Electronics and Telecommunications Research Institute

Lg Electronics Inc.

Changho Hong

Daesung Kwon

Jingak Jang

Osung Kwon

Se Wan Ji

Haeng-Seok Ko

Younchang Jeong

Nayoung Kim

Eun Ji Kim

Seok Koo Kim

Youngjoon Lee

Kyujin Choi

Geunsu Kim

Sooho Bang

Baekbong Pyo

Taemin Kwon

Sangmo Kim

Geunsu Lee

Seok Ki Kim

Doochan Jung

Hyunyun Hwang

A quantum entity authentication apparatus and method. The quantum entity authentication apparatus includes a quantum state preparation unit for preparing an authentication quantum state that is generated based on an authentication key previously shared with an entity, a quantum channel verification unit for transmitting a quantum state, generated by performing an operation using a prestored unique operator on the authentication quantum state, to a quantum measurement device, and for verifying security of a quantum channel by using a result of Bell measurement and the authentication quantum state, the result of Bell measurement being revealed by the quantum measurement device for the quantum state, and a quantum entity authentication unit for, when the security of the quantum channel is verified, authenticating the entity using the result of the Bell measurement and the unique operator.

Quantum entity authentication apparatus and method

An apparatus and method for quantum direct communication using single qubits. The apparatus includes a quantum state preparation unit for preparing quantum states including a message state prepared using pairs of single qubits based on a bit of a message to be sent to a communication partner, an authentication state prepared using random qubit pairs, and a verification state prepared using random qubit pairs, a quantum state communication unit for transmitting the quantum states to the communication partner and measuring a quantum state of a message received from the communication partner, an authentication unit for authenticating, using the authentication state, the communication partner depending on whether an authentication key previously shared with the communication partner is possessed, a verification unit for verifying security of a quantum channel using the verification state, and a message restoration unit for restoring the received message using the message state.

Apparatus and method for quantum direct communication using single qubits

A quantum key distribution (QKD) node apparatus and a QKD method therein. The QKD node apparatus may include a QKD module for generating quantum keys and quantum key IDs, a quantum key synchronization management module for storing the quantum keys and the quantum key IDs as outbound and inbound quantum keys in a distributed manner and sharing the outbound and inbound quantum keys with a second QKD node apparatus, and a quantum key orchestration module for delivering a master key and a master key ID to a secure application connected therewith in response to a request for the master key with the ID of a second secure application and delivering a packet including the master key encrypted with the outbound quantum key shared with the second QKD node apparatus, the master key ID, and a quantum key ID, to the second QKD node apparatus.

Quantum key distribution node apparatus and method for quantum key distribution thereof

A single-photon detection method and apparatus. The single-photon detection method detects a single photon using a single-photon detection apparatus, and includes generating an output signal through a photon detector by receiving a light signal as an input, generating a negative voltage comparison result through a negative voltage comparator by receiving the output signal as an input, and generating a photon detection result based on the negative voltage comparison result.

Single-photon detection method and apparatus

An apparatus and method for a reliable quantum signature. The method using the apparatus for a reliable quantum signature includes preparing a quantum signature by sharing a first secret key and a first Bell state with a signer's terminal device and by sharing a second secret key and a second Bell state with a verifier's terminal device; signing, by the signer's terminal device, a message with the quantum signature using a first encoding value, the first secret key, and the first Bell state; verifying, by the apparatus, the quantum signature of the message using the first encoding value, the first secret key, and the first Bell state; and finally verifying, by the apparatus, the quantum signature of the message using the verifier's terminal device, a second encoding value, a third encoding value, the second secret key, and the second Bell state.

Apparatus and method for reliable quantum signature

Disclosed is a terminal set including a mobile terminal and an assistance device configured to be selectively coupled to the mobile terminal in order to complement performance degradation of a cap sensor of the mobile terminal due to the auxiliary device. The mobile terminal includes a first cap sensor configured to sense an approach of an external object; and the assistance device includes a cover member having an auxiliary display, a seating member connected with an edge of the cover member and forming a seating area for the mobile terminal to sit therein, a mobile terminal coupling terminal provided at the seating member and connected with a power supply terminal of the mobile terminal, and a second cap sensor provided at the seating area and connected with the mobile terminal coupling terminal to sense the approach of the external object.

