Nfc receiver and operation method of circuit comprising the nfc receiver

A method of operating a near-field communication (NFC) circuit, the method comprising:

• receiving a first signal including an interference signal or a modulated data signal through an antenna;
• attenuating a magnitude of the received first signal;
• down-converting a frequency of the first signal having the attenuated magnitude based on a local oscillation signal having a frequency for communication of the NFC circuit;
• filtering the data signal included in the frequency down-converted first signal;
• and
• adjusting a magnitude of the filtered data signal,
• wherein the attenuating the magnitude of the received first signal comprises attenuating the magnitude of the first signal such that linearity of the data signal is maintained in signal processing performed on the first signal in the down-converting of the frequency of the first signal, the filtering of the data signal, and the adjusting of the magnitude of the filtered data signal, and
• wherein the adjusting of the magnitude of the filtered data signal comprises adjusting the magnitude of the filtered data signal such that the filtered data signal has a sufficient magnitude for demodulating without saturation.

A near-field communication (NFC) receiver performing communication through an antenna, the NFC receiver comprising:

• a first adjusting unit configured to receive a data signal or an interference signal through the antenna, and attenuate a magnitude of the data signal or the interference signal based on a first attenuation value;
• a mixer configured to down-convert a frequency of the data signal or the interference signal output by the first adjusting unit;
• a filter configured to filter the data signal from the data signal or the interference signal output by the mixer;
• a second adjusting unit configured to receive the filtered data signal and adjust a magnitude of the data signal based on a first gain value;
• and
• an automatic gain controller (AGC) configured to adjust the first attenuation value based on the magnitude of the data signal or the interference signal that is attenuated using the first adjusting unit, and to adjust the first gain value based on the magnitude of the data signal that is adjusted using the second adjusting unit,
• wherein adjusting the magnitude of the data signal comprises one of amplifying the magnitude of the data signal and attenuating the magnitude of the data signal.

A method of operating a near-field communicator (NFC) circuit, the method comprising:

• receiving a data signal and an interference signal;
• attenuating the data signal based on an attenuation value while maintaining linearity of the data signal;
• attenuating the interference signal based on the attenuation value while maintaining linearity of the interference signal;
• and
• adjusting a magnitude of the data signal based on a gain value,
• wherein the gain value is adjusted based on a comparison between a power of the data signal and a threshold value stored in the NFC circuit.