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Hwang, Daejeon-City

Dae-Hwan Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20090122804MEDIA ACCESS CONTROL APPARATUS AND METHOD FOR GUARANTEEING QUALITY OF SERVICE IN WIRELESS LAN - A media access control (MAC) apparatus and corresponding methods for guaranteeing quality-of-service in a wireless local area network (LAN) are presented. The MAC method includes the steps of extracting, performing, determining, a first transmitting step, and a second transmitting step. The extracting step includes extracting a user priority from a frame received from an upper layer and separately storing a voice frame and a non-voice frame according to an access category (AC). The performing step includes independently performing backoff operations for the voice frame and the non-voice frame. The determining step includes determining whether the backoff operations for the voice frame and the non-voice frame have simultaneously ended. The first transmitting step includes transmitting the voice frame having a higher priority first and performing the backoff operation for the non-voice frame if the backoff operations have simultaneously ended. The second transmitting step includes transmitting a frame whose backoff operation ends if the backoff operations have not simultaneously ended.05-14-2009
20090207825MEDIA ACCESS CONTROL APPARATUS AND METHOD FOR GUARANTEEING QUALITY OF SERVICE IN WIRELESS LAN - A media access control (MAC) apparatus and corresponding methods for guaranteeing quality-of-service in a wireless local area network (LAN) are presented. The MAC method includes the steps of extracting, performing, determining, a first transmitting step, and a second transmitting step. The extracting step includes extracting a user priority from a frame received from an upper layer and separately storing a voice frame and a non-voice frame according to an access category (AC). The performing step includes independently performing backoff operations for the voice frame and the non-voice frame. The determining step includes determining whether the backoff operations for the voice frame and the non-voice frame have simultaneously ended. The first transmitting step includes transmitting the voice frame having a higher priority first and performing the backoff operation for the non-voice frame if the backoff operations have simultaneously ended. The second transmitting step includes transmitting a frame whose backoff operation ends if the backoff operations have not simultaneously ended.08-20-2009
20100082335SYSTEM AND METHOD FOR TRANSMITTING AND RECEIVING WIDEBAND SPEECH SIGNALS - The system for transmitting and receiving a wideband speech signal includes an A/D converter for receiving an analog speech signal to convert it into a digital speech signal, a transmitter analysis filter for receiving the digital speech signal and dividing it into a baseband signal and an enhancement residual band signal, a standard baseband encoder for accepting the baseband signal and coding it using an ITU-T encoder, an additional baseband encoder for reducing standard coding distortion in the baseband signal, an enhancement residual band encoder for coding a signal obtained by removing the coded baseband signal from the original digital speech signal, and an IP network interface for multiplexing the coded standard and additional baseband signals and enhancement residual band signal.04-01-2010

Patent applications by Dae-Hwan Hwang, Daejeon-City KR

Dae Ii Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100055599METHOD OF PREPARING TONER HAVING CORE-SHELL STRUCTURE AND TONER PREPARED USING THE SAME - A method of preparing a toner having a core-shell structure. The method includes: preparing a mixture by mixing a resin with acid groups, a coloring agent and at least one additive with an organic solvent, and neutralizing the acid groups of the resin with a base; forming a micro-suspension solution by adding the mixture to a dispersion medium; forming a toner core by removing the organic solvent from the micro-suspension; and forming a toner complex having a core-shell structure by seed-polymerizing at least one monomer on the surface of the toner core. Thus, the toner that can prevent hot offsets, improve storage stability at a high temperature and improve charge stability against environment changes can be prepared with reduced costs according to the method.03-04-2010
20100239972TONER USING RESIN HAVING ACTIVE HYDROGEN-CONTAINING GROUP AND METHOD OF PREPARING THE SAME - Provided are a toner using a resin having an active hydrogen-containing group, and a method of preparing the toner. The toner using a resin having an active hydrogen-containing group includes a binder resin (A), a cross-linked resin including a THF insoluble content of 99-100 weight %, a colorant, and at least one additive. The cross-linked resin is arranged in the form of a plurality of islands in each particle of the toner.09-23-2010
20100272471ELECTROPHOTOGRAPHIC TONER AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS USING THE SAME - Provided are an electrophotographic toner and an electrophotographic image forming apparatus using the same. The electrophotographic toner includes: parent toner particles including a binder resin, a colorant, a releasing agent, and a charge control agent; and barium titanate external additives having an average primary particle diameter in the range of about 50 to about 150 nm, an average shape factor (SF1) in the range of about 100 to about 120, a shape factor in the range of about 0.96 to about 1, and an aspect ratio in the range of about 0.89 to about 1, and added to the surface of the parent toner particles.10-28-2010
20110033207TONER USING RESIN BEING INSOLUBLE IN ORGANIC SOLVENTS AND METHOD FOR PREPARING THE SAME - A toner using an organic solvent-insoluble resin and a method of preparing the same. The toner includes: a binder resin that comprises an organic solvent-insoluble resin and an acid group-containing resin, a coloring agent, and at least one additive, wherein the organic solvent-insoluble resin is a crosslinked polyester resin or a cyclic olefin co-polymer (COC) resin, and the ratio of the organic solvent-insoluble resin to the acid group-containing resin is in the range of 5:95 to 40:60 on a weight basis. The toner can be applied to an electrophotographic imaging apparatus.02-10-2011

