CN116980113A - Method for screening out measurement abnormal value in atmospheric optical channel key extraction - Google Patents

Abstract

The invention discloses a method for screening out a measurement abnormal value in atmospheric optical channel key extraction. According to the method, the differential amplitude of the measured sampling values of the transmission optical signals in the collected atmosphere optical channels is compared, the measured abnormal values in the electric signal data collected by the two communication parties are screened out, the influence of channel noise and equipment noise on channel reciprocity is reduced, and the purpose of improving the consistency rate of the original shared random bit sequences extracted by the two communication parties is achieved.

Description

Method for screening out measurement abnormal value in atmospheric optical channel key extraction

Technical Field

The invention belongs to the technical field of information security, and relates to a method for screening out a measured abnormal value in atmospheric optical channel key extraction.

Background

Nowadays, information security is of interest. In network communication, in order to protect data transmitted by both communication parties, it is generally necessary to encrypt the transmitted data. If the shared key distribution is implemented by using the traditional public key system, the security of the quantum computer is challenged after the quantum computer is put into practical use. Quantum key distribution is also a technique for distributing shared keys to legitimate communicating parties, but current quantum key distribution is too costly to implement. How to distribute shared keys to legitimate communicating parties with low cost and security is a matter of further investigation.

Researchers have proposed a method of extracting shared random bits from random optical signals of reciprocal bidirectional atmospheric turbulence optical channels, and then using the extracted shared random bits to generate a random key shared by both parties communicating across the channel. When extracting random bits from random optical signals, the random optical signals need to be measured and sampled at first, and then thresholding calculation is carried out on sampling values. In an ideal state, the channel reciprocity is good, the measured sampling value does not contain noise, and the random bit sequences extracted from the two ends of the channel are basically the same on the basis; in practice, however, random extreme conditions occur in a bidirectional optical transmission channel established by two sighted laser receiving and transmitting ends in the earth atmosphere environment, so that channel reciprocity is weakened, the measured sampling value is abnormal, and finally, the consistency rate of extracting random bit sequences at two ends of the channel is reduced. The chinese patent application No. 202011376004.1 states that the precondition of ensuring that the random bit sequences extracted from both ends of the channel (referred to as the original shared random bit sequences) are substantially the same is that the bidirectional optical transmission channel has good reciprocity, so that it is necessary to screen out the abnormal value of the random optical signal measurement sampling value after obtaining the random optical signal measurement sampling value during the actual key extraction, and then perform thresholding calculation to obtain the original shared random bit sequence. The consistency rate of extracting the original shared random bit sequence at the two ends of the channel can be obviously improved by measuring the outlier and screening out. The invention discloses a method for screening out measured abnormal values in the extraction of an atmosphere optical channel key.

Disclosure of Invention

The invention aims to provide a method for screening out measured abnormal values in the extraction of an atmosphere optical channel key, which is used for screening out the measured abnormal values by comparing differential amplitude values of sampling values measured at two ends of an atmosphere bidirectional optical channel, and carrying out operations such as quantization, negotiation and the like on the basis of the differential amplitude values, so as to improve the consistency rate of the extraction of shared random bit sequences at two ends of the channel.

The technical scheme of the method is realized as follows: the differential amplitude comparison screening method for the measured outliers in the atmospheric optical channel key extraction is characterized by comprising the following steps of:

the laser transceiver A and the laser transceiver B are needed to be mutually seen. The laser transceiver A comprises a laser A, a transceiver optical system A, a detector A and a computer A. The laser transceiver B comprises a laser B, a transceiver optical system B, a detector B and a computer B. As shown in fig. 1, a laser signal a001 emitted by the laser a is emitted into an atmospheric turbulence channel through the transceiver optical system a, and the laser signal a001 reaches the transceiver optical system B and then is incident on the detector B; the laser signal B001 sent by the laser B is sent to an atmospheric turbulence channel through the receiving and transmitting optical system B, and the laser signal B001 is incident on the detector A after reaching the receiving and transmitting optical system A; the computer A acquires the electric signals output by the detector A in real time, and the computer B acquires the electric signals output by the detector B in real time.

1) The first part of the method is to make the laser transceiver A and the laser transceiver B work normally, and the specific operations include:

step101: the laser A and the laser B are enabled to work normally, the detector A and the detector B are enabled to work normally, the computer A and the computer B are enabled to work normally, and the transceiver optical system A and the transceiver optical system B are enabled to align with each other and work normally.

2) The second part of the method performs the following operations in the laser transceiver a:

step201: creating a in computer ACounter, let counter=1; let time t _A =0; creating a one-dimensional array ArrayA containing N elements in a memory of the computer A, wherein the array ArrayA is used for storing amplitude sampling values of the electric signals output by the detector A; creating a one-dimensional array ArrayA_1 containing N elements in a memory of the computer A, wherein the array ArrayA_1 is used for storing a result obtained by normalizing sampling values in the array ArrayA; creating a unidirectional queue A with the length of m in a memory of the computer A, wherein m is an even number smaller than N, and the unidirectional queue A is used for temporarily storing differential amplitude values of adjacent elements in the array ArrayA_1; creating a one-dimensional array ArrayAA with the length of N in a memory of the computer A, wherein the array ArrayAA is used for storing the sum of elements in the unidirectional queue QueueA at different times; creating a one-dimensional array ArrayA_2 in a memory of the computer A, wherein the array ArrayA_2 is used for storing a result of removing the abnormal value of the element in the array ArrayA_1; creating a list ListA in the memory of computer a, the list ListA being for storing a random bit sequence, leaving the list ListA empty; wherein the unidirectional queue structure is shown in fig. 2;

