KR101992959B1 - Method and apparatus for estimating binary bit key for information reconciliation of continuous variable quantum key distribution - Google Patents

Abstract

The information receiving unit receives the transmission signal generated based on the transmission side binary bit key from the transmitting end, the error calculating unit generates at least one of the transmission signal, the pre-stored reception side binary bit key, and the predetermined parity check matrix Calculating a binary bit error indicating a difference between a transmitting-side binary bit key and a receiving-side binary bit key based on the received binary bit key and the receiving-side binary bit error; To a binary bit key estimation method for information coordination of continuous variable quantum key distribution and an apparatus therefor.

Description

METHOD AND APPARATUS FOR ESTIMATING BINARY BIT KEY FOR INFORMATION RECONCILIATION OF CONTINUOUS VARIABLE QUANTUM KEY DISTRIBUTION FIELD OF THE INVENTION [0001]

The present invention relates to a binary bit key estimation method and apparatus for information reconciliation, which is a post-processing process of a continuous variable quantum key distribution.

The quantum communication is a communication method using the overlapping property of the two, and the existing communication method is a method of transmitting and receiving information by using difference of wavelength or amplitude mainly by using electromagnetic wave. On the other hand, quantum communication is a method of quantum communication, And a communication method of transmitting and receiving information by using a phenomenon or the like.

For this kind of quantum communication, the transmitting end (Alice) and the receiving end (Bob) distribute a cryptographic key to each other via a quantum channel, and a cryptographic key distributed to a transmitting end (Alice) The cryptographic key distributed to the receiving node Bob may be referred to as a receiving node side quantum key, and this process is referred to as quantum key distribution (QKD).

In this case, if both the transmitting-side quantum key and the receiving-end-side quantum key are continuous variables, the above process is called a continuous variable quantum key distribution (CV-QKD).

Here, in the Continuous Variable Quantum Key Distribution (CV-QKD), each of the transmitting end and the receiving end generates a binary bit key by quantizing its own quantum key to the same rule, The bit key may be referred to as a transmitting end side binary bit key, and the binary bit key held by the receiving end may be referred to as a receiving end side binary bit key.

At this time, due to the characteristics of the quantum channel and the randomness of the generation of the binary bit key, the transmission side binary bit key and the reception side binary bit key are different from each other. As a result, the transmission side binary bit key and the reception side binary bit key The same process is required, which is called the Information Reconciliation process.

In the past, a sliced reconciliation method has been utilized for information reconciliation, which is a post-process of continuous variable quantum key distribution (CV-QKD).

The Sliced Reconciliation method is a method in which a transmission side binary bit key and a reception side side binary bit key are arranged in parallel and then the bits of a binary bit key that the eavesdropper is likely to know are encoded, , And in this process, the eavesdropper discards bits that are likely to be found and shares the remaining key.

However, such a sliced reconciliation method has a very high complexity and requires a large amount of memory because it needs to store a floating value.

Korean Patent Laid-Open Publication No. 10-2015-0031245 (March 23, 2015).

An object of the present invention is to solve the above problems, and it is an object of the present invention to provide a method and apparatus for receiving a transmission signal generated based on a transmitting-end binary bit key from a transmitting terminal, And a transmitting side binary bit key based on the receiving side side binary bit key and the binary bit error based on at least one of the transmission side binary bit key and the reception side binary bit key, .

The problems to be solved by the present invention are not limited to the above-mentioned problem (s), and another problem (s) not mentioned can be clearly understood by those skilled in the art from the following description.

According to another aspect of the present invention, there is provided a method of estimating a binary bit key for information adjustment of a continuous variable quantum key distribution, the method comprising: receiving a transmission signal generated based on a transmission side binary bit key, , The error calculation unit (12), the error calculation unit, and the reception side binary bit key, based on at least one of a transmission signal, a pre-stored reception side binary bit key and a predetermined parity check matrix Calculating a binary bit error and estimating the transmission side binary bit key based on the binary bit key estimator, the receiving side binary bit key and the binary bit error.