Mobile terminal and assistance device coupled to the same

An authentication apparatus and method for quantum cryptography communication. The quantum cryptography communication authentication method is performed using quantum cryptography communication authentication apparatuses, and includes transmitting, by a first quantum cryptography communication authentication apparatus, a quantum state to a second quantum cryptography communication authentication apparatus by selecting a first basis, and measuring, by the second quantum cryptography communication authentication apparatus, the quantum state by selecting a second basis, and performing, by the first quantum cryptography communication authentication apparatus and the second quantum cryptography communication authentication apparatus, authentication by revealing the first basis and the second basis and by comparing sifted keys generated from a common basis between the first basis and the second basis with each other.

Authentication apparatus and method for quantum cryptography communication

A quantum direct communication with user authentication and an apparatus using the same. The quantum direct communication method includes performing verification of security of a quantum channel using a preset channel verification probability and a quantum state source generated by a receiver of quantum direct communication, performing user authentication using one or more of a preset user authentication probability, the quantum state source, and an authentication key shared between the receiver and a sender, stopping quantum direct communication and resetting the quantum channel when the verification of security of the quantum channel fails, and stopping quantum direct communication when the user authentication fails.

Quantum direct communication method with user authentication and apparatus using the same

A mobile terminal can include a terminal body having a display unit disposed on one surface thereof; a frame supporting the display unit; a metal member spaced apart from the frame and exposed to an outside of the mobile terminal; a plurality of connecting members connecting the metal member to the frame and grounding the metal member; and an antenna unit disposed adjacent to the frame and including a radiator configured to radiate wireless signals in a first frequency band, in which the metal member is divided into specific areas by the plurality of connecting members, and one area located adjacent to the radiator, is configured to generate a parasitic resonance at a second frequency band different from the first frequency band, and the plurality of connecting members connected to the metal member are spaced apart from one another at different intervals.

Mobile terminal

An apparatus and method for multi-user quantum key distribution. The method for multi-user quantum key distribution is performed using a multi-user quantum key distribution apparatus and a quantum key client device, and includes generating, by the multi-user quantum key distribution apparatus, transmission qubit pairs based on a key bit string of a shared key to be distributed to the quantum key client device, measuring, by the quantum key client device, the transmission qubit pairs, received from the multi-user quantum key distribution apparatus through a quantum channel, based on a measurement basis, verifying security of the quantum channel using the transmission qubit pairs, and if the security has been verified, decoding qubit measurement values of the transmission qubit pairs into the shared key.

Apparatus and method for multi-user quantum key distribution

There is disclosed a mobile terminal comprising a body; a ground of a printed circuit board loaded in the body; a data port located in the body to have an external input terminal inserted therein and connected with the ground; a metallic member defining an exterior of the body and comprising a slit; a feeding portion connected with a first point of the metallic member and configured to supply power; a first ground line connected with the ground at a second point located between the first point of the metallic member and the slit; and a second ground line connected with the data port connected with the ground when the external input terminal is inserted in the data port, so that the mobile terminal has to include no additional switch to reduce the number of the components and the antenna of the mobile terminal may be selectively and structurally connected without the algorithm configured to manipulate the switch by sensing that the external input terminal is inserted in the data port to operate the switch to minimize the expense increase cost to improve the antenna performance.

A mobile terminal including a terminal body having a display unit disposed on one surface thereof; a frame supporting the display unit; a metal member spaced apart from the frame and exposed to an outside of the mobile terminal; a plurality of connecting members connecting the metal member to the frame and grounding the metal member; and an antenna unit disposed adjacent to the frame and including a radiator radiating wireless signals in a first frequency band. Further, the metal member is divided into specific areas by the connecting members, and one area located adjacent to the radiator, generates a parasitic resonance at a second frequency band different from the first frequency band, and a frequency band of the antenna unit is shifted to a third frequency band including the first frequency band by the metal member and the radiator when a dielectric is placed adjacent to the metal member.

Growing community of inventors

Seoul, South Korea

Changho Hong