Step202: at time t _A The acquisition program of the laser transceiver A samples the amplitude of the electric signal output by the detector A once to obtain a sampling value C001; assigning the CounterA element of the array ArrayA as a sampling value C001;

step203: let coutera = coutera+1; let t _A ＝t _A +δ _t ，δ _t Is a sampling time interval;

step204: if CounterA > N, go to Step205, otherwise go to Step202;

step205: in computer a, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order by the program: and (3) carrying out normalization processing on each sampling value in the array A:

step205-1: let I _A [i]Representing the ith sampling value in the array ArrayA; i _{A_1} [i]Representing the result of normalized processing of the ith sampling value in the array ArrayA;

step205-2: order theAssigning the ith element in the array ArryaA_1 as I _{A_1} [i]The method comprises the steps of carrying out a first treatment on the surface of the Wherein i' and i "are both positive integers;

step206: respectively in turn forThe following operations are performed:

step206-1: let I _{A_1} [i]Representing the value of the ith element in array ArrayA_1, let V _A ＝|I _{A_1} [i]-I _{A_1} [i+1]I, wherein |x| represents taking the absolute value of x;

step206-2: will V _A Enqueue into a unidirectional queue a;

step207: respectively in turn for The following operations are performed:

step207-1: let I _{A_1} [i]Representing the value of the ith element in array ArrayA_1, let V _A ＝|I _{A_1} [i]-I _{A_1} [i+1]|；

Step207-2: will V _A Enqueue in a unidirectional queue QueueA, let S _A Equal to the sum of all element values in the current unidirectional queue QueueA, the first element in the array ArrayAA is addedThe individual elements are assigned S _A The method comprises the steps of carrying out a first treatment on the surface of the When the queue A of the unidirectional queue is full, dequeuing the queue head element, then moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation, as shown in figure 3;

step208: respectively in turn forThe following operations are performed:

step208-1: let Q _A The queue head element representing the current unidirectional queue QueueA, will Q _A From sheetDequeuing the queue from the queue A, and moving the other elements by one unit towards the direction of the queue head;

step208-2: let S _A Equal to the sum of all element values in the current unidirectional queue QueueA; array ArrayAA No.The individual elements are assigned S _A ；

Step209: and the laser transceiver A sends the array ArrayAA to the laser transceiver B.

3) The third part of the method performs the following operations in the laser transceiver B:

step301: creating a counter in computer B, letting counter=1; let time t _B =0; creating a one-dimensional array ArrayB containing N elements in a memory of the computer B, wherein the array ArrayB is used for storing amplitude sampling values of the electric signals output by the detector B; creating a one-dimensional array ArrayB_1 containing N elements in a memory of the computer B, wherein the array ArrayB_1 is used for storing a result of normalization processing of sampling values of the array ArrayB; creating a unidirectional queue B with a length of m in a memory of the computer B, wherein m is an even number smaller than N, and the unidirectional queue B is used for temporarily storing differential amplitudes of adjacent elements in the array ArrayB_1; creating a one-dimensional array ArrayBB with the length of N in a memory of the computer B, wherein the array ArrayBB is used for storing the sum of elements in the unidirectional queue QueueA at different times; creating a one-dimensional array ArrayBD with the length of N in a memory of a computer B, wherein the array ArrayBD is used for storing index information marked during the first round of outlier screening; creating a unidirectional queue QueueBD with the length of N in a memory of the computer B, wherein N is an odd number smaller than N, and the unidirectional queue QueueBD is used for temporarily storing data in an array ArrayBD; creating a one-dimensional array ArrayBP with the length of N in a memory of a computer B for storing index information of the marker during the second round of outlier screening; creating a one-dimensional array ArrayB_2 in a memory of the computer B, wherein the array ArrayB_2 is used for storing the result of the elements in the array ArrayB_1 after the abnormal values are screened out; creating a in the memory of computer B A list ListB for storing a random bit sequence, leaving list ListB empty; wherein the unidirectional queue structure is shown in fig. 2;

step302: at time t _B The laser transceiver B samples the amplitude of the electric signal output by the detector B once to obtain a sampling value D001; assigning the CounterB elements of the array ArrayB to a sampling value D001;

step303: let counterb=counterb+1; let t _B ＝t _B +δ _t ，δ _t Is a sampling time interval;

step304: if CounterB > N, go to Step305, otherwise go to Step302;

step305: in computer B, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order by the program: and (3) carrying out normalization processing on each sampling value in the array B:

step305-1: let I _B [i]Representing the ith sampling value in the array ArrayB; i _{B_1} [i]Representing the result of normalized processing of the ith sampling value in the array ArrayB;

step305-2: order theAssigning the ith element in the array ArryaB_1 as I _{B_1} [i]The method comprises the steps of carrying out a first treatment on the surface of the Wherein i 'and i' are both positive integers;

step306: respectively in turn forThe following operations are performed:

step306-1: let I _{B_1} [i]Representing the value of the ith element in array ArrayB_1, let V _B ＝|I _{B_1} [i]-I _{B_1} [i+1]|；

Step306-2: will V _B Enqueue into a unidirectional queue b;

step307: respectively in turn forThe following operations are performed:

step307-1: let I _{B_1} [i]Representing the value of the ith element in array ArrayB_1, let V _B ＝|I _{B_1} [i]-I _{B_1} [i+1]|；

Step307-2: will V _B Enqueue in a unidirectional queue QueueB, let S _B Equal to the sum of all element values in the current unidirectional queue QueueB, the first element in the array ArrayBBThe individual elements are assigned S _B The method comprises the steps of carrying out a first treatment on the surface of the When the queue B is full, dequeuing the queue head element, moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation, as shown in figure 3;

step308: respectively in turn forThe following operations are performed:

step308-1: let Q _B The queue head element representing the current unidirectional queue QueueB, will Q _B Dequeuing from the unidirectional queue QueueB, and moving the other elements by one unit towards the direction of the queue head;

step308-2: let S _B Equal to the sum of all element values in the current unidirectional queue QueueB; the first of the array ArrayBBThe individual elements are assigned S _B 。

4) After the fourth part of the method receives the array ArrayAA sent by the laser transceiver A in Step209 by the laser transceiver B, the computer B of the laser transceiver B determines the index of the measured abnormal value, and the specific operation steps are as follows:

