2-D localization and identification based on SAW ID-tags at 2.5 GHz

An identification and localization system based on surface acoustic wave (SAW) radio sensors is presented in this paper. This system is able to identify and localize objects within a two-dimensional area. Identification is achieved with a fixed coded passive SAW identification-tag. Localization is carried out with three receiving antennas and with a following analysis of time delay between the sent interrogation signal and the received signals. For practical tests, a special interrogator has been established, as well as the receiving and demodulation unit. The whole system is controlled by a computer.