For example, the transmission signal is a signal generated by performing an XOR operation on a transmitter-side binary bit key and a pre-selected codeword.

According to one embodiment, the step of calculating a binary bit error includes the steps of XORing a transmission signal and a pre-stored receiving-side binary bit key to generate a first calculation value, and adding a first calculation value to a predetermined parity- And generating a second calculated value, and determining a binary bit error corresponding to the second calculated value based on a pre-stored lookup table.

For example, the step of estimating the transmission-side binary bit key includes a step of XORing the reception-side binary bit key and the binary bit error to estimate the transmission-side binary bit key.

In order to achieve the above object, an apparatus for estimating a binary bit key for information adjustment of a continuous variable quantum key distribution according to an exemplary embodiment of the present invention includes an information receiver for receiving a transmission signal generated based on a transmitter- A binary bit error indicating a difference between the transmitting-side binary bit key and the receiving-end binary bit key based on at least one of a transmitting signal, a pre-stored receiving-side binary bit key, and a predetermined parity check matrix And a binary bit key estimator for estimating a transmitter-side binary bit key based on the error calculator and the receiver-side binary bit key and the binary bit error.

For example, the transmission signal is a signal generated by performing an XOR operation on a transmitter-side binary bit key and a pre-selected codeword.

For example, the error calculation unit may generate a first calculation value by XORing a transmission signal and a pre-stored reception-side binary bit key, and perform a matrix multiplication of the first calculation value with a predetermined parity check matrix to generate a second calculation value , And determines a binary bit error corresponding to the second calculated value based on a lookup table stored in advance.

According to one embodiment, the binary bit key estimator XORs the receiving end side binary bit key and the binary bit error to estimate the transmitting side binary bit key.

According to an embodiment of the present invention, a transmission signal generated based on a transmitting-end binary bit key is received from a transmitting end and at least one of a transmission signal, a pre-stored receiving-end-side binary bit key and a preset parity check matrix A binary bit error indicating a difference between the transmitting-side binary bit key and the receiving-side binary bit key is calculated based on the received binary bit key and the receiving-side binary bit key, It is possible to simplify the error correction through the information reconciliation process.

FIG. 1 is a view for explaining a relation between a transmitter (Alice) and a receiver (Bob) to which a binary bit key estimating apparatus for information adjustment of a continuous variable quantum key distribution is applied, according to an embodiment of the present invention.
2 is a block diagram illustrating a binary bit key estimating apparatus for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention.
3 is a flowchart illustrating a method of estimating a binary bit key for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention.
4 is a flowchart for explaining a step of calculating a binary bit error in a binary bit key estimation method for information adjustment of a continuous variable quantum key distribution, according to an embodiment of the present invention.
5 is a view for explaining a method and apparatus for binary bit key estimation for information adjustment of continuous variable quantum key distribution according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to facilitate a person skilled in the art to easily carry out the technical idea of the present invention. . In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Hereinafter, a binary bit key estimation method and apparatus for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, a receiving terminal 20, Bob and a transmitting terminal 10, to which a binary bit key estimating apparatus 200 for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention is applied will be described with reference to FIGS. 1 and 5, Alice).

FIG. 1 is a view for explaining a relation between a transmitter (Alice) and a receiver (Bob) to which a binary bit key estimating apparatus for information adjustment of a continuous variable quantum key distribution is applied, according to an embodiment of the present invention.

5 is a view for explaining a method and apparatus for binary bit key estimation for information adjustment of continuous variable quantum key distribution according to an embodiment of the present invention.

1, a continuous variable quantum key distribution (CV-QKD) includes a transmitting terminal 10, Alice for transmitting information and a receiving terminal 20, Bob for receiving information. These transmitting terminals 10, Alice And the receiving end 20, Bob distribute cryptographic keys shared for quantum communication via a continuous variable quantum key distribution (CV-QKD).

The apparatus for estimating a binary bit key for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention may be implemented by any one of the transmitter 10 (Alice) or the receiver 20 (Bob) And estimates the binary bit key of the other party.