Step401: let T _B For the first round of abnormal screening decision threshold, the following operations are performed for i=1, 2, …, N-1, N in sequence:

step401-1: let I _AA [i]Representing the value of the ith element in the array ArrayAA, let I _BB [i]Representation ofThe value of the ith element in the array ArrayBB;

step401-2: order the

Step401-3: if P _B ≥T _B The i element in the array ArrayBD is assigned to be 1;

step401-4: if P _B ＜T _B Then the i element in the array ArrayBD is assigned to 0;

step402:represents rounding down on x, respectively for ++>The following operations are performed:

step402-1: let I _BD [i]Representing the value of the ith element in the array ArrayBD, will be I _BD [i]Enqueue into a unidirectional queue QueueBD;

step403: let T _BD The decision threshold is screened out for the second round of anomalies,represents rounding up x, respectively for ++>The following operations are performed:

step403-1: let I _BD [i]Representing the value of the ith element in the array ArrayBD, will be I _BD [i]Enqueue in a unidirectional queue QueueBD, let S _BD Equal to the sum of all element values in the current unidirectional queue QueueBD; when the queue of the unidirectional queue QueueBD is full, dequeuing the queue head element, then moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation, as shown in fig. 3;

Step403-2: if it isThen the +.>The value of each element is 1;

step403-3: if it isThen the +.>The value of each element is 0;

step404: in turn forThe following operations are performed:

step404-1: let Q _BD Queue head element representing unidirectional queue QueueBD, will Q _BD Dequeuing from the unidirectional queue QueueBD, and moving the other elements by one unit towards the direction of the queue head to enable S _BD Equal to the sum of all element values in the current unidirectional queue QueueBD;

step404-2: if it isThen the +.>The value of each element is 1;

step404-3: if it isThen the +.>The value of each element is 0;

step405: and the laser transceiver B sends the array ArrayBP to the laser transceiver A.

5) After the fifth part of the method receives the array ArrayBP sent by the laser transceiver B in Step405, the computer A of the laser transceiver A performs outlier screening operation and thresholding calculation on the array ArrayA_1, and the specific steps are as follows:

step501: let j=1, j be a positive integer, and the following operations are performed for i=1, 2, …, N-1, N in order:

step501-1: let I _BP [i]Representing the value of the ith element in the array ArrayBP, let I _{A_1} [i]A value representing the i-th element in array ArrayA_1; let I _{A_2} [j]A value representing the j-th element in the array ArrayA_2;

step501-2: if I _BP [i]=0, let I _{A_2} [j]＝I _{A_1} [i]Let j=j+1;

step501-3: if I _BP [i]=1, then no operation is done;

step502: thresholding each element in the array ArrayA_2 by using a quantization algorithm to obtain a random bit sequence, and storing the random bit sequence into a list ListA;

step503: the laser transceiver A completes the original shared random bit sequence extraction operation.

6) In the sixth part of the method, the abnormal value screening operation and thresholding calculation are carried out on the data ArrayB_1 by the computer B of the laser transceiver B, and the specific steps are as follows:

step601: let j=1, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order:

step601-1: let I _BP [i]Representing the value of the ith element in the array ArrayBP, let I _{B_1} [i]A value representing the i-th element in array ArrayB_1; let I _{B_2} [j]A value representing the j-th element in the array ArrayB_2;

step601-2: if I _BP [i]=0, let I _{B_2} [j]＝I _{B_1} [i]Let j=j+1;

step601-3: if I _BP [i]=1, then no operation is done;

step602: thresholding each element in the array ArrayB_2 by using a quantization algorithm to obtain a random bit sequence, and storing the random bit sequence into a list ListB;

Step603: the laser transceiver B completes the original shared random bit sequence extraction operation.

7) The seventh part of the method corrects inconsistent bits in the original shared random bit sequence extracted by the laser transceiver A and the laser transceiver B, and comprises the following specific steps:

step701: and using error code estimation, key negotiation and error checking technology in the quantum key distribution post-processing to find and correct inconsistent bits in original shared random bit sequences stored in the list LittA and the list LittB, so that the random bits in the list LittA and the list LittB are consistent, and the laser transceiver A and the laser transceiver B have the same bit sequence.

In practicing the method, a first portion of the method is performed, then a second portion and a third portion of the method are performed simultaneously, then a fourth portion is performed, then a fifth portion and a sixth portion are performed simultaneously, and finally a seventh portion of the method is performed.

The invention has the positive effects that: the method of the invention screens out the measured abnormal value in the extraction of the air optical channel key by differential amplitude comparison; the differential amplitude values of the sampling values measured by the two communication parties are calculated respectively by using the method, the differential amplitude values are transmitted, and the differential amplitude values of the sampling values measured by the two ends of the atmospheric bidirectional optical channel are compared, so that the screening of the abnormal measurement values is realized. And after the outlier is screened out, thresholding calculation is carried out on the outlier, so that the consistency rate of the original shared random bit sequence extracted by both sides of the channel can be obviously improved.

Drawings

Fig. 1 is a schematic diagram of a system hardware structure.

Fig. 2 is a schematic diagram of a unidirectional queue structure.

FIG. 3 is a diagram of an example of uni-directional queue enqueue.

Detailed Description

In order to make the features and advantages of the present method more apparent, the present method will be further described in connection with the following specific examples. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. In this embodiment, the laser transceiver a and the laser transceiver B are respectively located on roofs of two high buildings, the detector a and the detector B are PIN photodetectors, the computer a of the laser transceiver a and the computer B of the laser transceiver B are both connected to the internet, and the computer a and the computer B can communicate with each other through the internet to perform error code estimation, key negotiation, and error check operation through an internet channel. The laser A and the laser B both output laser signals with stable power, and the power of the laser signals output by the laser A is equal to that of the laser signals output by the laser B. Papers published on pages 113-121 of volume 2 in the "cryptology report" 2015 are used for describing error code estimation, key negotiation and error check operation in the quantum key distribution post-processing. The error code estimation, key negotiation and error check technology used in the quantum key distribution post-processing can carry out inconsistent bit error correction on the original shared random bit sequences extracted by the two laser transceiver terminals, and the finally obtained shared random bit sequences are determined to be changed into shared random bit sequences which can be used in practice. The transceiving optical system A and the transceiving optical system B ensure that a bidirectional channel between the laser transceiver A and the laser transceiver B is reciprocal in a manner described in the paper of pages 16422-16441 of the volume 13 of the book 26 of Optics Express 2018.