Dae Il Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100098462METHOD OF PREPARING TONER USING MICRO-SUSPENSION PARTICLES AND TONER PREPARED USING THE METHOD DIGITAL IMAGE DATA - A method of preparing a toner using a micro-suspension particle, includes preparing a mixture by mixing a resin having acidic groups, a master batch of coloring pigment, and at least one additive with an organic solvent, and then neutralizing the acid groups of the resin with a base; forming a micro-suspension by adding the prepared mixture to a dispersion medium; and forming a toner composition by removing the organic solvent from the prepared micro-suspension. Therefore, the method of preparing a toner using the disclosed micro-suspension particle and a toner prepared using the same can save manufacturing costs, and can improve charging ability and cleaning properties of the toner.04-22-2010
20100216069METHOD OF PREPARING TONER - Provided is a method of preparing a toner, the method including: preparing a solvent emulsion by stirring a medium including a polar medium, an organic solvent, and a surfactant; adding toner components including a resin and a pigment to the solvent emulsion; removing the organic solvent from the solvent emulsion including the toner components; and collecting a toner particle from the solvent emulsion from which the organic solvent is removed.08-26-2010
20100232837TONER HAVING CORE-SHELL STRUCTURE AND METHOD OF PREPARING THE SAME - A toner has a core-shell structure including a toner core portion having a resin with an active hydrogenactive hydrogen containing group, a colorant and at least one additive, and a toner shell portion surrounding the toner core portion, wherein the toner shell portion includes a cross-linked resin prepared by reaction of at least a portion of the active hydrogen containing group and the cross-linking agent.09-16-2010
20110028643WAX-RESIN COMPATIBILIZER, WAX-RESIN DISPERSION INCLUDING THE WAX-RESIN COMPATIBILIZER, AND METHODS OF PREPARING THE SAME - A wax-resin compatibilizer, a wax-resin dispersion, and methods of preparing the wax-resin dispersion. The wax-resin dispersion includes a wax, the wax-resin compatibilizer, and a second resin. The wax-resin dispersion may have a high wax content and excellent storage stability.02-03-2011
20110076609TONER CONTAINING BINDER RESIN HAVING WAX PROPERTIES AND METHOD OF PREPARING THE TONER - Provided are a toner containing a resin having wax properties and a method of preparing the toner. The toner includes a binder resin into which at least one residue of the group consisting of a C8-C60 higher fatty acid residue and a C8-C60 higher alcohol residue is introduced by esterification, a colorant, and at least one additive.03-31-2011
20110116841TONER HAVING MULTIPLE INFLECTION POINTS ON STORAGE MODULUS CURVE WITH RESPECT TO TEMPERATURE AND METHOD OF PREPARING THE SAME - Provided are a toner and a method of preparing the same. The toner includes a binder resin, a coloring agent, and at least one additive, and a storage modulus curve of the toner with respect to temperature has multiple inflection points. The toner may be used in an electrophotographic image forming apparatus.05-19-2011
20110159424METHOD OF FORMING TONER IMAGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS CAPABLE OF REALIZING WIDE COLOR GAMUT - Provided are a method of forming a toner image and an electrophotographic image forming apparatus including a toner. The method of forming a toner image is performed using a first toner having a yellow color and color coordinate values of a lightness (L) ranging from 91 to 94, a redness (a) ranging from −11 to −9, and a yellowness (b) ranging from 77 to 82; a second toner having a magenta color and color coordinate values of a lightness (L) ranging from 56 to 61, a redness (a) ranging from 56 to 61, and a yellowness (b) ranging from −7 to −5; and a third toner having a cyan color and color coordinate values of a lightness (L) ranging from 58 to 62, a redness (a) ranging from −33 to −30, and a yellowness (b) ranging from −42 to −37.06-30-2011