That is, when the binary bit key estimating apparatus 200 for information adjustment of the continuous variable quantum key distribution according to the embodiment of the present invention is included in the transmitter 10 (Alice), binary The bit-key estimating apparatus 200 can estimate the receiving-side binary bit key, which is the binary bit key held by the receiving terminal 20, Bob.

In contrast, when the binary bit key estimating apparatus 200 for information adjustment of the continuous variable quantum key distribution according to the embodiment of the present invention is included in the receiver 20 (Bob), a binary The bit-key estimating apparatus 200 can estimate the transmitter-side binary bit key, which is a binary bit key held by the transmitter 10 (Alice).

Accordingly, the transmitter 10 and the receiver 20 and the receiver 20 can share the binary key, which is the same encryption key, and can perform quantum communication through the shared binary bit key.

Continuing with FIG. 5, a continuous variable quantum key distribution (CV-QKD) and a binary key key distribution method, which is a step before a binary bit key estimation method and apparatus for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention, The bit key generation method will be briefly described.

5, the transmitter 10 and the receiver 20 and Bob receive an initial quantization key (Raw Key, X) composed of consecutive variables through a known continuous variable quantum key distribution protocol Share.

At this time, the continuous variable quantum key distribution protocol is performed through a quantum channel. In the process of distributing the initial quantum key X through the quantum channel, a continuous variable error (Quantum Error, E) occurs, When the quantum key distribution (CV-QKD) is performed, the transmitting end side initial quantum key X, which is the initial quantum key held by the transmitting end 10, Alice, and the receiving end side initial quantum key, which is the initial quantum key held by the receiving end 20, X ') are different from each other.

Since the transmitting end side initial quantum key X and the receiving end side initial quantum key X 'are each constituted by a continuous variable, it is difficult to be utilized as an encryption key for quantum communication, and the transmitting end 10, Alice and the receiving end 20 , And Bob respectively quantize their initial quantum keys (X, X ') in the same rule to generate a binary bit key that can be used as an encryption key for quantum communication.

At this time, there is a hard decision method as an embodiment of a method in which the transmitting terminal (10, Alice) and the receiving terminal (20, Bob) utilize to generate the binary bit key.

The binary bit key held by the transmitting terminal 10 and Alice is defined as the transmitting terminal side binary bit key X _A and the binary bit key held by the receiving terminal 20 and Bob is defined as the receiving terminal side binary bit X _B , .

Here, for the quantum communication, the binary bit keys held by the transmitting terminal 10, Alice and the receiving terminal 20, Bob must be the same, but only the continuous variable quantum key distribution (CV-QKD) , The transmission side binary bit key (x _A ) and the reception side binary bit key (x _B ) differ from each other due to the characteristics of the quantum channel and the randomness of binary key determination.

In this case, the relationship between the transmitting-side binary bit key (x _A ) and the receiving-side binary bit key (x _B ) can be expressed by the following equation (1).

[Equation 1]

In this case, x _B denotes a receiving side binary bit key, x _A denotes a transmitting side binary bit key, and e 'denotes a binary bit error.

The process of correcting the transmission side binary bit key (x _A ) and the reception side binary bit key (x _B ) to each other is referred to as information reconciliation, and a typical conventional information adjustment method is a slice deconvolution There is a way.

For example, a binary bit key estimation method and apparatus for information coordination of continuous variable quantum key distribution according to an embodiment of the present invention includes a transmitter side binary bit key (X _A ) and a receiver side binary key May mean a method and apparatus for adjusting the bit key X _B to be equal to each other.

At this time, a more detailed description of the continuous variable quantum key distribution (CV-QKD) and the method of generating a binary bit key is well known in the art, and thus a detailed description thereof will be omitted.

Referring now to FIG. 2, a binary bit key estimation apparatus 200 for information coordination of continuous variable quantum key distribution according to an embodiment of the present invention will be described.

2 is a block diagram illustrating a binary bit key estimating apparatus for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention.