The technical scheme of the method is realized as follows: the differential amplitude comparison screening method for the measured outliers in the atmospheric optical channel key extraction is characterized by comprising the following steps of:

the laser transceiver A and the laser transceiver B are needed to be mutually seen. The laser transceiver A comprises a laser A, a transceiver optical system A, a detector A and a computer A. The laser transceiver B comprises a laser B, a transceiver optical system B, a detector B and a computer B. As shown in fig. 1, a laser signal a001 emitted by the laser a is emitted into an atmospheric turbulence channel through the transceiver optical system a, and the laser signal a001 reaches the transceiver optical system B and then is incident on the detector B; the laser signal B001 sent by the laser B is sent to an atmospheric turbulence channel through the receiving and transmitting optical system B, and the laser signal B001 is incident on the detector A after reaching the receiving and transmitting optical system A; the computer A acquires the electric signals output by the detector A in real time, and the computer B acquires the electric signals output by the detector B in real time.

1) The first part of the method is to make the laser transceiver A and the laser transceiver B work normally, and the specific operations include:

Step101: the laser A and the laser B are enabled to work normally, the detector A and the detector B are enabled to work normally, the computer A and the computer B are enabled to work normally, and the transceiver optical system A and the transceiver optical system B are enabled to align with each other and work normally.

2) The second part of the method performs the following operations in the laser transceiver a:

step201: creating a counter in computer a, wherein counter=1; let time t _A =0; creating a one-dimensional array ArrayA containing N elements in a memory of the computer A, wherein the array ArrayA is used for storing amplitude sampling values of the electric signals output by the detector A; creating a one-dimensional array ArrayA_1 containing N elements in a memory of the computer A, wherein the array ArrayA_1 is used for storing a result obtained by normalizing sampling values in the array ArrayA; creating a unidirectional queue A with the length of m in a memory of the computer A, wherein m is an even number smaller than N, and the unidirectional queue A is used for temporarily storing differential amplitude values of adjacent elements in the array ArrayA_1; creating a one-dimensional array ArrayAA with the length of N in a memory of the computer A, wherein the array ArrayAA is used for storing the sum of elements in the unidirectional queue QueueA at different times; creating a one-dimensional array ArrayA_2 in a memory of the computer A, wherein the array ArrayA_2 is used for storing a result of removing the abnormal value of the element in the array ArrayA_1; creating a list ListA in the memory of computer a, the list ListA being for storing a random bit sequence, leaving the list ListA empty; wherein the unidirectional queue structure is shown in fig. 2;

Step202: at time t _A Acquisition program pair of laser transceiver AThe amplitude of the electric signal output by the detector A is sampled once to obtain a sampling value C001; assigning the CounterA element of the array ArrayA as a sampling value C001;

step203: let coutera = coutera+1; let t _A ＝t _A +δ _t ，δ _t Is a sampling time interval;

step204: if CounterA > N, go to Step205, otherwise go to Step202;

step205: in computer a, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order by the program: and (3) carrying out normalization processing on each sampling value in the array A:

step205-1: let I _A [i]Representing the ith sampling value in the array ArrayA; i _{A_1} [i]Representing the result of normalized processing of the ith sampling value in the array ArrayA;

step205-2: order theAssigning the ith element in the array ArryaA_1 as I _{A_1} [i]The method comprises the steps of carrying out a first treatment on the surface of the Wherein i' and i "are both positive integers;

step206: respectively in turn forThe following operations are performed:

step206-1: let I _{A_1} [i]Representing the value of the ith element in array ArrayA_1, let V _A ＝|I _{A_1} [i]-I _{A_1} [i+1]I, wherein |x| represents taking the absolute value of x;

step206-2: will V _A Enqueue into a unidirectional queue a;

step207: respectively in turn for The following operations are performed:

step207-1: let I _{A_1} [i]Representing the value of the ith element in array ArrayA_1, let V _A ＝|I _{A_1} [i]-I _{A_1} [i+1]|；

Step207-2: will V _A Enqueue in a unidirectional queue QueueA, let S _A Equal to the sum of all element values in the current unidirectional queue QueueA, the first element in the array ArrayAA is addedThe individual elements are assigned S _A The method comprises the steps of carrying out a first treatment on the surface of the When the queue A of the unidirectional queue is full, dequeuing the queue head element, then moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation, as shown in figure 3;

step208: respectively in turn forThe following operations are performed:

step208-1: let Q _A The queue head element representing the current unidirectional queue QueueA, will Q _A Dequeuing from the unidirectional queue QueueA, and moving the other elements by one unit towards the direction of the queue head;

step208-2: let S _A Equal to the sum of all element values in the current unidirectional queue QueueA; array ArrayAA No.The individual elements are assigned S _A ；

Step209: and the laser transceiver A sends the array ArrayAA to the laser transceiver B.

