Electronics and Telecommunications Research Institute

Yonsei University

Korea Telecommunication Authority

Hun Sik Kang

In Ki Hwang

Sok Kyu Lee

Sang Rok Moon

Joon Ki Lee

Do Young Kim

Heejung Yu

Sun Hyok Chang

Dong Hyun Bae

Il Gu Lee

Seung-Woo Lee

Jung Hak Kim

Jung-yeol Oh

Jung Bo Son

Sok-Kyu Lee

Seung Woo Lee

Min Ho Cheong

Ji Eun Kim

Eun-Young Choi

Eun Young Choi

Jae Ho Shin

Jong Ee Oh

Joon Young Huh

Dae Hwan Hwang

Chan Ho Yoon

Sae Kyoung Kang

Seok Hyun Yoon

HyunJoo Choi

Yeong Ho Park

DongHyun Bae

Young Sik Baek

Sang Man Lee

Dong Bum Jung

SeungWon Kang

Jein Baek

Proposed are an apparatus and a method for designing codes by using polar and algebraic codes. The operating method of the apparatus for designing a code may include a step of identifying a polar code defined as at least one information set, a step of identifying a parity matrix of the polar code, a step of identifying a vector corresponding to the polar code, a step of identifying a row that is representable in a way by linearly combining each row of the parity matrix, a step of identifying a specific binarization matrix in which the representable row does not exist, a step of generating a transformed parity matrix by adding the specific binarization matrix to the parity matrix and a step of generating a pre-code corresponding to the transformed parity matrix.

Apparatus and method for designing codes by using polar and algebraic codes

Provided is a coherent optical communication system including a coherent optical transmitter and a coherent optical receiver, and more particularly, when a polarization time block code is used, the complexity for performing a polarization time block decoding scheme of the coherent optical receiver is minimized.

Coherent optical communication system using polarization time block code

Provided are a method and an apparatus for optimizing the performance of an optical transceiver, and the gist is as follows: receiving an optical input and converting the optical input into electrical signals; receiving a performance value and a reference clock of the electrical signals from a DSP part; generating a plurality of clocks by using the reference clock; determining ADC sampling timings of a plurality of ADCs on the basis of phases of the plurality of clocks applied to the plurality of ADCs; and compensating, on the basis of the determined ADC sampling timings, for differences in physical length between output signals of the plurality of ADCs.

Method and apparatus for optimizing performance of optical transceiver

Provided are a method and apparatus for registering a new terminal using chromatic dispersion distance estimation. The method of registering a new terminal, performed by a transport unit (TU), includes performing frame synchronization through a downstream packet received from a transport node (TN), identifying a position of a frequency of a spectral null and a number of frequencies of spectral nulls through analysis on a frequency spectrum of the received downstream packet, estimating a transmission distance of an optical fiber to the TN, based on the identified position of the frequency of the spectral null and the identified number of frequencies of spectral nulls, and determining a timing of transmitting a registration request message, based on the estimated transmission distance, where the discovery information message is received from the TN.

Method and apparatus for registering new terminal using chromatic dispersion distance estimation

Disclosed herein is an optical transmitter for generating a vestigial sideband (VSB) optical signal. The optical transmitter includes: a modulator configured based on a photonic integrated chip (PIC); an optical fiber block; and a lensed thin film filter implemented between the modulator configured based on the PIC and the optical fiber block. The PIC includes at least one grating coupler, and the lensed thin film filter is disposed so that an angle of an optical signal emitted from a first grating coupler of the PIC coincides with an angle of incident (AOI) of the lensed thin film filter to design the first grating coupler and the lensed thin film filter.

Optical transmitter based on vestigial sideband modulation

Provided are a method of low-complexity decoding based on soft decision and a computing device for performing the method. The method of low-complexity decoding based on soft decision, performed by a computing device, includes receiving a vector, in which a codeword is modulated, through a channel, determining a decoding result by sequentially applying the received vector to one or more decoding algorithms, and decoding the codeword based on an analysis on the decoding result of a detector corresponding to each of the one or more decoding algorithms.

Soft decision-based low-complexity decoding method and computing device for performing the method

A deinterleaving method and a deinterleaving system performing the same are disclosed. According to an example embodiment, a data processing method includes dividing data into first data blocks of a first number of bits, performing deinterleaving on the first data blocks, and dividing deinterleaved data into second data blocks of a second number of bits and outputting the second data blocks, wherein the first number of bits is determined based on a minimum switching unit of a deinterleaving operation and the second number of bits.

