Abstract:
Disclosed herein is an apparatus and method for controlling a fault in a lighting network The apparatus includes power selection units respectively provided in a plurality of lighting units connected to one another over a network, each power selection unit being configured to compare a reference voltage with an output voltage sensed from power supply signals input from power supply units respectively provided in a lighting unit, located ahead of a faulty lighting unit, and the faulty lighting unit if a fault occurs in the lighting unit, and to select supply power to be supplied to the faulty lighting unit. Lighting control units control driving of the faulty lighting unit using the selected supply power.
Abstract:
The present invention relates to an inter-vehicle communication apparatus and method using visible light communication. The inter-vehicle communication apparatus using visible light communication includes a spreading code application unit for applying a spreading code to transmission data desired to be transmitted, and a transmission unit for generating a transmission frame based on the transmission data to which the spreading code is applied, and transmitting the transmission frame via a lighting lamp of a vehicle. The transmission frame includes a preamble field required to synchronize the transmission frame, a data field required to transmit the transmission data, and a position field required to provide hopping information of the transmission data.
Abstract:
Disclosed herein is a method of performing visible-light wireless communication using light-emitting diode (LED) illumination, in which Variable Pulse Position Modulation (VPPM) is used for low-speed data transmission and dimming of illumination, and orthogonal frequency division multiplexing (OFDM) modulation is used in a VPPM on period for high-speed data transmission.
Abstract:
Disclosed herein is visible light communication technology having improved reception performance regardless of dimming control of lighting based on VPPM signals. A visible light communication apparatus includes a preamble generator for generating a preamble signal, a header generator for generating a PHY header, which includes information about the physical layer of a transmission packet and dimming information including the target dimming level of the transmission packet, a fixed dimming VPPM modulator for modulating the PHY header into a first VPPM signal according to a predetermined ratio, a transmission unit signal processor for generating transmission data by performing signal processing for data to be transmitted, a variable dimming VPPM modulator for modulating the transmission data into a second VPPM signal having the target dimming level of the transmission packet, and a signal synthesizer for forming the transmission packet by combining the first and second VPPM signals.
Abstract:
Disclosed herein are an apparatus and method for controlling a lighting network. The apparatus for controlling lighting network includes a control device and a plurality of control gears. The control device generates and transfers commands to control lighting. The plurality of control gears receives the commands from the control device and control lighting. The control device assigns a right to use a lighting network to the control gears, and the control gears send information about a change in a lighting state or error details to the control device using the right to use a lighting network.
Abstract:
Disclosed herein are an apparatus and method for sensing an error and a variation in Light-Emitting Diode (LED) lighting. In the method, a PWM signal including required light emission information is generated. Tail data including operation information is generated. A CRC value based on the tail data is also generated. A tail-CRC signal is generated by combining the tail data with the CRC value. Finally, a PWM-tail signal is generated by combining the tail-CRC signal with the PWM signal.
Abstract:
Disclosed herein are a visible light communication method and apparatus. The visible light communication method includes determining whether a current location is the start of a symbol of a transmission signal, setting a sample index, a signal accumulated value for an accumulation region of a front half portion of the symbol, and a signal accumulated value for an accumulation region of a rear half portion of the symbol, determining whether the sample index belongs to an accumulation region of the front or rear half portion of the symbol, and accumulating samples of the transmission signal in accordance with the location to which the sample index belongs, determining whether a current location corresponds to the end of the symbol, and outputting a Variable Pulse Position Modulation (VPPM) communication signal corresponding to the transmission signal.
Abstract:
Disclosed herein is an LED lighting control apparatus and method based on visible light communication. The LED lighting control apparatus includes lighting information collection means for collecting status information about lighting means and environmental information about surroundings of the lighting means, and transmitting the collected information to lighting control means. The lighting information collection means includes a visible light reception processing unit for receiving the status information about the lighting means contained in a visible light signal emitted from the lighting means, a lighting information analysis unit including a plurality of environmental information sensors for detecting the environmental information about the surroundings of the lighting means, the lighting information analysis unit analyzing the environmental information detected by the environmental information sensors, and a lighting information control unit for collecting the status information and the analyzed environmental information and transmitting the collected information to the lighting control means.