Abstract: A mobile terminal communicates with a base station to request channel allocation for RFID communication, receives a channel from the base station, and communicates with an RFID tag through the allocated channel.

Abstract: A radio frequency identification (RFID) recorder for cancelling a leakage signal includes a digital unit calculating and storing an amplitude and a phase of the leakage signal, and a leakage cancellation circuit generating a leakage cancellation signal to cancel the leakage signal in response to a control of the digital unit.

Abstract: A Radio Frequency (RF) transmission method of a Radio Frequency Identification (RFID) reader using a plurality of channels is provided. The method includes: selecting at least part of the plurality of channels, measuring an RF power of each of the selected channels, determining a transmission environment of the RF according to a measurement determination, and modulating an RF signal according to the determined transmission environment.

Abstract: A mobile radio frequency identification (mRFID) reader having a receiving circuit is provided. The receiving circuit includes a local oscillator which generates a carrier signal at a predetermined frequency band; a mixer which mixes a tag signal received from a tag with the carrier signal, to lower a frequency of the tag signal; a phase adjusting block which adjusts a phase of the carrier signal by determining a phase of the tag signal; and a control block which processes the tag signal through a series of operations, and controls an operation of the phase adjusting block to compensate for a phase delay of the tag signal according to an output of the processed tag signal. Because the mRFID reader can be provided as small as a half size of a related art reader, a mobile communication terminal accommodating the mRFID reader can be compact-sized. Additionally, because the number of components for the receiving circuit decreases, not only the power consumption but also the unit price can be reduced.

Abstract: A wireless terminal and a radio frequency identification system for providing additional information and a method of providing additional information using the wireless terminal and the radio frequency identification system. The wireless terminal includes: a tag reader reading tag data from a radio frequency identification tag; a controller generating an additional information request signal with respect to the read tag data; and a communication network interface transmitting the additional information request signal through a communication network and receiving additional information with respect to the additional information request signal. Since the controller of the wireless terminal controls the radio frequency identification reader by optimally setting the information required for determining the time point for the radio frequency identification reader tag to respond, and utilizing the stored address of the additional information providing server, the additional information can be efficiently provided.

Abstract: Disclosed is a correlation method to adaptively operate in a time varying phase and a correlator thereof. A correlation method according to the present invention includes performing the first correlation according to a certain reference value and a certain reference interval for correlation of a received signal; calculating an average variation of the received signal through the result of performing the first correlation; deciding a new reference value for the second correlation through the average variation; performing the second correlation according to the new reference value and the reference interval; and selecting the maximum value among the result of performing the second correlation. Accordingly, plural references are decided considering variation of a response signal between tags and also separate plural references are decided considering bit variation of a response signal in the same tag, so that a digital signal can be ideally demodulated in the environment where signal phase variation occurs.

Abstract: A method and system for avoiding tag conflict by identifying a RFID using a K-nary tree search. The tag conflict avoidance system includes a plurality of tags receiving a first signal, converting identification codes of the tags into predetermined codes according to the first signal, and outputting the converted codes as second signals. The tag conflict avoidance system also includes a reader outputting the first signal, receiving the second signals, and identifying the tags using the codes included in the second signals.

Abstract: A mobile terminal communicates with a base station to request channel allocation for RFID communication, receives a channel from the base station, and communicates with an RFID tag through the allocated channel.

Abstract: A Radio Frequency (RF) transmission method of a Radio Frequency Identification (RFID) reader using a plurality of channels is provided. The method includes: selecting at least part of the plurality of channels, measuring an RF power of each of the selected channels, determining a transmission environment of the RF according to a measurement determination, and modulating an RF signal according to the determined transmission environment.

Abstract: A radio frequency identification (RFID) reader includes a transmitter generating a transmission signal for transmission to a tag, a receiver receiving a response signal from the tag, a leakage compensator compensating a leakage signal leaked from the transmitter to the receiver in response to a leakage control signal, and a control unit performing a leakage test operation by applying a test signal to the transmitter, and calculating and storing a leakage parameter for generating the leakage control signal using a level difference of the test signal and a level difference of a test leakage signal leaked to the receiver.

Abstract: A radio frequency identification (RFID) recorder for cancelling a leakage signal includes a digital unit calculating and storing an amplitude and a phase of the leakage signal, and a leakage cancellation circuit generating a leakage cancellation signal to cancel the leakage signal in response to a control of the digital unit.

