Optical Rotman Beamforming Lens for Multi-Function RF/Microwave/Millimeter Wave Antenna Systems

In this six-month Phase I program, ANRO Engineering, Inc. proposes to investigate the properties of compact, low-cost, two-dimensional fiber optic and integrated optic Rotman lenses for application to wideband, multi-function RF/microwave/millimeter wave antenna (MFA) systems. The photonic Rotman lens will enable the reception and transmission of simultaneous, multiple frequency, independent beams operating over radar/communication bands. The technical objectives of this proposed Phase I program are to: (1) investigate the feasibility of commercially available silica glass waveguide technology for fabrication of two-dimensional integrated fiber optic Rotman lens beamformers capable of operation at modulation frequencies from 0.5 - 10 GHz with extension to 40 GHz and beyond; (2) define the performance requirements and develop specifications for two- dimensional integrated Rotman photonic beamformers with up to 64 beam ports and 64 array ports; (3) carry out the electrical design of a two-dimensional, 16-beam port/16-array port integrated photonic Rotman beamformer for operation at RF/microwave modulating frequencies from 0.5 - 2.0 GHz. The proposed Phase I optional effort will carry out the mechanical design of the 2-D photonic Rotman lens described under technical objective (3) above, in conjunction with commercial suppliers of silica waveguide components in order to expedite the fabrication, assembly and test of prototype beamformer hardware under the Phase II program. Low-cost manufacturing methods and fabrication refinements to control mechanical tolerances impacting electro-optical performance parameters will be addressed in Phase II, also.