Near field communications (NFC) device having adjustable gain

摘要

A near field communications (NFC) device is disclosed that is capable of optimizing a gain for received signals. Measurements are made of signals received from an NFC environment and are compared to one or more threshold hold values. Based on the comparison, it is determined whether the measurements indicate underamplification or overamplification. Depending on the results of the analysis, one or more components within the NFC device is adjusted to increase or decrease the gain, respectively. The measurements may be taken during an unloaded baseline state or during loading, and may be compared to previous measurements to estimate their accuracy.

主权项

1. A near-field communication (NFC) device that operates within an NFC environment, the NFC device comprising:
a transmitter module, including an amplifier, configured to turn on a magnetic field to transmit a transmission signal to the NFC environment; a receiver module configured to receive a signal from the NFC environment in response to the magnetic field, the receiver module including:
a signal detection module configured to detect the received signal within a predetermined time from the turning on of the magnetic field of the transmitter module;a decoder module configured to decode the received signal; anda gain adjustment module configured to:
measure the received signal to produce a measurement;compare the measurement to a first threshold value and a second threshold value; andadjust a component of the amplifier, the signal detection module, or the decoder module when the measurement is not between the first threshold value and the second threshold value, wherein the predetermined time is sufficiently short so as to prevent a second NFC device within the NFC environment from responding to the transmission signal.