Abstract: A location tracking system and method are provided. The location tracking system includes a plurality of tags which receive a read signal and which output tag signals, a reader which transmits the read signal to the tags, receives the tag signals, and identifies tag IDs from the tag signals, and a data processing system which stores location information of the tags and determines the location of the reader by using the tag IDs received from the reader based on the location information.

Abstract: A mobile radio frequency identification (mRFID) reader having a receiving circuit is provided. The receiving circuit includes a local oscillator which generates a carrier signal at a predetermined frequency band; a mixer which mixes a tag signal received from a tag with the carrier signal, to lower a frequency of the tag signal; a phase adjusting block which adjusts a phase of the carrier signal by determining a phase of the tag signal; and a control block which processes the tag signal through a series of operations, and controls an operation of the phase adjusting block to compensate for a phase delay of the tag signal according to an output of the processed tag signal. Because the mRFID reader can be provided as small as a half size of a related art reader, a mobile communication terminal accommodating the mRFID reader can be compact-sized. Additionally, because the number of components for the receiving circuit decreases, not only the power consumption but also the unit price can be reduced.

Abstract: A system and method for providing geographical information to a driver of a vehicle using radio frequency identification (RFID). Also provided is a traffic information supply system using RFID. The geographical information supply system includes a reader provided near a road which outputs a first signal and receives a second signal generated in response to the first signal; a tag that senses the first signal, converts information on a destination into the second signal in response to the first signal, and outputs the second signal. Also included is a first control unit which extracts and outputs the destination information from the second signal, receives geographical information to the destination, and supplies the geographical information to a driver. A server generates the geographical information corresponding to the destination information and outputs the generated geographical information to the first control unit.

Abstract: Disclosed is a correlation method to adaptively operate in a time varying phase and a correlator thereof. A correlation method according to the present invention includes performing the first correlation according to a certain reference value and a certain reference interval for correlation of a received signal; calculating an average variation of the received signal through the result of performing the first correlation; deciding a new reference value for the second correlation through the average variation; performing the second correlation according to the new reference value and the reference interval; and selecting the maximum value among the result of performing the second correlation. Accordingly, plural references are decided considering variation of a response signal between tags and also separate plural references are decided considering bit variation of a response signal in the same tag, so that a digital signal can be ideally demodulated in the environment where signal phase variation occurs.

Abstract: A radio frequency identification (RFID) tag and a RFID reader for anti-collision, and an operation method thereof are provided. The RFID tag includes a tag receiving part for receiving a tag recognition signal from a RFID reader, a tag transmitting part for transmitting a response signal and a tag data in response to the tag recognition signal, a mode switching part for switching current mode into a predetermined mode, and a controlling part for causing the predetermined mode to be switched by the mode switching part, when the response signal is transmitted by a predetermined number of times by the tag transmitting part. Accordingly, when a few number of RFID tags are used, collision of tag data can be prevented at the RFID reader, and the RFID tags are rapidly recognized.

Abstract: A wireless terminal and a radio frequency identification system for providing additional information and a method of providing additional information using the wireless terminal and the radio frequency identification system. The wireless terminal includes: a tag reader reading tag data from a radio frequency identification tag; a controller generating an additional information request signal with respect to the read tag data; and a communication network interface transmitting the additional information request signal through a communication network and receiving additional information with respect to the additional information request signal. Since the controller of the wireless terminal controls the radio frequency identification reader by optimally setting the information required for determining the time point for the radio frequency identification reader tag to respond, and utilizing the stored address of the additional information providing server, the additional information can be efficiently provided.

Abstract: Content playback systems and methods, in which a desired content file can be easily played back in real time using radio frequency identification, are provided. The content playback system includes one or more tags, a playback unit, and a reader. The tags store one or more content files. The playback unit plays back a selected content file. The reader reads the selected content file, which is stored in one of the tags, in a non-contact manner and transmits the read content file to the playback unit.

Abstract: A tag conflict avoidance method and system are provided. The tag conflict avoidance system includes a plurality of tags receiving a first signal, converting identification codes of the tags into predetermined codes according to the first signal, and outputting the converted codes as second signals; and a reader outputting the first signal, receiving the second signals, and identifying the tags using the codes included in the second signals.

Abstract: A location tracking system and method are provided. The location tracking system includes a plurality of tags which receive a read signal and which output tag signals, a reader which transmits the read signal to the tags, receives the tag signals, and identifies tag IDs from the tag signals, and a data processing system which stores location information of the tags and determines the location of the reader by using the tag IDs received from the reader based on the location information.