3) The third part of the method performs the following operations in the laser transceiver B:

step301: creating a counter in computer B, letting counter=1; let time t _B =0; creating a one-dimensional array ArrayB containing N elements in a memory of the computer B, wherein the array ArrayB is used for storing amplitude sampling values of the electric signals output by the detector B; creating a one-dimensional array ArrayB_1 containing N elements in a memory of the computer B, wherein the array ArrayB_1 is used for storing a result of normalization processing of sampling values of the array ArrayB; creating a single length m in the memory of computer B The method comprises the steps of (1) temporarily storing differential amplitude values of adjacent elements in an array ArrayB_1 to a queue QueueB, wherein m is an even number smaller than N; creating a one-dimensional array ArrayBB with the length of N in a memory of the computer B, wherein the array ArrayBB is used for storing the sum of elements in the unidirectional queue QueueA at different times; creating a one-dimensional array ArrayBD with the length of N in a memory of a computer B, wherein the array ArrayBD is used for storing index information marked during the first round of outlier screening; creating a unidirectional queue QueueBD with the length of N in a memory of the computer B, wherein N is an odd number smaller than N, and the unidirectional queue QueueBD is used for temporarily storing data in an array ArrayBD; creating a one-dimensional array ArrayBP with the length of N in a memory of a computer B for storing index information of the marker during the second round of outlier screening; creating a one-dimensional array ArrayB_2 in a memory of the computer B, wherein the array ArrayB_2 is used for storing the result of the elements in the array ArrayB_1 after the abnormal values are screened out; creating a list in the memory of the computer B, the list being used for storing the random bit sequence, leaving the list empty; wherein the unidirectional queue structure is shown in fig. 2;

Step302: at time t _B The laser transceiver B samples the amplitude of the electric signal output by the detector B once to obtain a sampling value D001; assigning the CounterB elements of the array ArrayB to a sampling value D001;

step303: let counterb=counterb+1; let t _B ＝t _B +δ _t ，δ _t Is a sampling time interval;

step304: if CounterB > N, go to Step305, otherwise go to Step302;

step305: in computer B, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order by the program: and (3) carrying out normalization processing on each sampling value in the array B:

step305-1: let I _B [i]Representing the ith sampling value in the array ArrayB; i _{B_1} [i]Representing the result of normalized processing of the ith sampling value in the array ArrayB;

step305-2: order theAssigning the ith element in the array ArryaB_1 as I _{B_1} [i]The method comprises the steps of carrying out a first treatment on the surface of the Wherein i' and i "are both positive integers;

step306: respectively in turn forThe following operations are performed:

step306-1: let I _{B_1} [i]Representing the value of the ith element in array ArrayB_1, let V _B ＝|I _{B_1} [i]-I _{B_1} [i+1]|；

Step306-2: will V _B Enqueue into a unidirectional queue b;

step307: respectively in turn forThe following operations are performed:

step307-1: let I _{B_1} [i]Representing the value of the ith element in array ArrayB_1, let V _B ＝|I _{B_1} [i]-I _{B_1} [i+1]|；

Step307-2: will V _B Enqueue in a unidirectional queue QueueB, let S _B Equal to the sum of all element values in the current unidirectional queue QueueB, the first element in the array ArrayBBThe individual elements are assigned S _B The method comprises the steps of carrying out a first treatment on the surface of the When the queue B is full, dequeuing the queue head element, moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation, as shown in figure 3;

step308: respectively in turn forThe following operations are performed:

step308-1: let Q _B The queue head element representing the current unidirectional queue QueueB, will Q _B Dequeuing from unidirectional queue B, the remaining elements being directedThe head of the team moves by one unit;

step308-2: let S _B Equal to the sum of all element values in the current unidirectional queue QueueB; the first of the array ArrayBBThe individual elements are assigned S _B 。

4) After the fourth part of the method receives the array ArrayAA sent by the laser transceiver A in Step209 by the laser transceiver B, the computer B of the laser transceiver B determines the index of the measured abnormal value, and the specific operation steps are as follows:

step401: let T _B For the first round of abnormal screening decision threshold, the following operations are performed for i=1, 2, …, N-1, N in sequence:

step401-1: let I _AA [i]Representing the value of the ith element in the array ArrayAA, let I _BB [i]A value representing the ith element in the array ArrayBB;

step401-2: order the

Step401-3: if P _B ≥T _B The i element in the array ArrayBD is assigned to be 1;

step401-4: if P _B ＜T _B Then the i element in the array ArrayBD is assigned to 0;

step402:represents rounding down on x, respectively for ++>The following operations are performed:

step402-1: let I _BD [i]Representing the value of the ith element in the array ArrayBD, will be I _BD [i]Enqueue into a unidirectional queue QueueBD;

step403: let T _BD For the second wheelThe abnormality screen-out decision threshold value,represents rounding up x, respectively for ++>The following operations are performed:

step403-1: let I _BD [i]Representing the value of the ith element in the array ArrayBD, will be I _BD [i]Enqueue in a unidirectional queue QueueBD, let S _BD Equal to the sum of all element values in the current unidirectional queue QueueBD; when the queue of the unidirectional queue QueueBD is full, dequeuing the queue head element, then moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation, as shown in fig. 3;

step403-2: if it isThen the +.>The value of each element is 1;

step403-3: if it isThen the +.>The value of each element is 0;

Step404: in turn forThe following operations are performed:

step404-1: let Q _BD Queue head element representing unidirectional queue QueueBD, will Q _BD Dequeuing from the unidirectional queue QueueBD, and moving the other elements by one unit towards the direction of the queue head to enable S _BD Equal to the sum of all element values in the current unidirectional queue QueueBD;

step404-2: if it isThen the +.>The value of each element is 1;

step404-3: if it isThen the +.>The value of each element is 0;

step405: and the laser transceiver B sends the array ArrayBP to the laser transceiver A.

5) After the fifth part of the method receives the array ArrayBP sent by the laser transceiver B in Step405, the computer A of the laser transceiver A performs outlier screening operation and thresholding calculation on the array ArrayA_1, and the specific steps are as follows:

step501: let j=1, j be a positive integer, and the following operations are performed for i=1, 2, …, N-1, N in order:

step501-1: let I _BP [i]Representing the value of the ith element in the array ArrayBP, let I _{A_1} [i]A value representing the i-th element in array ArrayA_1; let I _{A_2} [j]A value representing the j-th element in the array ArrayA_2;

step501-2: if I _BP [i]=0, let I _{A_2} [j]＝I _{A_1} [i]Let j=j+1;

step501-3: if I _BP [i]=1, then no operation is done;

step502: thresholding each element in the array ArrayA_2 by using a quantization algorithm to obtain a random bit sequence, and storing the random bit sequence into a list ListA;

step503: the laser transceiver A completes the original shared random bit sequence extraction operation.

