Rfid System

A radio frequency identification tag comprising:

• an antenna terminal through which an energy pumping signal is received and tag identification information is transmitted;
• a memory in which the tag identification information is stored;
• a D/A converter converting the tag identification information into an analog signal in response to an information request signal included in the energy pumping signal;
• a clock extractor extracting a clock signal from the energy pumping signal;
• a frequency synthesizer operated according to the clock signal of the clock extractor, and generating a frequency;
• a radio frequency up converter up-converting a signal output from the D/A converter, and allowing the up-converted signal to be transmitted through the antenna terminal;
• and
• a power unit supplying internal power.

A radio frequency identification reader comprising:

• a transmitter generating an energy pumping signal for power supply of a radio frequency identification tag and signal supply of a clock synchronization signal and an information request signal;
• an antenna terminal emitting output of the transmitter as a high frequency signal, and receiving an orthogonal frequency division multiplexing signal from the radio frequency identification tag;
• a receiver demodulating tag identification information from the orthogonal frequency division multiplexing signal received from the antenna terminal;
• and
• a microprocessor controlling the transmitter and processing a signal demodulated in the receiver.