2, a binary bit key estimating apparatus 200 for information adjustment of continuous variable quantum key distribution according to an embodiment of the present invention includes an information receiving unit 210, an error calculating unit 220, And an estimation unit 230.

The information receiving unit 210 receives the transmission signal S generated based on the transmitting terminal side binary bit key x _A from the transmitting terminal 10 (Alice).

At this time, the transmitter-side binary bit key (x _A ) may mean a cryptographic key generated by quantizing the transmitter initial-quantum key X as described above.

At this time, the transmission signal S is generated by the transmitter 10 (Alice) for information coordination, and is transmitted to the receiving terminal 10 including the binary bit key estimating apparatus 200 for information adjustment of the continuous variable quantum key distribution according to the embodiment of the present invention (20, Bob).

The error calculator 220 calculates the error value of the transmission side binary bit key (x) based on at least one of the transmission signal S, the preliminarily stored reception side binary bit key x _B , and a predetermined parity check matrix c ^T a binary bit error e 'indicating the difference between the x _A and the receiving-side binary bit key x _B is calculated.

At this time, the receiving-side binary bit key x _B may mean a cryptographic key generated by quantizing the initial quantum key X 'on the receiving end side, as described above.

In this case, the parity check matrix (c ^T ) is a matrix representing a parity check of a linear code, and each row is a matrix expressed by a coefficient of an equation indicating parity check. The parity check matrix A more detailed description of the present invention will be omitted because it is well known in the art.

The binary bit key estimator 230 estimates the transmitter side binary bit key x _A based on the receiving-side binary bit key x _B and the binary bit error e '.

At this time, the transmission signal S is a signal generated by performing an XOR operation on the transmitter-side binary bit key (x _A ) and a pre-selected arbitrary codeword (codeword, v).

At this time, the pre-selected arbitrary codeword v may mean an arbitrarily selected codeword among a plurality of codewords which perform a multiplication operation with the above parity check matrix (c ^T ) to make 0.

For example, a pre-selected codeword v may mean one codeword selected arbitrarily from a plurality of codewords defined by a linear block code.

In other words, a pre-selected codeword v may mean an arbitrarily selected codeword among a plurality of codewords satisfying vc ^T = 0.

For example, the error calculating section 220, the the transmission signal (S) and the pre-stored receiver side binary bit key (x _B) by performing an XOR operation to produce a first calculated value, a predetermined parity check matrix, (c ^T) 1 operation value to generate a second operation value, and determines a binary bit error (e ') corresponding to the second operation value based on a pre-stored lookup table.

For example, the binary bit key estimator 230 performs an XOR operation on the receiving-side binary bit key x _B and the binary bit error e 'to estimate the transmitting-side binary bit key x _A.

A more detailed description of the binary bit key estimator 200 for information coordination of continuous variable quantum key distribution according to an embodiment of the present invention will be described below with reference to FIGS. 3 to 5, do.

Now, referring to FIG. 3, a method of estimating a binary bit key for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention will be described.

3 is a flowchart illustrating a method of estimating a binary bit key for information adjustment of a continuous variable quantum key distribution according to an embodiment of the present invention.

As shown in FIG. 3, a binary bit key estimation method for information adjustment of continuous variable quantum key distribution according to an embodiment of the present invention includes receiving a transmission signal from a transmitting end (S310), calculating a binary bit error A step S320 and a step S330 of estimating a transmitter-side binary bit key.

Step S310 means a step in which the information receiving unit 210 receives the transmission signal S generated based on the transmitting terminal side binary bit key x _A from the transmitting terminal 10 (Alice).

For example, the transmission signal S may be a signal generated by XORing a transmitter-side binary bit key (x _A ) and a pre-selected arbitrary codeword (Codeword, v).

As described above, the pre-selected arbitrary codeword v may mean an arbitrarily selected codeword among a plurality of codewords that perform a multiplication operation with the parity check matrix (c ^T ) described above to make 0 .

For example, in step S310, the information receiving unit 210 may receive the above-described transmission signal S through a classical channel.

