Abstract: A computer-implemented method for redeeming an electronic coupon comprises receiving on a transmit device the electronic coupon that includes an embedded identifier that indexes coupon data; playing the identifier of the electronic coupon over air from a speaker of the transmit device in proximity to a receive device; decoding the identifier in response to the receive device receiving the audio signal over the air; and using the identifier to access the coupon data including purchase discount information.

Abstract: Methods and systems for providing a long-range real-time location system comprise transmitting a power signal from one or more exciters to at least a portion of the tags, wherein the exciters are located a distance from the tags within a range required to power the tags; initiating transmission of the power signal by a reader that transmits a command signal instructing the exciters to transmit the power signal to the tags, wherein the reader is located a greater distance from the tags than the range required to power the tags; receiving by multiple wideband antennas on the reader, wideband signals from at least one of the tags, and associating with the wideband signals a time of arrival at each of the wideband antennas; and calculating by the reader a location of the at least one tag based on differences between the time of arrival at each of the wideband antennas.