Abstract: Provided are modulation and demodulation methods and apparatuses using a frequency selective baseband. The frequency modulation method includes: generating a plurality of subgroups by dividing 2N (N is a real number) spread codes used for frequency spreading into 2M (M<N, M is a real number) spread codes; selecting P(P is a real number) subgroups among the generated subgroups; acquiring P spread codes by inputting M data bits to each of the p subgroups so as for 1 spread code to be selected among the 2M spread codes of each subgroup; and selecting dominant value among the acquired P spread codes to generate transmitting data including the dominant value. Accordingly, it is possible to increase a processing gain of the entire system, to increase a transmission data rate, and to reduce power consumption of the system.

Abstract: Provided are symbol-error-correctable modulation and demodulation methods and apparatuses using a frequency selective baseband.

Abstract: A Time Division Duplex (TDD) communication apparatus and an operation method thereof can provide operation clock signals in the transmission and reception of the TDD communication apparatus using a Clock Recovery & Data Retiming (CDR) circuit, thereby stabilizing an operation without any crystal oscillator and reducing the power consumption. In a transmission time interval, a transmitting frame is processed using a clock signal of a reference frequency generated from the CDR circuit. In a reception time interval, a receiving frame is processed using a clock signal recovered from the receiving frame by the CDR circuit.

Abstract: Provided is a suspended nanowire sensor having good sensing characteristics and suitable for mass production, a method for fabricating the suspended nanowire sensor. The suspended nanowire sensor includes: first and second sensor electrodes formed on upper portions of a substrate and physically separated from each other; and a nanowire sensor material piece extending from the first sensor electrode to the second sensor electrode and physically suspended between the first and second sensor electrodes.

Abstract: Provided are a frequency modulation/demodulation apparatus using a frequency selective baseband and a transmitting/receiving apparatus using the same. In a frequency selective baseband transmission technique or an FS-CDMA technique, a transmission rate is controlled according to communication channel environment, spread code groups are repeatedly selected in a receiving side so as to obtain a frequency diversity gain. Accordingly, it is possible to reduce interference between users. In addition, even in a case where strong interference induced from electronic exists, it is possible to implement low-power, stable human-body communication and to ensure a communication quality.

Abstract: 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. In order to efficiently perform a data communication by preventing a collision of data packets in the human body communication system, one communication apparatus is selected from a plurality of communication apparatuses configuring the human body communication system to control or manage a communication order for other communication apparatuses and the respective apparatuses check whether the respective communication apparatuses transmit data through the human body to try a communication.

Abstract: There is provided an apparatus for providing a media advertisement service using human body communication, including: conductive contact part for contact with a human body; a control part configured to detect human body contact of a user with the conductive contact part and acquire user-contact-associated contents, the user-contact-associated-contents being contents associated with an advertisement selected by the human body contact of the user; and a human body communication part configured to convert the acquired user-contact-associated contents into a signal for human body communication and send the signal to a user terminal via the conductive contact part and a user's body.

Abstract: A detection apparatus for an eddy current in a heat generating tube using a permeability measurement method, and a method using the apparatus are provided. In the detection apparatus, a bobbin type probe acquires detection information with respect to a magnetic flux change by a magnetic phase occurring in the heat generating tube using a coil which is wound in an axis direction of at least one yoke located in a perpendicular direction with a bobbin of the bobbin type probe, and a material having a corresponding magnetic phase and a circumferential defect, which is difficult to be detected by the bobbin type probe, are detected based on the detection information.

Abstract: A human body communication system is provided. The human body communication system includes a transmitter and a receiver. The transmitter transmits a frame including a preamble, which is a Manchester-encoded pseudo noise (PN) code, to the human body. The receiver receives the frame from the human body, performs Manchester-decoding on the frame, performs cross-correlation on the decoding result and the PN code, and performs frame synchronization using the cross-correlation result. Accordingly, clock and data recovery performance is improved. Efficient frame synchronization with reduced computation amount can be provided.

Abstract: Provided are a system and method for human body communication using a limited passband. The system includes a transmission frame generating unit for human body communication which generates a transmission frame for human body communication based on data information including user identification (ID) and data scrambled into an orthogonal code generated by the user ID; a symbol mapping unit for symbolizing the generated transmission frame for human body communication according to a predetermined modulating method; a spreading unit for spreading the symbol outputted in the symbol mapping unit; a waveform generating unit for generating a baseband signal whose band is limited to a predetermined range with respect to the data spread in the spreading unit; and a middle band transmitting unit for modulating the baseband signal into a predetermined limited passband signal.

Abstract: 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.

