitter 2 of circulator 1, circulator 1
Port 1C connection photodetector D4-1, the port 2D connection detector D4-2 of beam splitter 2.Decoding unit and photodetector
D4-1 is connected with D4-2 to receive the output signal from photodetector, to carry out the decoding of Z basic vector and X basic vector.
Fig. 5 illustrates that the decoding apparatus of Fig. 4 carries out the principle of X basic vector and Z basic vector.
Within a system period, when former and later two continuous time mode light pulses of X basic vector enter decoding apparatus, by
The port 1A of circulator enters and exports from port 1B to beam splitter 2, enters respectively from port 2B and 2C after 2 beam splitting of beam splitter
The long-armed and galianconism of interferometer, and port 2B and 2C are returned after reflecting mirror 3-1 and 3-2 reflection respectively.Since unequal arm is interfered
The long-armed arm length difference between galianconism of instrument is configured to the guarantor of the time interval between 2 time mode light pulses of X basic vector
It holds unanimously, therefore continuous two light pulses for being returned on long-armed and galianconism through reflecting mirror reflection, the previous light on galianconism
Pulse first time reach beam splitter 2, the latter light pulse the second time reach beam splitter 2, it is long-armed on previous light
Pulse reaches beam splitter 2 in the second time, and the latter light pulse reaches beam splitter 2 in the third time, wherein at the first time < second
Time < third time.It is concerned with it can be seen that will occur two on the second time within a system period, on beam splitter 2
Light pulse, and the two coherent optical pulses correspond to former and later two continuous time mode light pulses of X basic vector, exist between them
Phase difference relationship relevant to coding.Therefore, when the phase difference between former and later two continuous light pulses of X basic vector be 0 when (such as
It represents coding 0), result of interference will be exported at the 2A of port on the second time, correspondingly, photodetector D4-1 is corresponding to
A stronger interference light signal is received on the second time window t01 of second time, photodetector D4-2 is in time window
Optical signal is not received on mouth t01；It, will be defeated at the 2D of port on the second time when phase difference is π (such as representing coding 1)
Result of interference out, i.e. photodetector D4-2 receive a stronger optical signal, photodetection on the second time window t01
Device D4-1 does not receive optical signal on the second time window t01.In addition, in the first time window for corresponding to first time
On t00, photodetector D4-1 and D4-2 are likely to be received what previous light pulse on galianconism exported after 2 beam splitting of beam splitter
Optical signal；On the third time window t02 for corresponding to the third time, photodetector D4-1 and D4-2 are likely to be received length
The optical signal that the latter light pulse exports after beam splitter beam splitting on arm.It can be seen that in decoding apparatus shown in Fig. 4, when
When carrying out the decoding of X basic vector, within a system period, one in photodetector D4-1 and D4-2 will be in t00, t01 and t02
It is likely to be received optical signal on three time windows, wherein the optical signal on t01 time window is interference signal, t01 and t02
Optical signal on time window is non-interfering signal.Detection result of the photodetector on t01 time window corresponds to X base
Encoded radio under arrow.For example, can indicate X base when photodetector D4-1 detects interference signal on t01 time window
The coding 0 of arrow；Vice versa.
Within a system period, when a light pulse under Z basic vector enters decoding apparatus, by the port 1A of circulator
Export to beam splitter 2 into and from port 1B, after 2 beam splitting of beam splitter respectively from port 2B and 2C enter the long-armed of interferometer and
Galianconism, and port 2B and 2C are returned after reflecting mirror 3-1 and 3-2 reflection respectively.Since the arm length difference of unequal arm interferometer is arranged,
If the time location of the light pulse of the Z basic vector preceding (such as representing time encoding 0), galianconism and it is long-armed on light pulse will
Respectively at the first time and the second time reached beam splitter 2, correspondingly, detector D4-1 or D4-2 will respectively have half probability the
Optical signal is detected on one time window t00 and the second time window t01.First time window t00 is non-interfering window, is Z
Basic vector detection window.If the time location of the light pulse of the Z basic vector is in rear (such as representing time encoding 1), galianconism and length
Light pulse on arm will reach beam splitter 2 in the second time and third time respectively, and correspondingly, detector D4-1 or D4-2 will be each
There is half probability to detect optical signal on the second time window t01 and third time window t02, third time window t02 is
Non-interfering window is also Z basic vector detection window.It can be seen that in decoding apparatus shown in Fig. 4, when progress Z basic vector decoding
When, within a system period, one of two photodetectors have in non-interfering time window namely Z basic vector detection window
The position t00 and t02 of two time windows of detection, correspond respectively to the encoded radio under Z basic vector.For example, photodetector D4-
1 or D4-2 has detection in first time window t00, then it represents that the coding 0 of Z basic vector；When photodetector D4-1 or D4-2 third
Between have detection on window t02, then it represents that the coding 1 of Z basic vector.
