The U.S. Army Research Laboratory (ARL) has developed a framework to study how easily ultraviolet communication (UVC) systems can be detected. Although the work focuses on longer-term applications, it could ultimately enable more secure network connectivity for soldiers in adversarial environments. Deep UV wavelengths have propagation characteristics that allow for a non-line-of-sight (NLOS) optical link that can make deep-UV communications harder for an adversary to detect. “The increased atmospheric absorption of deep-UV wavelengths implies that UV communication, or UVC, has a natural low probability of detection, or LPD, characteristic,” ARL researcher Robert Drost said. “In order to fully take advantage of this characteristic, a rigorous understanding of the LPD properties of UVC is needed.” Army researchers developed an analysis framework that enables the rigorous study of the detectability of ultraviolet communication systems, providing the insights needed to deliver the requirements of future, more secure Army networks. Courtesy of K. Kassens. The researchers outlined a modeling framework to quantitatively study the LPD characteristics of UVC. They described the LPD modeling framework, starting with the UVC LPD channel model geometry, followed by a description of the transmission requirements for a desired bit-error rate, and concluding with an analysis of the resulting adversarial detection probability. They applied their framework to various friendly and adversarial system configurations to achieve insights into the LPD characteristics of UVC. They concluded: Adversarial line-of-sight (LOS) detection of a NLOS communication link is not as significant a concern as previously thought. Steering of a UVC transmitter does not appear to be an effective detection-mitigation strategy. An LOS UVC link provides LPD standoff distances that are commensurate with the communication range. In future work, the researchers plan to extend this framework to consider the effects of a wider number of friendly and adversarial system parameters, as well as broader operations scenarios, including UVC networks. Another key effort involves the experimental characterization, exploration, and demonstration of UVC technology in a practical network using ARL’s Common Sensor Radio, a mesh-networking radio designed to provide robust, energy-efficient networking. This research supports the laboratory’s goal of studying the integration of low-signature communications technologies with advanced camouflage and decoy techniques. Drost said that the work is also an on-ramp to studying how UVC and other communications modalities, including conventional radio-frequency communications, can operate together in a seamless, autonomous, heterogeneous network, which the ARL researchers believe is needed to fully realize the benefits of individual new communication technologies. “The future communications and networking challenges that the Army faces are immense, and it is essential that we explore all possible means to overcoming those challenges,” Drost said. The research was published in Optics Express, a publication of The Optical Society (OSA) (www.doi.org/10.1364/OE.399196).