Patent ID: 7986916

Claim:
A near field radio frequency (RF) communicator, comprising: a coupler configured to receive a modulated RF signal by inductive coupling; a demodulator configured to receive the modulated RF signal, the demodulator comprising: a first multiplier configured to multiply the modulated RF signal by a first RF signal to produce an in-phase modulated signal, and a second multiplier configured to multiply the modulated RF signal by a second RF signal, in phase quadrature with the first RF signal, to produce a quadrature-phase modulated signal; and a demodulation processor comprising: a first and a second peak detector configured to detect negative and positive peaks in the in-phase modulated signal and the quadrature-phase modulated signal, respectively, a first difference calculator configured to determine a first difference between negative and positive peaks detected by the first peak detector, a second difference calculator configured to determine a second difference between negative and positive peaks detected by the second peak detector, a combiner configured to determine a length of a vector representing a difference between the negative and positive peaks by adding the first and second differences, and a controller configured to determine whether a logic state transition has occurred based upon the length of the vector to enable data to be extracted from the modulated RF signal.