Special Technology Area Review on Optical Control of Phased Arrays

Abstract

Abstract : Future DoD systems requirements will push current device electronics technology beyond its limits. Therefore, new technology will have to be developed to meet these requirements. One particular type of system, the phased array radar, has been given particularly stringent future requirements for size, weight, and performance. In an effort to try and meet these requirements several DoD agencies have conducted preliminary research in replacing the coaxial cable in current phased array radars with fiber optic cable. Unlike ordinary coaxial cable, fiber optic cable can carry an RF signal juxtaposed on a light wave, with very little attenuation or dispersion over wide frequency bandwidths. Furthermore, the fiber optic cable is mechanically more flexible and approximately 75% smaller and lighter than ordinary coaxial cable, allowing it to be assembled in more compact modules. Fiber optic cable is also impervious to harmful electromagnetic radiation. Consequently, fiber optic cables are presently being considered to replace the coaxial cable in phased arrays for such functions as RF signal distribution, phase shifter amplitude taper controls, true time delay beamforming and data transmission in systems with digital beamforming. As one of its many functions as an advisor to the DoD, the Advisory Group on Electron Devices (AGED) conducted a Special Technology Area Review (STAR) to examine and assess optically integrated phased array configurations by AGED Working Groups A (Microwaves) and C (Electro-optics) on 12 March 1992. The report summarizes the information presented at the STAR and outlines the findings and recommendations that emerged from an extended review of the area by those working groups.