Multipath Encryption and Authentication System

We propose to develop a novel, fail-proof method by which wireless users' will be able to verify each others identity based on details of the physical environment only accessible to those users. The approach allows fairly non-complex and compact hardware apart from the radios. It is based on the fundamental property of RF waves that RF waves are invariant under time reversal. The idea is most easily explored with impulse radio (Ultra Wide Band, or UWB), but also extends to conventional narrowband communications. IAI has extensive experience with the characterization of UWB multipath signals. This proposal explains some preliminary experiments that demonstrate this idea. During our Phase I effort, we will measure UWB multipath signals by using UWB radios in scanning receiver mode and develop a thorough characterization of multipath signals for some environments of interest. After developing algorithms to distill a robust (under small experimental variations of the signal) password from the multipath signal, we will incorporate these algorithms with the radios' own algorithms. By the end of phase I, we will demonstrate our complete hardware and software for this application.