摘要:
A frequency selective modulation apparatus and method using re-spreading codes are disclosed. The frequency selective modulation apparatus includes: a serial-to-parallel converter receiving transmission data and performing serial-to-parallel conversion on the transmission data at a pre-set ratio; one or more sub-frequency selective spreaders selecting one spreading code by using data bits received from the serial-to-parallel converter; a majority value selection unit selecting a majority value from one or more spreading codes which have been selected by each of the one or more of the sub-frequency selective spreaders; and a first XOR logic circuit XORing an output of the majority value selection unit and a re-spreading code Wn to re-spread a frequency selective baseband to a frequency selective passband.
摘要:
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. Thus, it is possible to simply construct communication hardware at a low price.
摘要:
A communication apparatus using a synchronized clock signal includes: a communication signal generation unit generating one of a baseband signal and a signal obtained by applying digital modulation to the baseband signal, as a communication signal; an interface unit transmitting the generated communication signal and receiving a communication signal from an external source; a communication signal analyzing unit analyzing the received communication signal; a clock signal providing unit providing a clock signal to the communication signal generation unit, the interface unit, and the communication signal analyzing unit; and a controller controlling the communication signal generation unit, the interface unit, the communication signal analyzing unit, and the clock signal providing unit.
摘要:
Provided is a method of generating and detecting a preamble that may significantly increase accuracy of frame synchronization while avoiding a low frequency domain having great noise power and minimizing hardware complexity and power consumption in a communication system of a digital direct transmission scheme applicable to human body communication. A method of generating a preamble according to an exemplary embodiment of the present disclosure includes: generating a first pseudo noise code and a second pseudo noise code that are different from each other; generating a plurality of same first sub preambles by line-coding the first pseudo noise code; and generating a second sub preamble behind the plurality of first sub preambles by line-coding the second pseudo noise code.
摘要:
An adaptive frequency selective baseband communications method using orthogonal codes includes: a communications testing step of performing communications by using one of a plurality of codes each having a different frequency band; a proper code selecting step of selecting a proper code by using a correlation value of a plurality of codes included in test data transmitted in the communications testing step; a communications performing step of performing communications by using the proper code; and a feedback step of newly selecting a proper code by using the correlation value of the plurality of codes included in the test data transmitted in the communications performing step if a pre-set time duration has lapsed or if a reception error of more than a pre-set reference occurs, and performing the communications performing step again, wherein the test data transmitted in the communications testing step and the communications performing step includes a plurality of codes each having a different frequency band.
摘要:
Provided is an apparatus and method for transmitting a multi millimeter wave, which can minimize signal interference and crosstalk between devices using millimeter waves as transmission frequencies. The apparatus includes a scanner, a physical layer controller and a physical layer. The scanner searches for a peripheral communication environment. The physical layer controller selects a transmission mode from the physical layer based on the peripheral communication environment searched by the scanner. The physical layer has a plurality of transmission modes and outputs a millimeter wave to an outside through an antenna in the transmission mode selected under a control of the physical layer controller.
摘要:
There are provided a receiver in human body communication system using multiple receivers capable of reducing an error rate of receiver signals by applying a space diversity acquisition-related SIMO technology to a plurality of received data using multiple receivers or receiver electrodes in a human body communication system using a human body as a medium, and of stably transmitting the data for the interference of signals generated by other users or from different electronic devices, and a method for receiving data in a human body communication system. The receiver and the method for receiving data in a human body communication system may be useful to stably transmit/receive data without any reduction of its transmission rate by reducing the distortion in channels and the signal noise which are caused in the use of one receiver.
摘要:
Disclosed is a system for providing multimedia data using human body communication in transportation capable of improving user convenience in transportation and providing various multimedia data. The system for providing multimedia data using human body communication in transportation includes: a multimedia data providing device converting multimedia data into a signal available for human communication and transmitting the converted signal to one or more of conductive units installed within transportation; and a human body communication device receiving the multimedia data through a user's body brought into contact with the one or more conductive units and executing the received multimedia data.
摘要:
A method for generating a communication frame of a body area network, includes: recognizing the number of terminals existing within a predetermined area; allocating an individual frame to be used by each of the terminals existing within the predetermined area according to the recognized number of terminals; and allocating a coexistence frame to be transmitted to every terminal existing within the predetermined area according to the recognized number of terminals.
摘要:
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.