Multi-element true time delay shifter for microwave beamsteering and

Abstract

In a broad aspect the present invention comprises a multiple element, multi-throw electronic switch for a fiber optical cable network. The multiple element, multi-throw electronic switch includes a bulk media optical deflector angularly controllable by selectable electronic steering signals. At least one multiple element, multi-throw electronic switch is use to construct a true time delay shifter using rows of a plurality of columns of a plurality of beamsteering optical fiber delay lines, all with a specified antenna scanning coherence center. Distributed beamsteering is performed by selecting from the composite array, subarrays for which a common steering direction cosine can be applied to that subarray. The distributed beamforming is performed by combining elements beamsteered with a common antenna scanning coherence center from an electronically small core fibers with limited available modes into larger core multimode fibers. The distributed beamsteering and distributed beamforming is iterated until all antenna elements in the composite array have been beamsteered into an array with the identical specified antenna scanning coherence center. The bulk media optical deflector angularly controllable by selectable electronic steering signals has the additional advantage that a plurality of squint-free antenna beamsteering commands can be simultaneously implemented providing a frequency-independent means of antenna beam shaping which necessary for a frequency-independent monopulse processing capability.