Patent ID: 8890658

Claim:
An RFID system comprising: an RFID tag; and a reader device communicating with the RFID tag, wherein the RFID tag includes: N load-modulators and N antennas communicating with the reader device in any one scheme of M-pulse amplitude modulation (M-PAM) and M-quadrature amplitude modulation (M-QAM) in which modulation of an M level is performed and operated corresponding to the M level; a code generating unit adding a parity to data stored in the RFID tag to generate an error correcting code; and a preamble signal generating unit generating a preamble code having auto-correlation characteristics of a delta function, wherein N load-modulators and N antennas transmit the error correcting code and the preamble code to the reader device in any on scheme of M-pulse amplitude modulation (M-PAM) and M-quadrature amplitude modulation (M-QAM) in which modulation of the M level is performed and operated corresponding to the M level.