Based on above-mentioned decoding principle, in the decoding apparatus of Fig. 4, decoding unit can be configured to, a system week
Detection of two photodetector D4-1 and D4-2 on first, second, and third time window t00, t01 and t02 is received in phase
As a result, in which: for X basic vector, decoded according to the photodetector of interference light signal is detected on the second time window；It is right
In Z basic vector, solved according to there is the position of continuous two time windows of non-interfering signal on two photodetectors simultaneously
Code.
In this illustrative decoding apparatus of the invention, use by beam splitter (non-polarizing beamsplitter) and reflecting mirror
The Michelson unequal arm interferometer built realizes and polarizes completely irrelevant measurement, greatlies simplify decoding knot
Structure reduces cost；By innovative decoding principle, based on the analysis of the detection result on specific three time windows, only
Z basic vector and X basic vector can be realized by same optical texture simultaneously by the combination of unequal arm interferometer and two photodetectors
Decoding, the structure of simple knowledge code device, at the same by non-interfering signal section be applied to decoding in, realize lossless solution
Code, thus improve system at code rate, at code distance, enable decoding apparatus to better adapt to long range aerial optical cable ring
Border.
Fig. 6 schematically illustrates the decoding apparatus of the second exemplary embodiment of the invention, the structure phase with Fig. 4
Than increasing and being provided with a basic vector alternative pack 5 and photodetector D4-0.Wherein, circulator 1, unequal arm interferometer, photoelectricity
Detector D4-1, D4-2 and corresponding decoding unit part are used as X basic vector decoded portion, photodetector D4-0 and corresponding decoding
Unit part is used as Z basic vector decoded portion, and basic vector alternative pack 5 is used to be inputted light pulse to be decoded according to predetermined probabilities
Into X basic vector decoded portion or Z basic vector decoded portion to be decoded under corresponding basic vector.
Fig. 7 schematically illustrates the decoding process and principle of Z basic vector decoded portion.As shown in fig. 7, a system week
In phase, when two time mode light pulses under basic vector alternative pack 5 allows X basic vector enter Z basic vector decoded portion, no matter this two
Phase difference between a light pulse is 0 or π (i.e. X basic vector is encoded to 0 or 1), and photodetector D4-0 is possible to first
Optical signal is received on time window t00 or the second time window t01, it means that Z basic vector decoded portion can not achieve X basic vector
Decoding.When a time mode light pulse under basic vector alternative pack 5 allows Z basic vector enters Z basic vector decoded portion, if should
The time location of the light pulse of Z basic vector is preceding (such as representing time encoding 0), then detector D4-0 will be only in first time window
T00 detects optical signal；If the time location of light pulse is rear (such as representing time encoding 1), detector D4-0 will only
Optical signal is detected on the second time window t01.In other words, within a system period, photodetector D4-0 is detected
The time window position of light, corresponding to the encoded radio under Z basic vector.For example, optical signal is detected on first time window t00,
Then indicate the coding 0 of Z basic vector；Optical signal is detected on the second time window t01, then it represents that the coding 1 of Z basic vector.
