Abstract: 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.

Abstract: A method and apparatus for providing spread spectrum communications. The apparatus starts with designated spread spectrum communications parameters, such as default transmitted power level, pseudo-noise (PN) sequence, PN sequence length, and frequency channel, having values which are chosen to ensure that spread spectrum communications can be carried out between a first station and a second station. The apparatus of the invention then changes the values of the spread spectrum communications parameters to the minimum values necessary to provide a given level of communications reliability. If the conditions facing the spread spectrum communication system change so that communications reliability falls below the given level, the apparatus resets the values of the spread spectrum communications parameters to the default levels and begins again to change their values to provide the given level of communications reliability.