Hyun Yong Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100040090SYNCHRONIZATION METHOD FOR ALLOWING FIXED TIME DELAY AND BRIDGE EMPLOYING THE SAME - Provided are a time synchronization method allowing a fixed time delay and a bridge that is interposed between a master and a slave, according to the method. In the bridge, a predetermined time after the synchronization packet is set as an output time of the synchronization packet and the synchronization packet is output at the output time. Accordingly, it is possible to delay synchronization packets in the bridge for the same time, thereby increasing the time synchronization precision.02-18-2010

Ii Sun Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100055599METHOD OF PREPARING TONER HAVING CORE-SHELL STRUCTURE AND TONER PREPARED USING THE SAME - A method of preparing a toner having a core-shell structure. The method includes: preparing a mixture by mixing a resin with acid groups, a coloring agent and at least one additive with an organic solvent, and neutralizing the acid groups of the resin with a base; forming a micro-suspension solution by adding the mixture to a dispersion medium; forming a toner core by removing the organic solvent from the micro-suspension; and forming a toner complex having a core-shell structure by seed-polymerizing at least one monomer on the surface of the toner core. Thus, the toner that can prevent hot offsets, improve storage stability at a high temperature and improve charge stability against environment changes can be prepared with reduced costs according to the method.03-04-2010
20100239972TONER USING RESIN HAVING ACTIVE HYDROGEN-CONTAINING GROUP AND METHOD OF PREPARING THE SAME - Provided are a toner using a resin having an active hydrogen-containing group, and a method of preparing the toner. The toner using a resin having an active hydrogen-containing group includes a binder resin (A), a cross-linked resin including a THF insoluble content of 99-100 weight %, a colorant, and at least one additive. The cross-linked resin is arranged in the form of a plurality of islands in each particle of the toner.09-23-2010
20100272471ELECTROPHOTOGRAPHIC TONER AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS USING THE SAME - Provided are an electrophotographic toner and an electrophotographic image forming apparatus using the same. The electrophotographic toner includes: parent toner particles including a binder resin, a colorant, a releasing agent, and a charge control agent; and barium titanate external additives having an average primary particle diameter in the range of about 50 to about 150 nm, an average shape factor (SF1) in the range of about 100 to about 120, a shape factor in the range of about 0.96 to about 1, and an aspect ratio in the range of about 0.89 to about 1, and added to the surface of the parent toner particles.10-28-2010
20110033207TONER USING RESIN BEING INSOLUBLE IN ORGANIC SOLVENTS AND METHOD FOR PREPARING THE SAME - A toner using an organic solvent-insoluble resin and a method of preparing the same. The toner includes: a binder resin that comprises an organic solvent-insoluble resin and an acid group-containing resin, a coloring agent, and at least one additive, wherein the organic solvent-insoluble resin is a crosslinked polyester resin or a cyclic olefin co-polymer (COC) resin, and the ratio of the organic solvent-insoluble resin to the acid group-containing resin is in the range of 5:95 to 40:60 on a weight basis. The toner can be applied to an electrophotographic imaging apparatus.02-10-2011

