Enhanced Wireless Cellular Packet Transmission Security via Spatial Diversity

60237 Wireless communications sometimes require not only secure two-way communications but also mutual and continuous authentication of the identity and position of mobile units and cellular network control stations. This is particularly important for treaty verification, for the transport of munitions, fissile material and currency, and for vehicle control and tracking within both government and commercial facilities. This project will develop the Spatial Diversity Encryption Chaffing Interface system, which splits a secure communication into a stream of packets and distributes transmission across all cells within range of the mobile unit. The spatial distribution of the cell sites then implicitly encodes the identity of each packet by direction of propagation, time of flight, and spatial modulation. In Phase I, a prototype wireless cellular packet network implementing spatial diversity as an entirely novel security feature was successfully implemented, incorporating both spatially diverse transceiver hardware and complementary sequenced chaffing and winnowing software within a small wireless local area network. Operation of larger cellular networks with multiple mobile units and a large number of cell site concentrators was verified via simulation. In Phase II, a comprehensive system for secure communications and continuous mutual authentication of identity and position of mobile units on a cellular packet network will be developed. Also, a comprehensive secure packet transmission protocol and interactive network management interface will be demonstrated. Commercial Applications and Other Benefits as described by the awardee: The proposed system should bring secure authenticated communication to cellular handsets and mobile stations as well as to armored car fleets and other carriers of valuable or sensitive materials. By constantly verifying the position and route of mobile units, the system will safeguard against hijacking, theft, ambush, and diversion while maintaining a reliable positive control link for secure transport fleets.