Abstract: A method for preparing hydrogen from ammonia by using pressure swing adsorption (PSA) is provided. The method for preparing hydrogen from ammonia, of the present invention, comprises the steps of: generating hydrogen and nitrogen from ammonia gas through a high-temperature reaction by using a catalyst; performing purification by selectively adsorbing unreacted ammonia gas from a gas containing unreacted ammonia and low-purity hydrogen and nitrogen, which are supplied through the high-temperature reaction and cooled; and performing purification by separating high-purity hydrogen from the gas consisting of low-purity hydrogen and nitrogen, wherein purification is carried out by using a carbon molecular sieve (CMS) adsorbent so as to desorb the unreacted ammonia gas through PSA.

Abstract: A tag of an apparatus for simultaneously identifying massive tags according to the present invention may include an analog circuit unit to communicate with a reader through an analog signal and to receive energy via magnetic coupling with the reader. Further, the tag may include a digital circuit unit to be supplied with power from the analog circuit unit. The digital circuit unit may support a sleep mode for the tag to stand by in a low power state after transmitting an identifier (ID) to the reader and a wait mode for controlling random access to the reader.

Abstract: Provided is a symbol synchronization apparatus and method of a passive RFID reader. The symbol synchronization apparatus includes: an edge clock detector generating edge clocks by detecting phase inversion positions of a received signal; a preamble detector detecting a preamble section by analyzing the generation times of the edge clocks; a symbol decision time extractor extracting a symbol decision time by averaging distances between the edge clocks consecutively generated in the preamble section, when the preamble section is detected; and a symbol decider deciding a symbol by analyzing the magnitude of the received signal, when the time reaches the symbol decision time.

Abstract: Disclosed are a passive RFID (Radio Frequency Identification) system and method capable of recognizing a great deal of tags at a high speed. A reader of a passive RFID system, including: a processor dividing slots and subchannels to configure a round, recognizing subchannels that are not involved in a collision and interference by the slots, and changing the subchannels that are not involved in a collision and interference, into a sleep state; a transmission unit encoding a command generated through the processor, performing an amplitude jitter modulation on the encoded command, and transmitting the modulated command; and a reception unit acquiring and demodulating tag signals received through a plurality of subchannels by the slots, and providing the demodulated tag signals to the processor.

Abstract: A tag of an apparatus for simultaneously identifying massive tags according to the present invention may include an analog circuit unit to communicate with a reader through an analog signal and to receive energy via magnetic coupling with the reader. Further, the tag may include a digital circuit unit to be supplied with power from the analog circuit unit. The digital circuit unit may support a sleep mode for the tag to stand by in a low power state after transmitting an identifier (ID) to the reader and a wait mode for controlling random access to the reader.

Abstract: Provided are an RFID reader and a method for suppressing transmission leakage signals thereof. The RFID reader includes a first loop, a second loop, and a digital signal processor. The first loop suppresses a first transmission leakage signal of an RX signal in response to a first leakage control signal. The second loop suppresses a second transmission leakage signal of the RX signal, received through the first loop, in response to a second leakage control signal. The digital signal processor generates the first leakage control signal and the second leakage control signal. The digital signal processor generates the first leakage control signal until the level of the first transmission leakage signal becomes equal to or lower than the level of a first reference transmission leakage signal.

Abstract: The present invention relates to an apparatus and method for detecting the collision of Radio Frequency IDentification (RFID) tags. In the apparatus and method for detecting the collision of RFID tags, when a subcarrier signal from which a carrier signal has been removed by a reader ASK analog demodulation device is inputted to a baseband receiver, a peak signal for the received tag signal is generated, and useful information about the generated peak signal within a symbol section is extracted. In the case where a collision is generated because two or more tags send signals to an RFID reader at the same time when the RFID reader communicates with the tags, the RFID reader can effectively detect the collision between the tags.