Abstract: There is provided a human body communication apparatus capable of performing communications through the contact with external devices (a central processing unit) and a human body. The human body communication apparatus includes a plurality of contact sensor units including a plurality of electrode contacted with a human body and having conductivity, and a plurality of electrostatic sensor units coupled to the electrodes to sense an electrostatic capacity changed through the contact with the human body and generate a contact signal using the sensed electrostatic capacity; a signal analyzer unit for analyzing the contact signal received from the contact sensor units; and a control signal generator unit for generating a control signal as the analysis result in the signal analyzer unit.

Abstract: A method and apparatus for communicating a sound wave is provided. The apparatus includes: a sound wave converter converting a sound wave signal transmitted from a counter apparatus through the human body into an electrical signal when the sound wave is transmitted from the counter apparatus through the human body and converting an electrical signal on data to be output to the counter apparatus into a sound wave; a data processor receiving the converted electrical signal from the sound wave converter and transmitting an electrical signal on the data to be output to the sound wave converter when the data to be output exists; and a switch connected between the sound wave converter and the data processor, the switch transmitting the converted electrical signal to the data processor and transmitting the electrical signal on the data to be output to the sound wave converter. Accordingly, it is possible to efficiently transmit a signal with a low loss of sound wave signal.

Abstract: Provided are modulation and demodulation methods and apparatuses using a frequency selective baseband. The frequency modulation method includes: generating a plurality of subgroups by dividing 2N (N is a real number) spread codes used for frequency spreading into 2M (M<N, M is a real number) spread codes; selecting P(P is a real number) subgroups among the generated subgroups; acquiring P spread codes by inputting M data bits to each of the p subgroups so as for 1 spread code to be selected among the 2M spread codes of each subgroup; and selecting dominant value among the acquired P spread codes to generate transmitting data including the dominant value. Accordingly, it is possible to increase a processing gain of the entire system, to increase a transmission data rate, and to reduce power consumption of the system.

Abstract: 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.

Abstract: Provided are an apparatus and a method for controlling human body contact of ground electrode, and a human body communication system using the same. The apparatus includes a resistance measuring unit for applying a predetermined voltage to a human body through a signal electrode, to measure a resistance value between the signal electrode and the ground electrode; a contact control unit for determining whether the ground electrode needs to contact the human body by using the measured resistance value, to provide control information associated with human body contact; and a contact performing unit for bringing the ground electrode into contact or out of contact with the human body according to the control information.

Abstract: Provided are a human body sound transmission system and a method using single sound source. The human body sound transmission system includes a first transmission block for transmitting a combined signal of a first high frequency signal and a sound signal through a human body; and a second transmission block for transmitting a second high frequency signal having the same frequency as the first high frequency signal through the human body, to thereby recover the sound signal by destructing interference in a ear region of a user.

Abstract: Provided are an apparatus for transmitting reference signals for measuring the phase response characteristic of a human body in human body communication, and a system and method for measuring the phase response characteristic of a human body using the same. The apparatus including: a signal generator for generating reference signals for measuring the phase response characteristic of a human body; a signal distributor for distributing the generated reference signals to a transmitting electrode and a frequency converter; the transmitting electrode for applying the reference signals distributed by the signal distributor to a human body; the frequency converter for converting the frequency of the reference signals distributed by the signal distributor into a frequency different from a frequency of a reference signal applied to the human body via the transmitting electrode; and a radio antenna for wirelessly transmitting the frequency-converted reference signal to a free space.

Abstract: Provided are a DMB receiving portable apparatus for human body communication, a DMB transmitting method thereof, and an HMD apparatus and method for DMB reception using human body communication. The digital multimedia broadcasting (DMB) receiving portable apparatus for human body communication includes: a DMB receiver adapted to perform DMB Rx signal processing on a DMB signal to convert the DMB signal into an audio/video signal, and transmit to a transmission electrode an intermediate frequency (IF) band broadcast signal or a transmission stream (TS) generated in the DMB Rx signal processing; and the transmission electrode adapted to apply the IF band broadcast signal or the TS to the human body as a DMB signal for human body communication.

Abstract: Provided is an intra-body communication system which enables high-speed data transmission while limiting the frequency band of a signal being transmitted through a human body to a frequency range (e.g., 30-40 MHz) where the human body can maintain waveguide properties and enables stable intra-body communication by minimizing interference by other users or other electronic devices. A transceiver of the intra-body communication system for high-speed data transmission includes: a source encoder for encoding source information to digital transmission data; a channel error prevention unit for inserting a redundant bit to the encoded transmission data; a mapper for symbolizing the transmission data outputted from the channel error prevention unit; a spreader for performing spread spectrum on the symbolized transmission data in a frequency domain; and a pulse shaping and modulator for generating a baseband signal with a band range limited to a frequency range where the human body retains waveguide properties.