Economically efficient delivery of highly reliable electric power is increasingly dependent on networked SCADA (Supervisory Control and Data Acquisition System) and distributed control systems operating over commercially available, and frequently IP based, communication technologies. As cyber networks penetrate more and more into the physical infrastructure, there is a growing need for identification/development of communication mechanisms that are inherently secure with bounded performance metrics. It includes technologies such as security in physical layer and modeling and integration of heterogeneous communication architectures. ORNL has expertise and leadership in developing and deployment of secure wireless sensors for industrial process control and SCADA systems.
Hybrid spread spectrum (HSS) is a demonstrative wireless technology towards seamless secure communication. Spread-spectrum systems offer the flexibility of immediate (domestic) license-free operation in four distinct frequency bands and can be deployed in several other (military) bands to accommodate high data rates with high link integrity (i.e., low error rates), even in the presence of significant multipath effects and interfering signals. A more recent development involves the synergistic combination of direct-sequence spread-spectrum (DSSS) signaling with the use of integrally coordinated frequency hopping (FH) and/or time-hopping (TH) modulation, generically dubbed hybrid spread-spectrum (HSS). A highly useful form of this transmission scheme for various applications is the specific code-related combination of standard DSSS modulation with "fast" frequency hopping (FFH), termed "FastHSS," wherein multiple frequency hops occur within a single data-bit time. Specifically, the most significant benefit to fast frequency hopping is that each bit is represented by chip transmissions at multiple frequencies. If one or more chips are corrupted by multipath or interference in the RF link, statistically a majority should still be correct. When transmitted in an ultra wideband mode HSS provides inherent security at the physical layer because the signal is spread close to the noise floor avoiding pattern recognition over a rogue spectrum analyzer. HSS, once developed, can be used for applications ranging from SCADA systems to control systems and perimeter security.