Abstract: The RFID reader of an RFID system includes a processor for processing a command for the RFID tag and a response from the RFID tag, a modem for modulating the command from the processor or demodulating the response from the RFID, and an RF unit for transmitting the modulated command transferred from the modem to the RFID tag or receiving the response from the RFID tag and transferring the response to the modem. The RFID tag of the RFID system includes a power supply unit for generating energy using a radio wave received from the RFID reader, a receiver for demodulating a signal received from the RFID reader, a data processor for performing operation according to the signal demodulated by the receiver, and a transmitter for backscattering a signal from the data processor.

Abstract: Disclosed are a passive RFID (Radio Frequency Identification) system and method capable of recognizing a great deal of tags at a high speed. A reader of a passive RFID system, including: a processor dividing slots and subchannels to configure a round, recognizing subchannels that are not involved in a collision and interference by the slots, and changing the subchannels that are not involved in a collision and interference, into a sleep state; a transmission unit encoding a command generated through the processor, performing an amplitude jitter modulation on the encoded command, and transmitting the modulated command; and a reception unit acquiring and demodulating tag signals received through a plurality of subchannels by the slots, and providing the demodulated tag signals to the processor.

Abstract: Provided are an RFID reader and a method for suppressing transmission leakage signals thereof. The RFID reader includes a first loop, a second loop, and a digital signal processor. The first loop suppresses a first transmission leakage signal of an RX signal in response to a first leakage control signal. The second loop suppresses a second transmission leakage signal of the RX signal, received through the first loop, in response to a second leakage control signal. The digital signal processor generates the first leakage control signal and the second leakage control signal. The digital signal processor generates the first leakage control signal until the level of the first transmission leakage signal becomes equal to or lower than the level of a first reference transmission leakage signal.

Abstract: Provided is a symbol synchronization apparatus and method of a passive REID reader. The symbol synchronization apparatus includes: an edge clock detector generating edge clocks by detecting phase inversion positions of a received signal; a preamble detector detecting a preamble section by analyzing the generation times of the edge clocks; a symbol decision time extractor extracting a symbol decision time by averaging distances between the edge clocks consecutively generated in the preamble section, when the preamble section is detected; and a symbol decider deciding a symbol by analyzing the magnitude of the received signal, when the time reaches the symbol decision time.

Abstract: Provided are a mobile Radio Frequency Identification (RFID) device and a data communication method thereof. In the method, a mobile communication terminal unit provides a command to an mRFID reader unit and receives a response to the command from the mRFID reader unit. It is checked whether there is an error in a protocol message of the command or the response, and the command to the mRFID reader unit according to a check result is re-transmitted.

Abstract: A demodulation apparatus for a Radio Frequency Identification (RFID) reader includes: a direct current (DC) offset cancellation unit for cancelling DC-offset noise contained in a PSK-modulated or ASK-modulated subcarrier tag signal from the tag signal when the tag signal is received; and a subcarrier digital demodulator for eliminating a subcarrier from the tag signal from which DC-offset noise has been cancelled to demodulate the DC-offset noise-cancelled tag signal.

Abstract: An apparatus for automatically performing channel change of a television receiver using a video cassette recorder includes a playback command detector for detecting a playback command, a channel sensor for sensing a video viewable channel which is selected by a radio frequency changeover switch according to a user's selection, a memory for storing the video viewable channel sensed by the channel sensor, television receiver channel change data and television receiver codes corresponding to different types of the television receiver, a controller for reading one of the television receiver channel change data stored in the memory corresponding to the video viewable channel sensed by the channel sensor upon the detection of the playback command by the playback command detector, and a remote transmitter for remotely transmitting the television receiver channel change data from the controller to the television receiver to change a current channel of the television receiver to the video viewable channel sensed by th

Abstract: An apparatus and a method of controlling tracking in slow mode playback. The tracking control apparatus comprises a video head for detecting a video signal recorded on a magnetic tape, a video signal processing circuit for detecting envelopes of the detected video signal from the video head, a microcomputer for outputting servo data and a slow tracking signal in response to the detected envelopes from the video signal processing circuit, a servo device for outputting a capstan phase control signal in response to the servo data from the microcomputer, and a capstan motor for driving a capstan in response to a signal into which the capstan phase control signal from the servo device and the slow tracking signal from the microcomputer are combined.