Fig. 8 correspond to X basic vector decoded portion decoding process and principle it is similar with embodiment illustrated in fig. 4, therefore herein not
It repeats again.Need herein it is especially mentioned that, since X basic vector decoded portion is only used for decoding under X basic vector herein, only
Detector position by detecting interference signal on the second time window t01 can embody the difference of X basic vector coding, for example,
Detector D4-1 detects interference signal on the second time window t01, it can represents X basic vector coding 0；Detector D4-2 exists
Interference signal is detected on second time window t01, it can represents X basic vector coding 1.
Therefore, in the decoding apparatus of Fig. 6, decoding unit can be configured to, and three are received within a system period
The detection result of photodetector D4-0, D4-1 and D4-2 on the first and second time window t00 and t01, in which: for X
Basic vector is decoded according to the photodetector of interference light signal is detected on t01 time window；For Z basic vector, according to photoelectricity
Detector D4-0 detects the time window position of optical signal to decode.
In this illustrative decoding apparatus of the invention, what is be identical with the first embodiment is equally to realize and polarize
Completely irrelevant measurement, the difference is that: it, will be by first within a system period in decoding structure shown in Fig. 4
Detection result on to third totally three time windows realizes the decoding of X basic vector and Z basic vector, and fills in the decoding of the present embodiment
In setting, only need to realize X base by the detection result on first and second totally two time windows within a system period
The decoding of resultant Z basic vector, due to decoding need time window quantity reduce, it is therefore desirable to decoding periods shorten, detection
Time efficiency can be higher.However, compared to first embodiment, the relatively short detection cycle of the present embodiment, reached compared with
High detection time efficiency, and inherent loss is not present in Z basic vector decoded portion, losslessly encoding, but X basic vector solution can be provided
There are intrinsic 3dB losses for code, can be by by the Z basic vector and X of basic vector alternative pack in this regard, in order to reduce decoding inherent loss
The likelihood ratio of basic vector improves, to reduce X basic vector decoded portion bring loss in efficiency, improves the whole efficiency of decoding apparatus.
Optionally, basic vector alternative pack can be beam splitter.
Preferably, in the present invention (such as Fig. 4 or decoding apparatus shown in fig. 6), can also be by reflecting mirror 3-1 and 3-2
It is set as faraday rotation mirror, because of the random variation of polarization state caused by birefringence effect when eliminating using single mode optical fiber,
To guarantee the interference contrast in the decoding of X basic vector.
Preferably, in the present invention (such as Fig. 4 or decoding apparatus shown in fig. 6), can also be in unequal arm interferometer
Phase shifter is set, to provide compensation to possible phase drift.
Those skilled in the art, but can be not it will be appreciated that the invention is not limited to above-mentioned specific embodiments
Various modifications and variation are carried out in the case where being detached from present inventive concept.
Claims (10)
1. a kind of for time bit-phase code decoding apparatus characterized by comprising unequal arm Michelson interference
Instrument, two photodetectors, decoding unit and circulator；
The unequal arm Michelson's interferometer includes beam splitter and two reflecting mirrors, described two reflecting mirrors respectively with described point
Beam device is connected to constitute the long-armed and galianconism of the interferometer, when the arm length difference of the unequal arm Michelson's interferometer is corresponding
Between time interval between difference and 2 time mode light pulses of phase basic vector it is consistent；
Described two photodetectors are separately connected two output ports of the unequal arm Michelson's interferometer；
The decoding unit connects described two photodetectors, according to the output of described two photodetectors progress
Decoding under phase basic vector and/or time basic vector；
The circulator and the input port for time bit-phase code decoding apparatus, the unequal arm mikey
One output port of your inferior interferometer and a photodetector are connected.
2. being used for time bit-phase code decoding apparatus as described in claim 1, which is characterized in that the circulator
Include:
First, second, and third port, the input port for time bit-phase code decoding apparatus successively via
The first port and the second port are connected with the unequal arm Michelson's interferometer, and the unequal arm Michelson is dry
One in the output port of interferometer successively via in the second port and the third port and the photodetector
One is connected.
