Scientists at the Sandia National Laboratories have combined UWB radio signals with advanced encryption techniques to develop a secure sensor and communications network for the US military. This secure UWB communication system holds the promise of better protection of troops in the field by enabling better detection of enemy positions and by making it much harder for adversaries to eavesdrop or jam military communications.

"We are making military communications signals extremely difficult to detect, intercept or jam," said Sandia's Timothy Cooley, "by utilizing the immense spectrum of UWB to spread the energy of communications signals from sensors over such a wide frequency spectrum that the signal power falls below the noise floor of normal receivers. By combining UWB with AES [Advanced Encryption Standard], our signals are virtually impossible to crack."

UWB (aka "impulse radio") blankets a wide spectrum with short, 100 picosecond pulses which are below the noise floor of conventional radio receivers. If an enemy were to use special UWB receivers to listen in on the transmission, it is not likely that he would know how to reassemble the disparate data packets of each impulse into a coherent and meaningful whole. Were an enemy somehow to reassemble the packets, he would still have the daunting task of cracking the 256-bit AES encryption used in this secure military communications version.

In addition to this secure comunication, researchers are now working on adding a detection component to the system, fusing UWB communication with UWB radar. "By combining UWB radar and secure communications, we will be able to both detect the intrusion of insurgents as well as securely communicate their whereabouts."

For more on the secure UWB system:
- see R. Colin Johnson's EETimes report