Patent ID: 11922257
Assignee: INSTITUTE OF MICROELECTRONICS, CHINESE ACADEMY OF SCIENCES
Field: Digital communication (Electrical engineering)
Classification: CPC G  H | IPC G

Claim 6:
7. An RFID system, comprising an RFID electronic tag and an RFID reader, wherein
the RFID electronic tag encodes a digital baseband signal to obtain a coded signal;
the RFID electronic tag performs a PSK modulation on the coded signal to obtain a first modulated signal;
the RFID electronic tag performs an OFDM modulation on the first modulated signal to obtain a second modulated signal;
the RFID electronic tag sends the second modulated signal to the RFID reader;
the RFID reader receives the second modulated signal from the RFID electronic tag;
the RFID reader performs an OFDM demodulation on the second modulated signal to obtain a first demodulated signal;
the RFID reader performs a PSK demodulation on the first demodulated signal to obtain a second demodulated signal; and
the RFID reader decodes the second demodulated signal to obtain the digital baseband signal;
wherein the RFID electronic tag performing the OFDM modulation on the first modulated signal further comprises:
the RFID electronic tag inserts pilots to the first modulated signal to obtain a first serial signal;
the RFID electronic tag performs a serial-to-parallel conversion on the first serial signal to obtain N first parallel signals, N being the number of subcarriers;
the RFID electronic tag performs an inverse discrete fast Fourier transform (IDFFT) on the N first parallel signals to obtain N second parallel signals;
the RFID electronic tag performs a parallel-to-serial conversion on the N second parallel signals to obtain a second serial signal; and
the RFID electronic tag adds cyclic prefixes to the second serial signal to obtain the second modulated signal.