Intellectual Merit: The potential advantages of optical wireless communication fall short of reasonable expectations if adverse effects caused by atmospheric turbulence are not accurately compensated for. Adverse weather conditions degrade the performance of the system, causing increased bit error rate (BER), packet loss and network delays, as well as decreased network throughput. The objective of this project is to design a hybrid optical/RF system that is resistive to degradations caused by poor optical channel condition due to atmospheric turbulence. Combinations of experimental research and theoretical modeling will be utilized to realize such a system. The research will include the design of an optical transceiver that will efficiently handle optical transmission using different wavelengths while maintaining a light-weight optical interface and consuming minimal power. The research will examine the use of proper wavelengths for data transmission to minimize the influence of weather and maximize range without increasing transmission power. Current optical channel estimation algorithms will be examined and suitable ones will be developed based on multi-frame averaging. Estimation will be carried out using available wavelengths. The hardware design and software algorithms for the most current methods of pointing, acquiring, and tracking (PAT) will be examined to support optical communication between mobile aerial vehicles and stationary vehicles fixed at pre-determined, known locations.
Broader Impacts: The direct impact of the proposed project is the development of a unique optical transceiver, which will implement multiple wavelengths. Results of the work would make free-space optics a viable option for various wireless applications. Hence, the demand for all-time connectivity that is currently satisfied through the use of RF technologies may shift toward using optical technologies. This could aid by curbing the rapid increase in RF noise level caused by the almost daily introduction of a number of various RF devices. Results of the work have airborne Internet and battlefield communication applications. Graduate students will be trained, and a major undergraduate training program is leveraged.