For example, before the step S310, each of the transmitting terminal 10, Alice and the receiving terminal 20, Bob combines a plurality of predetermined binary bit keys (x _A , x _B ) to match the length of a predetermined linear code However, the present invention is not limited thereto.

At this time, in step S310, the transmission signal S received by the information receiving unit 210 is expressed by the following equation (2).

&Quot; (2) "

In this case, S denotes a transmission signal, v denotes a pre-selected codeword, and x _A denotes a transmission-side binary bit key.

In operation S320, the error calculation unit 220 calculates the error value based on at least one of the transmission signal S, the pre-stored reception side binary bit key x _B , and a predetermined parity check matrix c ^T , And a binary bit error e 'indicating a difference between the binary bit key x _A and the receiving side binary bit key x _B.

Now, one embodiment of step S320 will be described in more detail with reference to FIG.

4 is a flowchart for explaining a step of calculating a binary bit error in a binary bit key estimation method for information adjustment of a continuous variable quantum key distribution, according to an embodiment of the present invention.

As shown in FIG. 4, step S320 includes steps S321, S323, and S325.

Step S321 may refer to a step in which the error calculation unit 220 performs an XOR operation on the transmission signal S and the pre-stored reception-side binary bit key x _B to generate a first calculation value.

Hereinafter, the meaning of the first calculation value generated in step S321 will be described with reference to Equation (3).

&Quot; (3) "

는 제1 연산값, S는 송신 신호, x_B는 수신단측 이진 비트키, e'은 이진 비트 오류, x_A는 송신단측 이진 비트키, v는 미리 선택된 임의의 부호어를 의미한다.At this time,

A first calculation value, S is the transmitted signal, x _B is the receiver-side bit binary key, e 'is the binary bit error, x is the transmitting end _A side-bit binary key, v; means any pre-selected codeword.

관계가 성립하고, 상술한 수학식 2에서와 같이,

관계가 성립하기 때문에, 제1 연산값(

)은 상술한 수학식 3에서와 같이

와 등가관계가 성립하게 된다.As in the above-mentioned equation (1)

, And as in the above-mentioned formula (2)

Since the relationship is established, the first calculation value (

Is expressed by Equation (3)

And so on.

을 정리하면, 상술한 수학식 3에서와 같이

가 도출될 수 있다.At this time, based on the nature of the XOR operation

, As shown in Equation (3)

Can be derived.

)는 이진 비트 오류(e') 및 미리 선택된 임의의 부호어(v) 간의 XOR 연산 결과(

)와 등가관계가 성립하게 된다.As a result, the first calculation value (

) Represents the result of the XOR operation between the binary bit error (e ') and the preselected arbitrary codeword (v)

). ≪ / RTI >

)을 행렬곱 연산하여 제2 연산값을 생성하는 단계를 의미할 수 있다.In step S323, the error calculator 220 calculates a first calculation value (< RTI ID = 0.0 >

) May be multiplied by a matrix to generate a second calculation value.

)과 이진 비트 오류(e') 및 미리 선택된 임의의 부호어(v) 간의 XOR 연산 결과(

)는 서로 등가 관계인 점을 감안하여 S323 단계를 통해 생성되는 제2 연산값의 의미를 아래 수학식 4를 통해 설명한다.At this time, as described above, the first calculation value (

), A binary bit error (e ') and a pre-selected arbitrary codeword (v)

) Are equivalent to each other, the meaning of the second calculation value generated in step S323 will be described with reference to Equation (4) below.

&Quot; (4) "

는 제2 연산값, c^T는 기설정된 패리티 체크 행렬, e'는 이진 비트 오류, v는 미리 선택된 임의의 부호어를 의미한다.At this time,

C ^T denotes a predetermined parity check matrix, e 'denotes a binary bit error, and v denotes a pre-selected codeword.

)과

는 서로 등가관계가 성립하게 된다.At this time, since the pre-selected arbitrary codeword v is a randomly selected codeword among a plurality of codewords for which 0 is multiplied by the parity check matrix c ^T ,

)and

Are equivalent to each other.

