AUTOMATIC ANTENNA TUNER SYSTEM FOR RFID

摘要

An automatic antenna tuner system for radio frequency identification system includes a pulse width modulator, a microprocessor for controlling the generation of a source signal from the modulator, capacitors for receiving the source signal from amplifiers and transmitting it to an inductor, a gate communicating with the capacitors for transmitting a resonating signal from the inductor and capacitors as a carrier signal and means for gating the carrier signal with the source signal to produce a compared signal to produce a string of pulses and means for varying capacitance to increase or decrease the count of the string of pulses.