3. being used for time bit-phase code decoding apparatus as claimed in claim 1 or 2, which is characterized in that decoding unit
It is configured to, output of two photodetectors on the first, second, and third time window is detected within a system period,
Wherein first, second, and third time window is in time successively rearward.
4. as claimed in claim 3 be used for time bit-phase code decoding apparatus, which is characterized in that it is described for when
Between bit-phase code decoding apparatus be configured to, detect interference light signal according on second time window
Photodetector carries out phase basic vector decoding；
Or；
According to the position of time window corresponding to the output of the related non-interfering optical signal of described two photodetectors come into
The decoding of row time basic vector.
5. being used for time bit-phase code decoding apparatus as claimed in claim 4, which is characterized in that reflecting mirror includes:
Faraday rotation mirror；
In the unequal arm Michelson's interferometer further include: phase shifter.
6. a kind of for time bit-phase code decoding apparatus characterized by comprising basic vector alternative pack, phase base
Swear decoded portion, time basic vector decoded portion and circulator, the basic vector alternative pack is used for basic vector arteries and veins according to predetermined probabilities
Rush one be input in the phase basic vector decoded portion and the time basic vector decoded portion；
The time basic vector decoded portion includes the first photodetector and time basic vector decoding unit section, the time basic vector
Decoding unit section connects first photodetector to carry out time basic vector according to the output of first photodetector
Decoding；
The phase basic vector decoded portion includes unequal arm Michelson's interferometer, second and third photodetector and phase
Basic vector decoding unit section, the phase basic vector decoding unit section connection described second and third photodetector, with basis
Described second and third photodetector output carry out the decoding of phase basic vector；
The interferometer includes beam splitter and two reflecting mirrors, and described two reflecting mirrors are connect respectively with the beam splitter to constitute
The long-armed and galianconism of the interferometer, 2 time moulds of the corresponding time difference of the arm length difference of the interferometer and phase basic vector
Time interval between formula light pulse is consistent；And
Described second and third photodetector be separately connected two output ports of the interferometer；
The circulator and the input port for time bit-phase code decoding apparatus, the unequal arm mikey
One output port of your inferior interferometer and a photodetector are connected.
7. being used for time bit-phase code decoding apparatus as claimed in claim 6, which is characterized in that the circulator
It include: the first, second, and third port, the output port of the basic vector alternative pack is successively via the first port and described
Second port is connected with the interferometer, and one in the output port of the interferometer is successively via the second port
It is connected with the third port with one in described second and third photodetector.
8. as claimed in claims 6 or 7 be used for time bit-phase code decoding apparatus, which is characterized in that
The phase basic vector decoding unit section is configured to, and described second and the spy of third photoelectricity are detected within a system period
Survey output of the device on the second time window；
The time basic vector decoding unit section is configured to, and first photodetector is detected within a system period and is existed
Output on first and second time window；
First and second time window is in time successively rearward.
9. being used for time bit-phase code decoding apparatus as claimed in claim 8, which is characterized in that the phase base
Arrow decoding unit section is configured to, according to detected on second time window photodetector of interference light signal into
The decoding of row phase basic vector；
Or；
The time basic vector decoding unit section is configured to, and the time of optical signal is detected according to first photodetector
The position of window carries out time basic vector decoding.