)과

가 서로 동일한 이유는 고전 통신에서 기공지된 신드롬 복호화(Syndrome Decoding) 방법에서와 동일하므로 그 구체적인 설명은 생략한다.For example, the second calculated value (

)and

Are the same as those in the syndrome decoding method well known in the classical communication, and a detailed description thereof will be omitted.

)에 대응되는 이진 비트 오류(e')를 결정하는 단계를 의미할 수 있다.In step S325, the error calculator 220 calculates a second calculation value (" 0 ") based on a lookup table stored in advance

(E ') corresponding to the binary bit error < RTI ID = 0.0 > (e) < / RTI >

)은

와 같은 값이기 때문에, S325 단계에서 오류 산출부(220)에 미리 저장된 룩업 테이블(Lookup Table)은 제2 연산값(

)과 이진 비트 오류(e')를 서로 대응되도록 매칭하여 저장한 테이블을 의미할 수 있다.As in the above-described equation (4), the second calculation value

)silver

The lookup table stored in advance in the error calculating unit 220 in step S325 is equal to the second calculated value

) And a binary bit error (e ') corresponding to each other and storing them.

)이 A인 경우 이진 비트 오류(e')는 a임이 미리 저장될 수 있다.For example, the above-described lookup table includes a second calculation value (

) Is A, the binary bit error (e ') can be stored in advance as a.

)은 고전 통신에서 기공지된 복호화 방법인 신드롬 복호화(Syndrom Decoding) 방법에서 정의하는 신드롬(Syndrom)을 의미할 수 있으며, 이 경우 미리 저장된 룩업 테이블은 신드롬 복호화 방법에서 정의하는 신드롬 룩업 테이블을 의미할 수 있으며, 신드롬 복호화 방법에서 신드롬과 신드롬 룩업 테이블을 활용하여 이진 비트 오류(e')를 결정하는 보다 구체적인 방법은 기 공지된 바와 같으므로 그 설명은 생략한다.For example, the second calculation value (

May refer to a syndrome defined in a syndrom decoding method which is a known decoding method in classical communication. In this case, the pre-stored lookup table means a syndrome lookup table defined by the syndrome decoding method And a more specific method of determining the binary bit error (e ') by using the syndrome and the syndrome look-up table in the syndrome decoding method is the same as that described above, so that the description thereof is omitted.

Continuing with FIG. 3, step S330 will be described.

Step S330 may mean that the binary bit key estimator 230 estimates the transmitter side binary bit key x _A based on the receiving side binary bit key x _B and the binary bit error e ' have.

In more detail, step S330 may include the step of estimating the receiver-side bit binary key (x _B) and a binary bit error (e ') an XOR operation to the transmitting end side binary bit key (x _A).

As shown in Equation (1) above, the transmitter side binary bit key (x _A ) can be generated by XORing the reception side binary bit key (x _B ) and the binary bit error (e ').

As a result of performing steps S310, S320 and S330, the receiving end 20, Bob can estimate the transmitting end side binary bit key x _A , so that the transmitting end 10, Alice and the receiving end 20, The binary bit key can be shared.

Referring now to FIG. 5, a method and apparatus for binary bit key estimation for information coordination of continuous variable quantum key distribution in accordance with an embodiment of the present invention will be described.

At this time, the binary bit key estimating apparatus 200 for information adjustment of the continuous variable quantum key distribution according to the embodiment of the present invention may be included in the receiving terminal 20 (Bob) shown in FIG.

As described above, the transmitting terminal 10, Alice and the receiving terminal 20, Bob respectively hold the transmitting-end initial quantum key X and the receiving-end initial quantum key X 'through the continuous variable quantum key distribution, Each of the transmitting end 10 and the receiving end 20 and the receiving end 20 quantizes the initial quantum keys X and X 'in the same rule to generate a binary bit key that can be used as an encryption key for quantum communication As a result, the transmitting terminal 10, Alice holds the transmitting terminal side binary bit key x _A , and the receiving terminal 20, Bob holds the receiving terminal side binary bit key x _B.