6) In the sixth part of the method, the abnormal value screening operation and thresholding calculation are carried out on the data ArrayB_1 by the computer B of the laser transceiver B, and the specific steps are as follows:

step601: let j=1, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order:

step601-1: let I _BP [i]Representing the value of the ith element in the array ArrayBP, let I _{B_1} [i]A value representing the i-th element in array ArrayB_1; let I _{B_2} [j]A value representing the j-th element in the array ArrayB_2;

step601-2: if I _BP [i]=0, let I _{B_2} [j]＝I _{B_1} [i]Let j=j+1;

step601-3: if I _BP [i]=1, then no operation is done;

step602: thresholding each element in the array ArrayB_2 by using a quantization algorithm to obtain a random bit sequence, and storing the random bit sequence into a list ListB;

step603: the laser transceiver B completes the original shared random bit sequence extraction operation.

7) The seventh part of the method corrects inconsistent bits in the original shared random bit sequence extracted by the laser transceiver A and the laser transceiver B, and comprises the following specific steps:

step701: and using error code estimation, key negotiation and error checking technology in the quantum key distribution post-processing to find and correct inconsistent bits in original shared random bit sequences stored in the list LittA and the list LittB, so that the random bits in the list LittA and the list LittB are consistent, and the laser transceiver A and the laser transceiver B have the same bit sequence.

In practicing the method, a first portion of the method is performed, then a second portion and a third portion of the method are performed simultaneously, then a fourth portion is performed, then a fifth portion and a sixth portion are performed simultaneously, and finally a seventh portion of the method is performed.

In the present embodiment, n=20000; delta _t =0.2 milliseconds; m=4; n=5; t (T) _B ＝0.9；T _BD =0.5; the laser a and laser B output intensities are stable in time. The light intensity output by the laser A and the light intensity output by the laser B are the same.

It will be appreciated by those skilled in the art that arrays and lists are concepts in computer programming, which are collections of elements arranged in a front-to-back order, and are containers for storing data. A queue is a first-in, first-out linear table that allows insertion only at one end of the table and deletion of elements at the other end. With respect to the list, there is a detailed description of 2.1 in chapter 2 of the data structure (C language edition) authored by Yan Weimin, wu Weimin, published by Qinghai university Press under ISBN number 978-7-302-14751-0; regarding the array, details are described in chapter 5.1 and 5.2 of the fifth of the data structures (C language version) written by Yan Weimin, wu Weimin, published by Qinghai university Press under ISBN number 978-7-302-14751-0; in this embodiment, the elements of the array and the list are numbered from 1, and for an array or list including N elements, the element that is first stored is referred to as the 1 st element, and the element that is last stored is referred to as the nth element; the array ArrayBD and the array ArrayBP are used as the arrays for marking and measuring the abnormal value index information, and if the element value in the array ArrayBD and the array ArrayBP is 1, the element which is the same as the element index in the array ArrayA_1 and the array ArrayB_1 is an abnormal value; the differential amplitude is the absolute value of the difference between two adjacent element values, and the calculation process is shown as Step206-1 and Step 306-1; regarding the definition and operation problems of the unidirectional queues, 3.4 of the third chapter in the "data structure (C language edition)" written by Yan Weimin, wu Weimin, published by the university of Qinghai Press having ISBN number 978-7-302-14751-0, is described in detail; the unidirectional queue structure is shown in fig. 2; an example of a one-way queue enqueuing process is shown in fig. 3. The array transfer is involved in Step209 and Step405, and may be performed using laser communication or network communication. In Step502 and Step602, quantization algorithms are used, and in the present application, quantization algorithms of Step502 and Step602 are used The method refers to thresholding the values of each element of the array_2 and array_2 to obtain a 0, 1 bit sequence, for example, thresholding is performed by using a CQA quantization algorithm in the paper of pages 205-215 of volume 10, IEEE Transactions on Mobile Computing in this embodiment to obtain a 0, 1 bit sequence, or thresholding may be performed by using a corresponding quantization algorithm in other papers. FIG. 3 is a diagram of an example of one-way queue enqueuing and dequeuing, which is schematically depicted in FIG. 3, in which the one-way queue has a length of 4, D _A1 、D _A2 …, etc. represent elements that perform enqueuing and dequeuing operations, in this example, when the number of elements in the queue reaches 4, and re-enqueuing is still required, the first element of the queue needs to be dequeued, and the other elements are moved by one unit towards the direction of the queue head, and then the enqueuing operation of the next element is performed. According to the method, indexes of elements to be deleted are finally obtained through two rounds of abnormality screening judgment, the abnormal elements are deleted one by one, and operations such as quantization, information negotiation and the like are performed on the rest elements in the sequence on the basis of the indexes.

Claims (1)

1. The differential amplitude comparison screening method for the measured outliers in the atmospheric optical channel key extraction is characterized by comprising the following steps of:

The technical scheme of the method is realized as follows: the differential amplitude comparison screening method for the measured outliers in the atmospheric optical channel key extraction is characterized by comprising the following steps of:

the laser transceiver A and the laser transceiver B are needed to be mutually viewed; the laser transceiver A comprises a laser A, a transceiver optical system A, a detector A and a computer A; the laser transceiver B comprises a laser B, a transceiver optical system B, a detector B and a computer B; the laser signal A001 sent by the laser A is sent to an atmospheric turbulence channel through the receiving and transmitting optical system A, and the laser signal A001 is incident on the detector B after reaching the receiving and transmitting optical system B; the laser signal B001 sent by the laser B is sent to an atmospheric turbulence channel through the receiving and transmitting optical system B, and the laser signal B001 is incident on the detector A after reaching the receiving and transmitting optical system A; the computer A acquires the electric signals output by the detector A in real time, and the computer B acquires the electric signals output by the detector B in real time;

1) The first part of the method is to make the laser transceiver A and the laser transceiver B work normally, and the specific operations include:

