| 摘要 |
<p>A method and apparatus for providing information concerning products, using radio frequency transmissions. A host computer transfers information relating to a product to a radio frequency transmitter. The information is transmitted to a transceiver built into a label for the product, the label being located near a shelf of a gondola that is holding the product. The transmission from the transmitter to the transceiver may be made through one or more repeaters. A label transceiver for another product can act as a repeater, upon instruction from the host computer. When the intended label transceiver correctly receives the information concerning the product, it retransmits an acknowledgement back to the host computer along the same transmission path by which the information reached the transceiver. The transceiver stores the information relating to the product in the label. The transceiver and label are powered by a photovoltaic cell that transforms ambient light into electrical energy. If the ambient light decreases, in order to save electrical energy, the transceiver is first turned off. If it is necessary to save further electrical energy, the label display is next turned off. If the ambient light then increases, the display and then the transceiver are turned back on.</p> |