Il Sun Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100098462METHOD OF PREPARING TONER USING MICRO-SUSPENSION PARTICLES AND TONER PREPARED USING THE METHOD DIGITAL IMAGE DATA - A method of preparing a toner using a micro-suspension particle, includes preparing a mixture by mixing a resin having acidic groups, a master batch of coloring pigment, and at least one additive with an organic solvent, and then neutralizing the acid groups of the resin with a base; forming a micro-suspension by adding the prepared mixture to a dispersion medium; and forming a toner composition by removing the organic solvent from the prepared micro-suspension. Therefore, the method of preparing a toner using the disclosed micro-suspension particle and a toner prepared using the same can save manufacturing costs, and can improve charging ability and cleaning properties of the toner.04-22-2010
20100216069METHOD OF PREPARING TONER - Provided is a method of preparing a toner, the method including: preparing a solvent emulsion by stirring a medium including a polar medium, an organic solvent, and a surfactant; adding toner components including a resin and a pigment to the solvent emulsion; removing the organic solvent from the solvent emulsion including the toner components; and collecting a toner particle from the solvent emulsion from which the organic solvent is removed.08-26-2010
20100232837TONER HAVING CORE-SHELL STRUCTURE AND METHOD OF PREPARING THE SAME - A toner has a core-shell structure including a toner core portion having a resin with an active hydrogenactive hydrogen containing group, a colorant and at least one additive, and a toner shell portion surrounding the toner core portion, wherein the toner shell portion includes a cross-linked resin prepared by reaction of at least a portion of the active hydrogen containing group and the cross-linking agent.09-16-2010
20110028643WAX-RESIN COMPATIBILIZER, WAX-RESIN DISPERSION INCLUDING THE WAX-RESIN COMPATIBILIZER, AND METHODS OF PREPARING THE SAME - A wax-resin compatibilizer, a wax-resin dispersion, and methods of preparing the wax-resin dispersion. The wax-resin dispersion includes a wax, the wax-resin compatibilizer, and a second resin. The wax-resin dispersion may have a high wax content and excellent storage stability.02-03-2011
20110076609TONER CONTAINING BINDER RESIN HAVING WAX PROPERTIES AND METHOD OF PREPARING THE TONER - Provided are a toner containing a resin having wax properties and a method of preparing the toner. The toner includes a binder resin into which at least one residue of the group consisting of a C8-C60 higher fatty acid residue and a C8-C60 higher alcohol residue is introduced by esterification, a colorant, and at least one additive.03-31-2011
20110116841TONER HAVING MULTIPLE INFLECTION POINTS ON STORAGE MODULUS CURVE WITH RESPECT TO TEMPERATURE AND METHOD OF PREPARING THE SAME - Provided are a toner and a method of preparing the same. The toner includes a binder resin, a coloring agent, and at least one additive, and a storage modulus curve of the toner with respect to temperature has multiple inflection points. The toner may be used in an electrophotographic image forming apparatus.05-19-2011
20110159424METHOD OF FORMING TONER IMAGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS CAPABLE OF REALIZING WIDE COLOR GAMUT - Provided are a method of forming a toner image and an electrophotographic image forming apparatus including a toner. The method of forming a toner image is performed using a first toner having a yellow color and color coordinate values of a lightness (L) ranging from 91 to 94, a redness (a) ranging from −11 to −9, and a yellowness (b) ranging from 77 to 82; a second toner having a magenta color and color coordinate values of a lightness (L) ranging from 56 to 61, a redness (a) ranging from 56 to 61, and a yellowness (b) ranging from −7 to −5; and a third toner having a cyan color and color coordinate values of a lightness (L) ranging from 58 to 62, a redness (a) ranging from −33 to −30, and a yellowness (b) ranging from −42 to −37.06-30-2011

In-Ki Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100262728DIRECT MEMORY ACCESS CONTROLLER FOR IMPROVING DATA TRANSMISSION EFFICIENCY IN MMoIP AND METHOD THEREFOR - A direct memory access controller (DMAC) for improving data transmission efficiency in multi-media over internet protocol (MMoIP) and a method therefor are provided. The DMAC requests and obtains a bus control right by determining that a DMA request signal is generated not only when a DMA request signal of a module for processing data in MMoIP is received but also when an operation of a timer operating during a predetermined period set considering periodicity of data in MMoIP is completed. Thus, the time taken to request a bus control right in a conventional DMAC can be reduced, thereby improving data transmission efficiency in MMoIP.10-14-2010

