Abstract: An RFID transponder detector is provided having a coupled oscillator system. Coupled first and second LC of the system produce a detection signal each time a combination of pulses is applied to the LC pairs. Application of the pulses is repeated periodically to produce a sequence for detection signals having two different first and second detection frequencies. Transmitting the sequence of detection signals results in corresponding first and second response signals having the first and second detection frequencies at the LC pairs. Values of a preselected detection parameter for the detection signals are compared to the values of the detection parameter for the response signals to determine if a transponder having a transponder resonant frequency corresponding to the first or second detection frequency is present in a proximal space of the transponder detector.

Abstract: An apparatus is provided that includes a bar code emulator for translating an RF carrier signal modulated, preferably, using the American Standard Code for Information Interchange (ASCII) symbology into a signal suitably formatted for input to a standard bar code decoder. A sensor interface is included in the bar code emulator for demodulating the RF signal. A control interface is included for specifying the format of the resulting signals. A processor translates the ASCII symbols according to the format specified at the control interface. The resulting signals are output on a decoder interface that communicates with the standard bar code decoder.