摘要:
A wireless visible light communication system is provided. The system includes optical transmitters and optical receivers for receiving optical signals, wherein each of the optical transmitters includes a first light source for generating an optical signal, and at least one light source capable of generating light which has a color equal to that of the optical signal, and has a wavelength different from that of the optical signal.
摘要:
An optical receiver for visible light communication includes a lens system for converging visible light for light communication and an optical filter for passing converged visible light to the optical receiver. A photoelectric transmission device detects data from visible light for light communication in a VLC system. An optical filter is positioned between the lens system and the photoelectric transmission device, the optical filter having a first film for transmitting visible light and a second film arranged/grown around the first film to transmit ultraviolet rays or infrared rays. A first optical detects data from visible light passing through the first film of the optical filter. A second optical detector detects the intensity of light transmitting the second film. The encoding, encoding rate or intensity of the optical transmitted signal can be adjusted in response to the detection of at least the second optical detector.
摘要:
A method for transmitting/receiving data between first and second terminals in which data can be transmitted flexibly in each particular situation, i.e. according to the network environment of terminals between which visible light communication occurs, including the type and characteristics of transmitted data. The method includes the steps of: (a) connecting a communication link between a first terminal supposed to transmit data and a second terminal supposed to receive data; (b) determining a data transmission rate to be used for data communication; (c) allocating a transmission channel of a specific band within a frequency band enabling wireless communication; (d) establishing a data transmission environment based on consideration of the transmission rate and the transmission channel; and (e) conducting data communication between the first and second terminals with reference to the data transmission environment.
摘要:
Method and device for exchanging messages in a VLC navigation system is provided, in which a map server generates a provision message in the form of visible light signals through all lamps in an area, using a PLC network, where a navigation service is provided, a terminal that wants to implement the navigation service among terminals that have received the provision message transmits a registration request message to the map server, the map server transmits a registration response message for the registration request message to the terminal, the terminal transmits a map request message including information about a destination to the map server, the map server transmits a map response message including information about a path to the destination to the terminal, and the terminal displays map information and the path.
摘要:
Method and device for exchanging messages in a VLC navigation system is provided, in which a map server generates a provision message in the form of visible light signals through all lamps in an area, using a PLC network, where a navigation service is provided, a terminal that wants to implement the navigation service among terminals that have received the provision message transmits a registration request message to the map server, the map server transmits a registration response message for the registration request message to the terminal, the terminal transmits a map request message including information about a destination to the map server, the map server transmits a map response message including information about a path to the destination to the terminal, and the terminal displays map information and the path.
摘要:
A method for transmitting/receiving data between first and second terminals in which data can be transmitted flexibly in each particular situation, i.e. according to the network environment of terminals between which visible light communication occurs, including the type and characteristics of transmitted data. The method includes the steps of: (a) connecting a communication link between a first terminal supposed to transmit data and a second terminal supposed to receive data; (b) determining a data transmission rate to be used for data communication; (c) allocating a transmission channel of a specific band within a frequency band enabling wireless communication; (d) establishing a data transmission environment based on consideration of the transmission rate and the transmission channel; and (e) conducting data communication between the first and second terminals with reference to the data transmission environment.
摘要:
Disclosed is a method for processing incoming signals of photo-detectors in a visible light communication system. The method includes: dividing symbol duration into divided durations according to an equal time interval to set the divided durations to a plurality of time slots, the symbol duration being a time required to transmit one of a symbol and a bit; receiving visible light signals through a photodiode array in a receiver; determining a gain value of each of the photodiodes during a time slot, in consideration of each photodiode area on the photodiode array during the time slot and the time slot position within the symbol duration; multiplying a gain value of each of the photodiodes by an output value of a corresponding photodiode; and summing up output values of each of the photodiodes by which the gain value has been multiplied and calculating a total of output values of the time slot.
摘要:
An apparatus for transmitting Visible Light Communication (VLC) data, in which a data processor processes data to be transmitted, a modulator modulates data received from the data processor into a signal for VLC, a light output unit outputs light of a predetermined color and includes in the light a signal of any selected one characteristic among signals of two different characteristics, and a light output controller selects at least one of the signals of different characteristics, and controls the light output unit so that a signal from the modulator is output through the signal of the selected characteristic.
摘要:
A traffic information service apparatus using an ad-hoc network and a method for controlling the same. The apparatus provides an ad-hoc network between vehicles and roadside devices, and collects/provides traffic information using the ad-hoc network. The method for providing a user with traffic information, comprising the steps of a) allowing vehicles to broadcast their registration messages to create an ad-hoc network, and creating the ad-hoc network between the vehicles on the basis of the registration messages, b) allowing a Road Side Equipment (RSE) to receive the registration messages broadcast from the vehicles, and collecting traffic information from the registration messages, and c) allowing the RSE to transmit the traffic information to a traffic information service center.
摘要:
Provided is an apparatus and method for displaying a strength of power and an expected charge completion time during wireless charging. To this end, a first electronic device, upon receiving a power request message, converts stored or wirelessly supplied power into a wirelessly-transmittable form and transmits the converted power. A second electronic device, upon receiving a charging command, determines whether being located in a distance and a position which allow charging with the first electronic device, transmits the power request message to the first electronic device, receives the converted power from the first electronic device to measure the strength of the received power, and calculates an expected charge completion time by using the detected strength of power, if the second electronic device is located in the distance and position which allow charging.