Jae Kwang Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100055599METHOD OF PREPARING TONER HAVING CORE-SHELL STRUCTURE AND TONER PREPARED USING THE SAME - A method of preparing a toner having a core-shell structure. The method includes: preparing a mixture by mixing a resin with acid groups, a coloring agent and at least one additive with an organic solvent, and neutralizing the acid groups of the resin with a base; forming a micro-suspension solution by adding the mixture to a dispersion medium; forming a toner core by removing the organic solvent from the micro-suspension; and forming a toner complex having a core-shell structure by seed-polymerizing at least one monomer on the surface of the toner core. Thus, the toner that can prevent hot offsets, improve storage stability at a high temperature and improve charge stability against environment changes can be prepared with reduced costs according to the method.03-04-2010
20100098462METHOD OF PREPARING TONER USING MICRO-SUSPENSION PARTICLES AND TONER PREPARED USING THE METHOD DIGITAL IMAGE DATA - A method of preparing a toner using a micro-suspension particle, includes preparing a mixture by mixing a resin having acidic groups, a master batch of coloring pigment, and at least one additive with an organic solvent, and then neutralizing the acid groups of the resin with a base; forming a micro-suspension by adding the prepared mixture to a dispersion medium; and forming a toner composition by removing the organic solvent from the prepared micro-suspension. Therefore, the method of preparing a toner using the disclosed micro-suspension particle and a toner prepared using the same can save manufacturing costs, and can improve charging ability and cleaning properties of the toner.04-22-2010
20100216069METHOD OF PREPARING TONER - Provided is a method of preparing a toner, the method including: preparing a solvent emulsion by stirring a medium including a polar medium, an organic solvent, and a surfactant; adding toner components including a resin and a pigment to the solvent emulsion; removing the organic solvent from the solvent emulsion including the toner components; and collecting a toner particle from the solvent emulsion from which the organic solvent is removed.08-26-2010
20100232837TONER HAVING CORE-SHELL STRUCTURE AND METHOD OF PREPARING THE SAME - A toner has a core-shell structure including a toner core portion having a resin with an active hydrogenactive hydrogen containing group, a colorant and at least one additive, and a toner shell portion surrounding the toner core portion, wherein the toner shell portion includes a cross-linked resin prepared by reaction of at least a portion of the active hydrogen containing group and the cross-linking agent.09-16-2010
20100239972TONER USING RESIN HAVING ACTIVE HYDROGEN-CONTAINING GROUP AND METHOD OF PREPARING THE SAME - Provided are a toner using a resin having an active hydrogen-containing group, and a method of preparing the toner. The toner using a resin having an active hydrogen-containing group includes a binder resin (A), a cross-linked resin including a THF insoluble content of 99-100 weight %, a colorant, and at least one additive. The cross-linked resin is arranged in the form of a plurality of islands in each particle of the toner.09-23-2010
20100272471ELECTROPHOTOGRAPHIC TONER AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS USING THE SAME - Provided are an electrophotographic toner and an electrophotographic image forming apparatus using the same. The electrophotographic toner includes: parent toner particles including a binder resin, a colorant, a releasing agent, and a charge control agent; and barium titanate external additives having an average primary particle diameter in the range of about 50 to about 150 nm, an average shape factor (SF1) in the range of about 100 to about 120, a shape factor in the range of about 0.96 to about 1, and an aspect ratio in the range of about 0.89 to about 1, and added to the surface of the parent toner particles.10-28-2010
20110033207TONER USING RESIN BEING INSOLUBLE IN ORGANIC SOLVENTS AND METHOD FOR PREPARING THE SAME - A toner using an organic solvent-insoluble resin and a method of preparing the same. The toner includes: a binder resin that comprises an organic solvent-insoluble resin and an acid group-containing resin, a coloring agent, and at least one additive, wherein the organic solvent-insoluble resin is a crosslinked polyester resin or a cyclic olefin co-polymer (COC) resin, and the ratio of the organic solvent-insoluble resin to the acid group-containing resin is in the range of 5:95 to 40:60 on a weight basis. The toner can be applied to an electrophotographic imaging apparatus.02-10-2011
20110116841TONER HAVING MULTIPLE INFLECTION POINTS ON STORAGE MODULUS CURVE WITH RESPECT TO TEMPERATURE AND METHOD OF PREPARING THE SAME - Provided are a toner and a method of preparing the same. The toner includes a binder resin, a coloring agent, and at least one additive, and a storage modulus curve of the toner with respect to temperature has multiple inflection points. The toner may be used in an electrophotographic image forming apparatus.05-19-2011
20110159424METHOD OF FORMING TONER IMAGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS CAPABLE OF REALIZING WIDE COLOR GAMUT - Provided are a method of forming a toner image and an electrophotographic image forming apparatus including a toner. The method of forming a toner image is performed using a first toner having a yellow color and color coordinate values of a lightness (L) ranging from 91 to 94, a redness (a) ranging from −11 to −9, and a yellowness (b) ranging from 77 to 82; a second toner having a magenta color and color coordinate values of a lightness (L) ranging from 56 to 61, a redness (a) ranging from 56 to 61, and a yellowness (b) ranging from −7 to −5; and a third toner having a cyan color and color coordinate values of a lightness (L) ranging from 58 to 62, a redness (a) ranging from −33 to −30, and a yellowness (b) ranging from −42 to −37.06-30-2011