Thereafter, the transmitter 10 (Alice) transmits a pre-selected random code, which is a randomly selected codeword among a plurality of codewords defined in the transmission side binary bit key (x _A ) and a linear block code (V) to generate a transmission signal (S), and then transmits the transmission signal (S) to the receiving end (20, Bob) through the classical channel.

)을 생성하고, 제1 연산값(

)에 신드롬 복호화 방법을 적용하여 이진 비트 오류(e')를 결정할 수 있으며, 그 뒤, 수신단(20, Bob)은 수신단측 이진 비트키(x_B)와 이진 비트 오류(e')를 서로 XOR 연산하여 송신단측 이진 비트키(x_A)를 추정할 수 있다.Thereafter, the receiving end 20, Bob performs an XOR operation on the transmission signal S and the receiving end side binary bit key x _B to calculate a first calculation value (

), And generates a first calculation value (

) By applying the syndrome decoding method, can determine), the back, a receiver (20, Bob) is the receiver-side binary bit key (x _B) and a binary bit error (e 'binary bit error (e to XOR a) with each other And can estimate the transmission side binary bit key (x _A ).

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but many variations and modifications may be made without departing from the scope of the present invention. It will be understood that the invention may be practiced.

10: Transmitter (Alice)
20: Receiver (Bob)
200: Binary bit key estimator for information adjustment of continuous variable quantum key distribution
210:
220: Error calculation unit
230: a binary bit key

Claims (8)

Receiving, by the information receiving unit, a transmission signal generated based on the transmitting-end binary bit key from the transmitting terminal;
Wherein the error calculation unit calculates a difference between the transmission side binary bit key and the reception side binary bit key based on at least one of the transmission signal, a pre-stored reception side binary bit key, and a predetermined parity check matrix. Calculating a binary bit error; And
Estimating the transmitting-side binary bit key based on the receiving-side binary bit key and the binary bit error,
The step of calculating the binary bit error comprises:
Performing an XOR operation on the transmission signal and the pre-stored reception-side binary bit key to generate a first calculation value;
Generating a second operation value by performing a matrix multiplication of the first operation value on the predetermined parity check matrix; And
And determining the binary bit error corresponding to the second computation value based on a pre-stored lookup table. ≪ Desc / Clms Page number 21 > The method according to claim 1,
The transmission signal includes:
Wherein the binary bit key is a signal generated by performing an XOR operation on the transmission-side binary bit key and a pre-selected arbitrary codeword. delete The method according to claim 1,
The step of estimating the transmission-side binary bit key comprises:
And estimating the transmitter side binary bit key by performing an XOR operation on the receiver side side binary bit key and the binary bit error, thereby estimating a binary bit key for continuous variable quantum key distribution. An information receiving unit for receiving a transmission signal generated based on a transmitting terminal side binary bit key from a transmitting terminal;
A binary bit error indicating a difference between the transmission side binary bit key and the reception side binary bit key based on at least one of the transmission signal, a pre-stored reception side binary bit key, and a predetermined parity check matrix An error calculating section for calculating the error; And
And a binary bit key estimator for estimating the transmitter-side binary bit key based on the receiving-side binary bit key and the binary bit error,
The error calculator calculates,
An XOR operation is performed on the transmission signal and the pre-stored reception-side binary bit key to generate a first calculation value,
Generating a second operation value by performing a matrix multiplication of the first operation value with the predetermined parity check matrix,
And determines the binary bit error corresponding to the second computation value based on a pre-stored lookup table. 6. The method of claim 5,
The transmission signal includes:
Which is a signal generated by performing an XOR operation on the transmission-side binary bit key and a pre-selected arbitrary codeword, in order to adjust the information of the continuous variable quantum key distribution. delete 6. The method of claim 5,
Wherein the binary bit key estimator comprises:
And estimating the transmitting-side binary bit key by performing an XOR operation on the receiving-side binary bit key and the binary bit error.

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