Kookmin University

Yeong Min Jang

Van Trang Nguyen

Ngoc Huy Nguyen

Chang Hyun Hong

Ahmed Md Faisal

Van Nguyen Trang

Van Thang Nguyen

Minh Duc Thieu

Ngoc Nguyen Huy

Tung Lam Pham

Thieu Minh Duc

Utama Ida Bagus Krishna Yoga

An optical signal transmission method according to an embodiment of the disclosure is an optical signal transmission method in which a processor performs at least part of each operation, and may include an operation of receiving a data stream, an operation of separating at least part of the data stream into three channels, modulating the separated data streams respectively according to M-ary frequency shift keying (M-FSK) scheme so as to produce an FSK modulated signal, an operation of combining a plurality of FSK modulated signals modulated respectively in the three channels, and producing a color modulated signal according to a bit-color mapping table set in advance, and an operation of transmitting the color modulated signal by controlling a light source of the same optical channel based on the color modulated signal.

Apparatus and method for optical wireless communication based on color M-ary frequency shift keying

This application relates to a battery test apparatus and an operating method thereof to check whether the direction of battery cells provided inside a battery tray is correct by implementing a computer vision AI algorithm. In one aspect, the method includes performing a first test for checking whether a battery tray has been correctly aligned with the battery test apparatus. The method may also include capturing a battery tray image including a plurality of battery cells using a camera upon alignment of the battery tray. The method may further include obtaining related information on battery cells from the battery tray image, and loading the related information on the battery cells. The method may further include performing a second test for checking whether directions of the battery cells are correct.

Apparatus for checking battery position and operating method thereof

A method of modulating an optical camera communication (OCC) signal by an OCC transmission node in an OCC system includes acquiring a binary data signal, grouping the binary data signal for every k bits to convert the binary data signal into a global phase shift signal having an integer value from 0 to M−1 (=2−1), generating a data signal group by mapping the global phase shift signal to first to Mth mapping sequences in the form of an n*M/2-bit sequence based on a preset symbol group mapping table, generating a pulse wave signal by modulating the data signal group, and blinking each of a plurality of light sources included in the OCC transmission node according to the pulse wave signal. Accordingly, performance of the communication system may be improved.

Communication method and device in optical camera communication system

An optical communication-based image processing system is disclosed. The system may include a transmitter having at least one light emitting element and a receiver having a rolling shutter camera. As the system is provided, a rolling shutter effect may be improved.

Method and apparatus for processing image based on optical communication, and computer-readable recording medium with program therefor

An optical wireless transmission device according to an embodiment of the present invention comprises: a modulation unit for receiving input of a first input signal and outputting a first output signal; and a light source control unit for controlling a first light source in accordance with the first output signal. The first output signal repeats '0' and '1' in a first phase during clock time if a binary value of the first input signal is 0, and repeats &#x201c;0&#x201d; and &#x201c;1&#x201d; in a phase opposite from the first phase during the clock time if a binary value of the first input signal is 1.

RoI-based optical wireless communication method and device

A communication device effectively transmits high-speed data while being less affected by restrictions of an environment by adjusting a communication channel depending on an optical communication environment.

Communication device for adjusting communication channel depending on optical communication environment and communication method using the same

A device for transmitting a signal according to some embodiments of the present disclosure relates to a device for transmitting a signal using a hybrid waveform. The device may include a modulator configured to modulate an input signal and a signal transmitter configured to transmit the modulated final transmission signal through an LED light source, wherein the modulator is configured to modulate first information into a pulse signal based on frequency shift keying (FSK), and modulate second information into an orthogonal frequency division multiplexing (OFDM) signal, wherein the first information and the second information are different from each other and mix the pulse signal and the OFDM signal into one waveform to generate the final transmission signal.

Device for communicating signal of hybrid waveform based on M-FSK and OFDM

An optical wireless transmission method according to an embodiment of the present invention comprises the steps of: a modulator receiving transmission data and a transmission image; the modulator generating a reference image on the basis of the transmission image; the modulator generating a data embedded image on the basis of the transmission data and the transmission image; and the transmitter sequentially transmitting the reference image and the data embedded image by means of a light source panel.

MIMO-OFDM of optical wireless system using screen

Provided are a communication method and apparatus using a hybrid modulation scheme in a communication system. The communication node uses a hybrid modulation scheme in the communication system and includes a processor, a first light-emitting diode (LED) array configured to transmit a first signal by blinking a first LED set according to control of the processor, a second LED array configured to transmit a second signal by blinking a second LED set according to control of the processor, and a memory configured to store one or more instructions executed by the processor. Therefore, performance of the communication system can be improved.

Communication method and apparatus using hybrid modulation scheme in communication system

An optical wireless communication apparatus includes: a modulator for generating a reference signal including periodically repeating binary zeros and ones, receiving an input of a first binary data signal, and outputting a second binary data signal, wherein the second binary data signal has the same frequency as the reference signal, and has the same phase as the reference signal when the first binary data signal comprises binary zeros and has an opposite phase to the reference signal when the first binary data signal comprises binary ones, or has the same phase as the reference signal when the first binary data signal comprises binary ones and has an opposite phase to the reference signal when the first binary data signal comprises binary zeros, and a transmitter for turning a first light source on or off according to the reference signal, and turning a second light source on or off according to the second binary data signal.

S2-PSK optical wireless communication method and apparatus

A DSM-PSK optical wireless transmission method includes the steps of: receiving a binary data signal, allowing a modulator to convert the binary data signal into a global phase shift signal, generating a reference signal group including M number of pulse signals having the same period, the same duty ratio of d/M, mutually different phases, and a determined sequence, generating a data signal group including M number of pulse signals having a determined sequence, the pulse signals having been obtained by phase-shifting the reference signal group according to the global phase shift signal, flickering each light source of a reference light source group including M number of light sources having a determined sequence, according to each pulse signal of the reference signal group, and flickering each light source of a data light source group including M number of light sources having a determined sequence, according to each pulse signal of the data signal group.

DSM-PSK optical wireless transmission method and device

The present invention relates to an image sensor communication (ISC) system and method for enabling communication between an LED and a rolling shutter camera using a rolling shutter modulation method. The image sensor communication system according to an embodiment of the present invention comprises: a coding unit for coding transmission data to be transmitted; an LED which is turned on/off according to the transmission data coded in the coding unit; a rolling shutter camera for continuously photographing, at each of a plurality of rows in a rolling shutter manner, on/off images according to the on/off of the LED; an image processing unit for generating brightness signals according to brightness values of the on/off images of the LED photographed at each of the plurality of rows by the rolling shutter camera; and a data extraction unit for extracting the transmission data from the brightness signals of the on/off images of the LED generated by the image processing unit.

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Seoul, South Korea

Yeong Min Jang