| 摘要 |
<p>A product information display system has electronic display tags for displaying pricing and product information for products in stores or warehouses. The electronic display tags (20) are electromagnetically coupled to a conductor (C1-Cn). A control circuit (31) is used to generate an information signal which contains a tag address and related data. A modulator circuit (82) modulates an a-c. power signal with the information signal and applies it to the conductor (C1-Cn) for transmission to the display tags. Each of the display tags (20) is equipped with a coil (110) that is electromagnetically coupled to the conductor for picking up the signals carried by the conductor (C1-Cn). A demodulator (146) is used to demodulate the signal picked up by the coil (110) to obtain the original information signal. Each of the display tags (20) is provided with a manually operated switch for initializing the tags with initial addresses transmitted by the conductor (C1-Cn). A microprocessor (146) in the electronic tag (20) then compares the address contained in subsequent information signals with the address stored in the tag's memory. If the addresses match, the microprocessor further processes the information signal for visual display or verification functions.</p> |