10. being used for time bit-phase code decoding apparatus as claimed in claim 9, which is characterized in that reflecting mirror packet
It includes: faraday rotation mirror；
In the unequal arm Michelson's interferometer further include: phase shifter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710365576.1A CN108964778A (en) | 2017-05-22 | 2017-05-22 | It is a kind of for time bit-phase code decoding apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710365576.1A CN108964778A (en) | 2017-05-22 | 2017-05-22 | It is a kind of for time bit-phase code decoding apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108964778A true CN108964778A (en) | 2018-12-07 |
Family
ID=64463080
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710365576.1A Pending CN108964778A (en) | 2017-05-22 | 2017-05-22 | It is a kind of for time bit-phase code decoding apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108964778A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110752922A (en) * | 2019-10-24 | 2020-02-04 | 四川航天系统工程研究所 | Decoder and time coding quantum key distribution decoding method |
| JPWO2020189348A1 (en) * | 2019-03-18 | 2020-09-24 | ||
| CN113114355A (en) * | 2021-06-15 | 2021-07-13 | 国开启科量子技术(北京)有限公司 | Method and apparatus for detecting quantum communication system |
| WO2021199027A1 (en) | 2020-04-02 | 2021-10-07 | Lidwave Ltd. | Method and apparatus for mapping and ranging based on coherent-time comparison |
| CN114613234A (en) * | 2020-12-08 | 2022-06-10 | 科大国盾量子技术股份有限公司 | Quantum communication attack and defense demonstration system based on photon number separation |
| CN114629629A (en) * | 2020-12-14 | 2022-06-14 | 科大国盾量子技术股份有限公司 | Receiving device, QKD system and quantum communication method |
| CN114629629B (en) * | 2020-12-14 | 2024-04-30 | 科大国盾量子技术股份有限公司 | Receiving device, QKD system and quantum communication method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4907886A (en) * | 1987-04-28 | 1990-03-13 | Wild Heerburgg, Ag | Method and apparatus for two-wavelength interferometry with optical heterodyne processes and use for position or range finding |
| US20100002881A1 (en) * | 2006-12-05 | 2010-01-07 | Chun Ju Youn | Polarization-insensitive one-way quantum key distribution receiver, transmitter/receiver system |
| CN105022606A (en) * | 2015-06-30 | 2015-11-04 | 中国科学技术大学先进技术研究院 | Ultra-high-speed quantum random number generator and generation method based on laser phase fluctuation |
| CN105897414A (en) * | 2016-05-26 | 2016-08-24 | 安徽问天量子科技股份有限公司 | Continuous variable quantum key distribution system based on Faraday-Michelson interference |
| CN106161011A (en) * | 2016-08-19 | 2016-11-23 | 浙江神州量子网络科技有限公司 | A kind of plug and play quantum key dissemination system based on coding time phase and method and transmitting terminal and receiving terminal |
| CN106533676A (en) * | 2016-12-22 | 2017-03-22 | 浙江神州量子网络科技有限公司 | Quantum key distribution system based on reference system independent protocol |
| CN206790495U (en) * | 2017-05-22 | 2017-12-22 | 中国科学技术大学 | A kind of decoding apparatus for time bit phase coding |
-
2017
- 2017-05-22 CN CN201710365576.1A patent/CN108964778A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4907886A (en) * | 1987-04-28 | 1990-03-13 | Wild Heerburgg, Ag | Method and apparatus for two-wavelength interferometry with optical heterodyne processes and use for position or range finding |
| US20100002881A1 (en) * | 2006-12-05 | 2010-01-07 | Chun Ju Youn | Polarization-insensitive one-way quantum key distribution receiver, transmitter/receiver system |
| CN105022606A (en) * | 2015-06-30 | 2015-11-04 | 中国科学技术大学先进技术研究院 | Ultra-high-speed quantum random number generator and generation method based on laser phase fluctuation |
| CN105897414A (en) * | 2016-05-26 | 2016-08-24 | 安徽问天量子科技股份有限公司 | Continuous variable quantum key distribution system based on Faraday-Michelson interference |
| CN106161011A (en) * | 2016-08-19 | 2016-11-23 | 浙江神州量子网络科技有限公司 | A kind of plug and play quantum key dissemination system based on coding time phase and method and transmitting terminal and receiving terminal |
| CN106533676A (en) * | 2016-12-22 | 2017-03-22 | 浙江神州量子网络科技有限公司 | Quantum key distribution system based on reference system independent protocol |
