SBIR-STTR Award

A Novel Multibeam Phased Array Beamformer technology development is described suitable for Transformational Communications applications. The beamformer will be designed for Advanced EHF satellite downlink and uplink payloads and create many simultaneous high gain pencil beams feeding a planar array of 2,000 or more elements from geostationary earth orbit. The beamformer uses row and column two dimensional Rotman lens stacks feeding sub arrays of contiguous more closely spaced elements. Radiating sub array elements each have phase shifters for beam fine steering and shaping within the equilateral triangular beam lattice of the Rotman lens stacks capable of covering the entire 17.4º earth disc. The sub arrays are arranged in a triangular (hexagonal) element lattice to minimize the number of elements and hence passive and active components needed. The Rotman lens stacks themselves feed the sub arrays directly through each of their array ports. At each beam port of the Rotman lens stack, a narrow pencil beam is formed that has frequency independent beam pointing angle due to the true time delay nature of the Rotman lens phase excitation creation. Within each of these beams, the sub array phase shifters provide fine steering.

Benefits:
The beamformer technology should be applicable to EHF and SHF Milsatcom military applications. It is also suitable for high data rate internet access applications to service a great number of commercial or military customers. The beamformer should be directly applicable to the goals of Transformational Communications. Although designed to cover the entire earth disk with thousands of high gain pencil beams; the beamformer may be configured on orbit for specific earth coverage including precisely shaped high efficiency beams. The technology can be extended to space or ground based arrays up to 400,000 elements, frequency ranges in L, S, or X bands, and bandwidths up to 20% and any scan sector.

Keywords:
MILSATCOM, Advanced EHF, Multibeam, Phased-Array, Transformational Communications, Rotman lens, Sensors, Battlespace

A Novel Multibeam Phased Array Beamformer technology development is described suitable for Transformational Communications applications. The beamformer is being designed for Advanced SHF/EHF satellite downlink and uplink payloads and creates simultaneous high gain pencil beams feeding a planar array of 2,000 or more elements from geostationary earth orbit. The beamformer uses column and row two dimensional Rotman lens stacks feeding sub arrays of contiguous elements arranged in an equilateral triangular element lattice to minimize the number of elements and hence passive and active components needed. Radiating sub array elements each can have phase shifters for beam fine steering and shaping within the equilateral triangular beam lattice of the Rotman lens stacks capable of covering the entire 17.4º earth disc with 1200 to 2000 narrow "pixel" beams. At each beam port of the Rotman lens stack, a narrow pencil beam is formed that has frequency independent beam pointing angle due to the true time delay nature of the Rotman lens phase excitation creation. Pixel beams are combined, steered and shaped within the RF Beam switch/combiner matrix resulting in a minimum of 64 simultaneous independent communication beams. Demonstration of an active EHF array column is proposed for risk reduction in Phase II.

Benefits:
The beamformer technology should be applicable to EHF and SHF Milsatcom military applications. It is also suitable for high data rate internet access applications to service a great number of commercial or military customers. The beamformer should be directly applicable to the goals of Transformational Communications. Although designed to cover the entire earth disk with thousands of high gain pencil beams; the beamformer may be configured on orbit for specific earth coverage including precisely shaped high efficiency beams.

Keywords:
MILSATCOM, Advanced EHF, Multibeam, Phased-Array, Transformational Communications, Rotman lens, Sensors, COTM