An NFC device that receive a data frame with a start pattern including first and second pattern signals, and a data pattern corresponding to the start pattern. The NFC device comprising an analog-to-digital converter which generates first and second input signals based on the first and second pattern signals, respectively, a modem that includes a first sub-matched filter which multiplies a first match signal by the first and second input signals to respectively calculate first and second result values of the first match signal and multiplies a second match signal by the first and second input signals to respectively calculate first and second result values of the second match signal. The first sub-matched filter determines reception of the start pattern when the first and second result values of the first match signal or the first and second result values of the second match signal exceed a predetermined start pattern threshold.