Jung-Hwan Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20080259827Communication System Using Frequency According to Security or Transmission Distance - A communication system using a frequency determined according to information security protection or a transmission distance of a signal is provided. A local area communication requiring information security protection uses a frequency less than a predetermined frequency, and a local or wide area communication requiring no information security protection uses a frequency greater than predetermined frequency, thereby providing an effective communication environment based on information security protection, a communication distance, and communication characteristics satisfying frequency characteristics of a transmission medium, and accordingly increasing a communication field.10-23-2008
20080294722Method and Apparatus for Providing Touch and Play (Tap) - Based Service and System Using the Method and Apparatus - Provided are a method, apparatus and system for providing a touch and play (TAP)-based service. The method includes setting respective device identifiers of a plurality of devices which can be connected to a device using an organism as a transmission channel and setting services to be provided to a user through the interaction between the device and each of the devices corresponding to the device identifiers, respectively; having at least two execution levels so that one of the at least two execution levels can be selected in order to determine whether to execute a service in cooperation with one of the devices and setting one of the at least two execution levels according to an input from a user; receiving a device identifier of another device if the device is connected to one of the devices using the organism as the transmission channel; recognizing services set for the other device and identifying a service that is to be provided to the user through the interaction between the device and the other device; determining whether to execute the identified service according to the set execution level; and automatically recognizing information required to provide the service that is determined to be executed in cooperation with the other device and executing the determined service. When the method, apparatus and the system are used, a user can receive a desired service by simply touching two devices.11-27-2008
20090103643HUMAN BODY COMMUNICATION METHOD USING MULTI-CARRIER MODULATION METHOD - Provided is a human body communication method using a multi-carrier modulation method, in which users do not interfere with each other in an environment with several users, and stable communication is possible when users are exposed to strong interference generated at other electronic devices. Also, provided are a multi-carrier modulation method, in which data between communication devices connected to a human body used as a channel is divided into a plurality of sub-channels and the data is transmitted by loading it on each of a plurality of sub-carrier signals, and a multi-connection method using the multi-carrier modulation method. The plurality of sub-channels having a predetermined bandwidth include several sub-carriers, and by changing a modulation method applied to the sub-carriers, stable communication can be realized.04-23-2009
20090233558COMMUNICATION DEVICE AND METHOD USING HUMAN BODY - A communication device and method using the human body are provided. The communication device determines an arrangement direction of signal electrodes and ground electrodes according to a signal transmission direction and whether the ground electrodes come into contact with the human body according to a transmission/receiving distance and then performs data communication with the other communication device connected to the human body for the purpose of efficient human body communication.09-17-2009
20100172394METHOD OF AND APPARATUS FOR TRANSMITTING AND RECEIVING SIGNAL AT VARIABLE DATA RATE IN HUMAN BODY COMMUNICATIONS - Provided are a method and apparatus for transmitting and receiving a signal at a variable data rate in human body communications. The apparatus includes a header generator, a data generator, a spreader, and a multiplexer. The header generator generates header information including a data rate. The data generator generates transmission data by repeating each data bit to be transmitted 0 to several times according to the data rate. The spreader spreads the transmission data using a spreading code in a desired frequency band. The multiplexer multiplexes the header information and the spread data.07-08-2010
20100238955METHOD AND DEVICE FOR COMMUNICATING USING HUMAN BODY - A communication device and method is provided. The communication method using a human body includes modulating data, generating a first timing signal by using the modulated data, generating a wideband pulse with a short time interval on the basis of the first timing signal, and transmitting the wideband pulse through an electrode unit that contacts a human body.09-23-2010
20100322294HUMAN BODY COMMUNICATION DEVICE, HUMAN BODY COMMUNICATION SYSTEM AND METHOD USING THE SAME - A human body communication apparatus, a human body communication system, and a method using the same are provided. The communication apparatus is directly in contact with a human body and allows a small amount of current including a data signal to flow through the body so that information is communicated through the human body.12-23-2010

