Method for controlling a modulation index of a near field communication device with aid of dynamic calibration, and associated apparatus

An apparatus for controlling a modulation index of a near field communication (NFC) device, the apparatus comprising at least one portion of the NFC device, the apparatus comprising:

• a transmitter, positioned within a chip of the NFC device, arranged to transmit data for the NFC device;
• a receiver, positioned within the chip of the NFC device, arranged to receive data for the NFC device, wherein in a calibration mode of the NFC device, the receiver is temporarily coupled to the transmitter to form a probing path between the receiver and the transmitter;
• and
• a control circuit, positioned within the chip of the NFC device and coupled to the transmitter and the receiver, arranged to control operations of the NFC device, wherein in the calibration mode of the NFC device, the control circuit dynamically adjusts at least one portion of a plurality of modulation parameters corresponding to the modulation index according to probed results of outputs of the transmitter, in order to calibrate the modulation index, for use of transmitting through the transmitter in a normal mode of the NFC device.