| CN206790495U (en) * | 2017-05-22 | 2017-12-22 | 中国科学技术大学 | A kind of decoding apparatus for time bit phase coding |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPWO2020189348A1 (en) * | 2019-03-18 | 2020-09-24 | ||
| WO2020189348A1 (en) * | 2019-03-18 | 2020-09-24 | 日本電気株式会社 | Light modulation method and device using nest-type light modulator |
| JP7164013B2 (en) | 2019-03-18 | 2022-11-01 | 日本電気株式会社 | Optical modulation method and apparatus using nested optical modulator |
| US11546065B2 (en) | 2019-03-18 | 2023-01-03 | Nec Corporation | Optical modulation method and device using nested optical modulator |
| CN110752922A (en) * | 2019-10-24 | 2020-02-04 | 四川航天系统工程研究所 | Decoder and time coding quantum key distribution decoding method |
| WO2021199027A1 (en) | 2020-04-02 | 2021-10-07 | Lidwave Ltd. | Method and apparatus for mapping and ranging based on coherent-time comparison |
| CN114613234A (en) * | 2020-12-08 | 2022-06-10 | 科大国盾量子技术股份有限公司 | Quantum communication attack and defense demonstration system based on photon number separation |
| CN114613234B (en) * | 2020-12-08 | 2023-10-03 | 科大国盾量子技术股份有限公司 | Quantum communication attack and defense demonstration system based on photon number separation |
| CN114629629A (en) * | 2020-12-14 | 2022-06-14 | 科大国盾量子技术股份有限公司 | Receiving device, QKD system and quantum communication method |
| CN114629629B (en) * | 2020-12-14 | 2024-04-30 | 科大国盾量子技术股份有限公司 | Receiving device, QKD system and quantum communication method |
| CN113114355A (en) * | 2021-06-15 | 2021-07-13 | 国开启科量子技术(北京)有限公司 | Method and apparatus for detecting quantum communication system |
| CN113114355B (en) * | 2021-06-15 | 2021-08-13 | 国开启科量子技术(北京)有限公司 | Method and apparatus for detecting quantum communication system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108964778A (en) | It is a kind of for time bit-phase code decoding apparatus | |
| CN106161011B (en) | Plug-and-play quantum key distribution system and method based on time-phase coding, sending end and receiving end | |
| CN107612690B (en) | Phase decoding method and device and quantum key distribution system | |
| CN106161009B (en) | Quantum key distribution system based on time-phase encoding | |
| CN106533676B (en) | A kind of quantum key distribution system based on referential independent protocol | |
| RU2671620C1 (en) | High-speed autocompensation scheme of quantum key distribution | |
| CN108650091B (en) | Phase decoding method, phase decoding receiving device and quantum key distribution system | |
| CN109560876B (en) | Time phase-polarization encoding device, decoding device, and quantum communication system | |
| US8477939B2 (en) | Polarization-insensitive one-way quantum key distribution receiver, transmitter/receiver system | |
| US10162245B2 (en) | Distributed acoustic sensing system based on delayed optical hybrid phase demodulator | |
| US20090046857A1 (en) | Quantum cryptography transmission system and optical device | |
| CN104579643A (en) | Two-node measuring equipment unrelated quantum key distribution system | |
| CN206790495U (en) | A kind of decoding apparatus for time bit phase coding | |
| CN210041849U (en) | Polarization-independent phase coding quantum key distribution system | |
| CN110108346A (en) | Optical fibre vibration sensor based on delay phase modulation chirped pulse pair | |
| CN108540283A (en) | A kind of improved HD-QKD systems | |
| CN114629563B (en) | Polarization multiplexing quantum key distribution device and full-time full-pass quantum key distribution network | |
| CN105091919A (en) | High-sensitivity double optical fiber and cable sensor | |
| CN205961140U (en) | Plug -and -play quantum key distribution system and transmitting terminal and receiving terminal based on time phase coding | |
| US20070114751A1 (en) | Optical fiber interferometer with relaxed loop tolerance and QKD system using same | |
| CN109391471B (en) | Hybrid waveguide integrated interferometer and quantum key distribution system | |
| CN217590831U (en) | QKD system based on time phase coding | |
| CN116455566A (en) | Quantum key distribution method and system based on high-dimensional entanglement | |
| CN208797953U (en) | A kind of phase code system of low error rate and its receiving end | |
| CN208424384U (en) | A kind of time bit phase coded system |
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 |