Deinterleaving method and deinterleaving system performing the same

According to one embodiment of the present invention, a cast alloy material is provided. The cast alloy material includes a matrix metal and an alloy element, wherein oxide particles in a nanometer scale are decomposed in the matrix metal, so that a new phase including a metal element that is a component of the oxide particles and the alloy element forms a band or network structure, wherein the metal element and the alloy element have a relationship of a negative heat of mixing, and wherein oxygen atoms formed by decomposition of the oxide particles are dispersed in the matrix metal and do not form an oxide with the matrix metal.

Alloy material in which are dispersed oxygen atoms and a metal element of oxide-particles, and production method for same

An optical transmission method for processing a signal based on direct detection includes setting, by an equalizer, an adaptive equalization coefficient by performing an equalization process during a training symbol field section in a frame of a received signal, performing, by a channel estimator, channel estimation to perform an equalization process of a soft output maximum likelihood sequence equalizer (MLSE) during the training symbol field section, driving the soft output MLSE, and compensating for, by the soft output MLSE, distortion of the received signal during a data symbol field section in the frame on the basis of the adaptive equalization coefficient and an estimated result value of a channel, and recovering, by an error corrector which allows soft-decision processing to be performed, the received signal by performing error correction on the received signal in which the distortion is compensated for.

Optical transmission apparatus and method for processing signal based on direct detection

Disclosed is a method of manufacturing a metal matrix composite in which oxide nanoparticles are dispersed. Metal matrix composite powders in which oxide nanoparticles are dispersed are prepared. Gibbs free energy of the oxide nanoparticles is greater than that of an oxide of a metal matrix. A bulk processed material is manufactured from the composite powders through hot forming or a cast material is manufactured by inputting the composite powder into a molten base metal and then rapidly stirring a resultant mixture. The bulk processed material or the cast material is heat-treated so that atoms of the metal matrix and atoms of the oxide nanoparticles mutually diffuse. Oxygen atoms originating from the oxide nanoparticles are diffused and dispersed in the metal matrix.

Oxygen atom-dispersed metal matrix composite and method of manufacturing the same

A method and apparatus for compensation of a chromatic dispersion through an optical compensation and an electronical compensation in optical communication. An optical communication method receives an optical signal, estimates a first transmission length based on a null component included in a frequency spectrum of the optical signal, optically compensates for a chromatic dispersion of the optical signal based on the first transmission length, estimates a second transmission length based on a null component included in a frequency spectrum of the compensated optical signal, and electronically compensates for a residual chromatic dispersion of the compensated optical signal based on the second transmission length.

Apparatus and method for equalization and compensation of chromatic dispersion in optical transmission

There is provided a Mg&#x2014;N-A based magnesium material (A is a metal or non-metal element configuring a nitride, N: nitrogen originating from the nitride). The magnesium material includes a spherical Mg&#x2014;N-A eutectic phase and nitrogen atoms are dispersed in a magnesium matrix, whereby mechanical and ignition properties of the magnesium material are improved, as compared to a magnesium material or pure magnesium material in which the nitrogen atoms are not included and only the metal or non-metal element is included.

Magnesium material and method of manufacturing the same

A method of manufacturing a metal material is provided. The method includes steps of manufacturing a metal material in which oxygen atoms are dispersed, and forming a protective coating on a surface of the metal material by using an anode oxidation treatment, wherein the oxygen atoms in the metal material are supplied to the surface of the metal material during the anode oxidation treatment, so that the metal material and the protective coating are interface-bonded to each other substantially without pores therebetween or without an interface layer in which pores are formed, thereby improving corrosion resistance, as compared to a protective coating formed on a surface of a metal material in which oxygen atoms are not dispersed.

Metal material having protective coating and method for manufacturing the same

A method and apparatus for transmitting a relay frame in a relay end are provided. The method includes: receiving a relay request frame requesting data transmission to a receive end from a transmit end; transmitting a relay response frame including information on data to be relayed to each of the transmit end and the receive end; receiving the data from the transmit end; and generating a relay frame including the data to transmit the relay frame to the receive end. According to the present invention, the data is transmitted to the receive end positioned outside a transmission coverage of the transmit end, such that a wireless LAN service coverage may be expanded, and an adjacent terminal connected to the receive end is used as the relay end, such that the transmit end that may not be connected directly to the receive end may communicate with the receive end.

Method and apparatus for transmitting relay frame in wireless communication system

A method and an apparatus for a transmitter to transmit data in a wireless communication system are provided. This method includes: generating a first signal field including at least one symbol; generating a second signal field configured by repeating at least one symbol of the first signal field; and transmitting a frame including the first signal field, the second signal field, and a data field and a first symbol of the second signal field is modulated through binary phase shift keying (BPSK) and symbols from a second symbol of the second signal field are modulated through Q-BPSK. According to the present invention, a service filed can be extended while maintaining compatibility with a wireless communication system in the related art by transmitting a frame using symbol repetition.

Growing community of inventors

Daejeon, South Korea

Hun Sik Kang