Step101: the laser A and the laser B are enabled to work normally, the detector A and the detector B are enabled to work normally, the computer A and the computer B are enabled to work normally, and the transceiver optical system A and the transceiver optical system B are enabled to align with each other and work normally;

2) The second part of the method performs the following operations in the laser transceiver a:

step201: creating a counter in computer a, wherein counter=1; let time t _A =0; creating a one-dimensional array ArrayA containing N elements in a memory of the computer A, wherein the array ArrayA is used for storing amplitude sampling values of the electric signals output by the detector A; creating a one-dimensional array ArrayA_1 containing N elements in a memory of the computer A, wherein the array ArrayA_1 is used for storing a result obtained by normalizing sampling values in the array ArrayA; creating a unidirectional queue A with the length of m in a memory of the computer A, wherein m is an even number smaller than N, and the unidirectional queue A is used for temporarily storing differential amplitude values of adjacent elements in the array ArrayA_1; creating a one-dimensional array ArrayAA with the length of N in a memory of the computer A, wherein the array ArrayAA is used for storing the sum of elements in the unidirectional queue QueueA at different times; creating a one-dimensional array ArrayA_2 in a memory of the computer A, wherein the array ArrayA_2 is used for storing a result of removing the abnormal value of the element in the array ArrayA_1; creating a list ListA in the memory of computer a, the list ListA being for storing a random bit sequence, leaving the list ListA empty;

Step202: at time t _A The acquisition program of the laser transceiver A samples the amplitude of the electric signal output by the detector A once to obtain a sampling value C001; assigning the CounterA element of the array ArrayA as a sampling value C001;

step Step203 and 203: let coutera = coutera+1; let t _A ＝t _A +δ _t ，δ _t Is a sampling time interval;

step204: if CounterA > N, go to Step205, otherwise go to Step202;

step205: in computer a, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order by the program: and (3) carrying out normalization processing on each sampling value in the array A:

step205-1: let I _A [i]Representing the ith sampling value in the array ArrayA; i _{A_1} [i]Representing the result of normalized processing of the ith sampling value in the array ArrayA;

step205-2: order theAssigning the ith element in the array ArryaA_1 as I _{A_1} [i]The method comprises the steps of carrying out a first treatment on the surface of the Wherein i' and i "are both positive integers;

step206: respectively in turn forThe following operations are performed:

step206-1: let I _{A_1} [i]Representing the value of the ith element in array ArrayA_1, let V _A ＝|I _{A_1} [i]-I _{A_1} [i+1]I, wherein |x| represents taking the absolute value of x;

step206-2: will V _A Enqueue into a unidirectional queue a;

step207: respectively in turn for The following operations are performed:

step207-1: let I _{A_1} [i]Representing the value of the ith element in array ArrayA_1, let V _A ＝|I _{A_1} [i]-I _{A_1} [i+1]|；

Step207-2: will V _A Enqueue in a unidirectional queue QueueA, let S _A Equal to that in the current unidirectional queue aWith sum of element values, the first in array ArrayAAThe individual elements are assigned S _A The method comprises the steps of carrying out a first treatment on the surface of the When the queue A of the unidirectional queue is full, dequeuing the queue head element, moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation;

step208: respectively in turn forThe following operations are performed:

step208-1: let Q _A The queue head element representing the current unidirectional queue QueueA, will Q _A Dequeuing from the unidirectional queue QueueA, and moving the other elements by one unit towards the direction of the queue head;

step208-2: let S _A Equal to the sum of all element values in the current unidirectional queue QueueA; array ArrayAA No.The individual elements are assigned S _A ；

Step209: the laser transceiver A sends the array ArrayAA to the laser transceiver B;

3) The third part of the method performs the following operations in the laser transceiver B:

step301: creating a counter in computer B, letting counter=1; let time t _B =0; creating a one-dimensional array ArrayB containing N elements in a memory of the computer B, wherein the array ArrayB is used for storing amplitude sampling values of the electric signals output by the detector B; creating a one-dimensional array ArrayB_1 containing N elements in a memory of the computer B, wherein the array ArrayB_1 is used for storing a result of normalization processing of sampling values of the array ArrayB; creating a unidirectional queue B with a length of m in a memory of the computer B, wherein m is an even number smaller than N, and the unidirectional queue B is used for temporarily storing differential amplitudes of adjacent elements in the array ArrayB_1; creation in memory of computer B A one-dimensional array ArrayBB with the length of N, wherein the array ArrayBB is used for storing the sum of elements in the unidirectional queue QueueA at different moments; creating a one-dimensional array ArrayBD with the length of N in a memory of a computer B, wherein the array ArrayBD is used for storing index information marked during the first round of outlier screening; creating a unidirectional queue QueueBD with the length of N in a memory of the computer B, wherein N is an odd number smaller than N, and the unidirectional queue QueueBD is used for temporarily storing data in an array ArrayBD; creating a one-dimensional array ArrayBP with the length of N in a memory of a computer B for storing index information of the marker during the second round of outlier screening; creating a one-dimensional array ArrayB_2 in a memory of the computer B, wherein the array ArrayB_2 is used for storing the result of the elements in the array ArrayB_1 after the abnormal values are screened out; creating a list in the memory of the computer B, the list being used for storing the random bit sequence, leaving the list empty;

step302: at time t _B The laser transceiver B samples the amplitude of the electric signal output by the detector B once to obtain a sampling value D001; assigning the CounterB elements of the array ArrayB to a sampling value D001;

Step303: let counterb=counterb+1; let t _B ＝t _B +δ _t ，δ _t Is a sampling time interval;

step304: if CounterB > N, go to Step305, otherwise go to Step302;

step305: in computer B, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order by the program: and (3) carrying out normalization processing on each sampling value in the array B:

step305-1: let I _B [i]Representing the ith sampling value in the array ArrayB; i _{B_1} [i]Representing the result of normalized processing of the ith sampling value in the array ArrayB;

step305-2: order theAssigning the ith element in the array ArryaB_1 as I _{B_1} [i]The method comprises the steps of carrying out a first treatment on the surface of the Wherein i 'and i' are both positive integers；

