High Speed Digital Fiber-Optic Links for Control, Video and RF Telemetry Data from Remote Locations

Abstract

With the advent of high-speed parallel-to-serial conversion interface standards reaching the 1.6 gigabit per second region, it is now possible to remote entire telemetry tracking systems over long distances without the need to maintain receivers, combiners, computers and antenna control units at the pedestal. In addition, it will soon be possible to digitize the RF signal(s) with high-speed flash-video analog-to-digital converters and transfer the data over these same links. This coupled with the improvements in fiber-optic L.E.D. and laser transmitters/ receivers and the constantly decreasing cost of fiber-optic cable, will allow for the eventual elimination of copper cabling for these interfaces. This will net a cost savings for the end user, provide for easier installations and increase the reliability of the overall system. This paper gives a brief history of the development of high-speed fiber-optic interface links, then expands into current interface standards and their utilization (such as MIL-STD-1553B, fiber data distributed interface (FDDI), HIPPI, etc.). Finally, a glimpse into the future of telemetry systems and the possibilities to soon be realized as major manufacturers of fiber-optic interfaces push well into the gigabit region. Topics include: • Replacement of existing copper cables between controller and pedestal using fiber-optic cable with interfaces that are not software-based intensive (black boxes); • Multiplexing pedestal control and status lines, RF feed commands, scan reference signals, and boresite video camera control; • Connecting and controlling multiple controllers and/or pedestals through one common interface cable; • Operating multiple tracking stations through one remote antenna controller; • Digitized RF telemetry signals sent along with pedestal, feed, video commands and status.