| 摘要 |
<p>A dual standard RF-ID protocol system which can receive and recognize HDX and FDX transponder signals comprising an antenna circuit (10,12,20,22) for transmitting an excitation signal to charge-up HDX transponders and immediately initiate FDX transponders to respond. The antenna circuit comprises first (10,12) and second (20,22) pole circuits for receiving an HDX transponder RF frequency response signal having a first frequency and a FDX transponder RF frequency response signal having a second frequency. A mixer/amplifier circuit (24) mixes the HDX transponder RF frequency response signal from the first frequency down to the second frequency. A demodulator circuit (30) is operatively connected to the mixer/amplifier circuit for demodulating the FDX and the HDX frequency signals into a data signal. <IMAGE> <IMAGE></p> |