Step306: respectively in turn forThe following operations are performed:

step306-1: let I _{B_1} [i]Representing the value of the ith element in array ArrayB_1, let V _B ＝|I _{B_1} [i]-I _{B_1} [i+1]|；

Step306-2: will V _B Enqueue into a unidirectional queue b;

step307: respectively in turn forThe following operations are performed:

step307-1: let I _{B_1} [i]Representing the value of the ith element in array ArrayB_1, let V _B ＝|I _{B_1} [i]-I _{B_1} [i+1]|；

Step307-2: will V _B Enqueue in a unidirectional queue QueueB, let S _B Equal to the sum of all element values in the current unidirectional queue QueueB, the first element in the array ArrayBBThe individual elements are assigned S _B The method comprises the steps of carrying out a first treatment on the surface of the When the queue B is full, dequeuing the queue head element, moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation;

step308: respectively in turn forThe following operations are performed:

step308-1: let Q _B The queue head element representing the current unidirectional queue QueueB, will Q _B Dequeuing from the unidirectional queue QueueB, and moving the other elements by one unit towards the direction of the queue head;

step308-2: let S _B Equal to the sum of all element values in the current unidirectional queue QueueB; putting the array ArrayBB intoFirst, theThe individual elements are assigned S _B ；

4) After the fourth part of the method receives the array ArrayAA sent by the laser transceiver A in Step209 by the laser transceiver B, the computer B of the laser transceiver B determines the index of the measured abnormal value, and the specific operation steps are as follows:

step401: let T _B For the first round of abnormal screening decision threshold, the following operations are performed for i=1, 2, …, N-1, N in sequence:

step401-1: let I _AA [i]Representing the value of the ith element in the array ArrayAA, let I _BB [i]A value representing the ith element in the array ArrayBB;

step401-2: order the

Step401-3: if P _B ≥T _B The i element in the array ArrayBD is assigned to be 1;

Step401-4: if P _B ＜T _B Then the i element in the array ArrayBD is assigned to 0;

step402:represents rounding down on x, respectively for ++>The following operations are performed:

step402-1: let I _BD [i]Representing the value of the ith element in the array ArrayBD, will be I _BD [i]Enqueue into a unidirectional queue QueueBD;

step403: let T _BD The decision threshold is screened out for the second round of anomalies,the representation is rounded up to x, respectively forN does the following operations:

step403-1: let I _BD [i]Representing the value of the ith element in the array ArrayBD, will be I _BD [i]Enqueue in a unidirectional queue QueueBD, let S _BD Equal to the sum of all element values in the current unidirectional queue QueueBD; when the one-way queue QueueBD is full, dequeuing the queue head element, moving the other elements to the direction of the queue head by one unit, and finally performing enqueuing operation;

step403-2: if it isThen the +.>The value of each element is 1;

step403-3: if it isThen the +.>The value of each element is 0;

step404: in turn forThe following operations are performed:

step404-1: let Q _BD Queue head element representing unidirectional queue QueueBD, will Q _BD Dequeuing from the unidirectional queue QueueBD, and moving the other elements by one unit towards the direction of the queue head to enable S _BD Equal to the sum of all element values in the current unidirectional queue QueueBD;

step404-2: if it isThen the +.>The value of each element is 1;

step404-3: if it isThen the +.>The value of each element is 0;

step405: the laser transceiver B sends the array ArrayBP to the laser transceiver A;

5) After the fifth part of the method receives the array ArrayBP sent by the laser transceiver B in Step405, the computer A of the laser transceiver A performs outlier screening operation and thresholding calculation on the array ArrayA_1, and the specific steps are as follows:

step501: let j=1, j be a positive integer, and the following operations are performed for i=1, 2, …, N-1, N in order:

step501-1: let I _BP [i]Representing the value of the ith element in the array ArrayBP, let I _{A_1} [i]A value representing the i-th element in array ArrayA_1; let I _{A_2} [j]A value representing the j-th element in the array ArrayA_2;

step501-2: if I _BP [i]=0, let I _{A_2} [j]＝I _{A_1} [i]Let j=j+1;

step501-3: if I _BP [i]=1, then no operation is done;

step502: thresholding each element in the array ArrayA_2 by using a quantization algorithm to obtain a random bit sequence, and storing the random bit sequence into a list ListA;

Step503: the laser transceiver A completes the original shared random bit sequence extraction operation;

6) In the sixth part of the method, the abnormal value screening operation and thresholding calculation are carried out on the data ArrayB_1 by the computer B of the laser transceiver B, and the specific steps are as follows:

step601: let j=1, the following operations are performed for i=1, 2, …, N-1, N, respectively, in order:

step601-1: let I _BP [i]Representing the value of the ith element in the array ArrayBP, let I _{B_1} [i]A value representing the i-th element in array ArrayB_1; let I _{B_2} [j]A value representing the j-th element in the array ArrayB_2;

step601-2: if I _BP [i]=0, let I _{B_2} [j]＝I _{B_1} [i]Let j=j+1;

step601-3: if I _BP [i]=1, then no operation is done;

step602: thresholding each element in the array ArrayB_2 by using a quantization algorithm to obtain a random bit sequence, and storing the random bit sequence into a list ListB;

step603: the laser transceiver B completes the original shared random bit sequence extraction operation;

7) The seventh part of the method corrects inconsistent bits in the original shared random bit sequence extracted by the laser transceiver A and the laser transceiver B, and comprises the following specific steps:

step701: using error code estimation, key negotiation and error checking technology in the quantum key distribution post-processing to find and correct inconsistent bits in original shared random bit sequences stored in a list LittA and a list LittB, so that the random bits in the list LittA and the list LittB are consistent, and the laser transceiver A and the laser transceiver B have the same bit sequence;

In practicing the method, a first portion of the method is performed, then a second portion and a third portion of the method are performed simultaneously, then a fourth portion is performed, then a fifth portion and a sixth portion are performed simultaneously, and finally a seventh portion of the method is performed.