Patent applications by Jung-Hwan Hwang, Daejeon-City KR

Jun Hwan Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20080284607Communication Apparatus Having Human Body Contact Sensing Function and Method Thereof - Provided is a communication apparatus having a human body contact sensing function and a method thereof. The communication apparatus includes: an electrode that comes in contact with the human body; a contact sensor that is connected to the electrode, and instructs the central processing unit to perform an initial operation if contact with the human body is sensed; and a data processing unit that receives a control signal from the central processing unit so as to select whether to transmit or receive data, and performs a transmitting or receiving operation according to the control signal. Accordingly, in order to reduce power consumption when in a stand-by state before human body contact is made in a communication apparatus using a human body as a communication medium, a human body contact sensor is included so as to minimize power consumption of a micro processing unit and a transmitter/receiver circuit until contact occurs. Therefore, since power consumption is minimized when in a stand-by mode by using a contact sensor having significantly low power consumption, there is an advantage in that a stand-by time of a portable device is extended.11-20-2008

Kyu-Jong Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20110059700ADAPTIVE TRANSMISSION AND RECEIVING METHOD AND DEVICE IN WIRELESS COMMUNICATION SYSTEM WITH MULTIPLE ANTENNAS - Disclosed is an adaptive transmit and receive method and device in a multiple-antenna wireless communication system. A transmit mode comprises different main transmit modes each of which includes one or both of a sub-transmit mode based on STBC and a sub-transmit mode based on SM. A receiver calculates an STBC performance parameter and a SM performance parameter, and a transmitter uses the parameters to determine a main transmit mode with maximum data rates and select a sub-transmit mode for minimizing power consumption. The transmitter channel-encodes, modulates and antenna-maps input data according to the selected transmit mode, and outputs results to the receiver. The receiver antenna/symbol-demodulates and channel-decodes the received data.03-10-2011

Yoola Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20100090889PRECISE ORBIT DETERMINATION SYSTEM AND METHOD USING GPS DATA AND GALILEO DATA - Provided are a method and system for determining a precise orbit of a LEO satellite. The method includes: estimating a precise ephemeris of a global positioning system (GPS) satellite by fitting an orbit perturbation-based GPS dynamics model to observation data of the GPS satellite received from a GPS observatory and estimating a precise ephemeris of a Galileo satellite by fitting an orbit perturbation-based Galileo dynamics model to observation data of the Galileo satellite received from a Galileo observatory; determining an initial orbit value of a LEO satellite by fitting an orbit perturbation-based LEO satellite's basic dynamics model to navigation data received from the LEO satellite; and determining the precise orbit of the LEO satellite by calculating a difference between observation values, which are calculated based on a GPS and Galileo data received from the LEO satellite, the GPS observatory and the Galileo observatory, and calculated values, which are calculated based on an orbit perturbation-based LEO satellite's dynamics model that was calculated using the initial orbit value of the LEO satellite and the precise ephemeris of the GPS and Galileo satellites. Since both the GPS and Galileo data are received and used to determine the precise orbit of a LEO satellite, more precise orbit determination can be achieved.04-15-2010

Young Ju Hwang, Daejeon-City KR

Patent application numberDescriptionPublished
20090141667METHOD FOR ROUTING MESSAGE IN WIRELESS NETWORK BASED ON RELAY PROBABILITY - Provided is a method for routing a message in a wireless network based on relay probability. The method allows dynamic delivery of a message by calculating the relay probability of each node for message transmission, measuring the strength of a beacon signal received from a destination node, and determining a node that will relay a message based on the relay probability and the strength of beacon signal.06-04-2009