Raytheon Company

Nitesh N Shah

Delmar L Barker

Harry A Schmitt

William Owens

Hao Xin

Ross D Rosenwald

Donald E Waagen

Andrew Greentree

Dennis J Garrood

Samantha S Livingston

Andrew D Greentree

A system for signature prediction and feature-level fusion of a target according to various aspects of the present invention includes a first sensing modality for providing a measured data set. The system further includes a processor receiving the measured data set and generating a first k-orthogonal spanning tree constructed from k orthogonal minimal spanning trees having no edge shared between the k minimal spanning trees to define a first data manifold. A method for signature prediction and feature-level fusion of a target according to various aspects of the present invention includes generating a first manifold by developing a connected graph of data from a first sensing modality using a first k-orthogonal spanning tree, generating a second manifold by developing a second connected graph of data from a second sensing modality using a second k-orthogonal spanning tree, and aligning the first manifold and the second manifold to generate a joint-signature manifold in a common embedding space.

Methods and apparatus for signature prediction and feature level fusion

The present invention describes a system and method of OAM diverse signal processing using classical beams for applications in which OAM signal character is controlled such as optical tagging and applications in which OAM signal character is not controlled such as clutter mitigation and interference cancellation for target detection, identification etc. This is accomplished by transmitting a source beam having a prescribed state with one or more non-zero OAM components, reflecting the beam off a 'tagged' or 'untagged' target and receiving the return beam in the direct return path to measure the one or more OAM components to identify the target. OAM processing provides additional degrees of processing freedom to greatly enhance the processing capabilities to detect and identify both &#x2018;tagged&#x2019; and &#x2018;untagged&#x2019; targets.

System and method of orbital angular momentum (OAM) diverse signal processing using classical beams

A band gap discontinuity is propagated across a Photonic Crystal (PC) to capture thermal energy in a region near the primary emission wavelength of the Planck spectral distribution and transfer that energy to a different spectral region where it is emitted. To extend the range of frequency shifting beyond the width of a single band gap, the intrinsic control parameters (e.g., lattice geometry factors, scattering element geometric factors, and variations in the index of refraction) are spatially varied across the PC to form a band gap gradient. Propagation of the band gap discontinuity, starting in the infrared wavelength region where the thermally generated electromagnetic energy is concentrated and propagating towards the long wavelength region, locally captures the thermal electromagnetic radiation, shifts it downwards in frequency, and pushes the lower-frequency thermal electromagnetic radiation on to the next region. The same principles apply to shift the frequency to shorter wavelengths. A PC-based power combining and waveguide structure can be constructed in the same or a surrounding structure to combine and guide the shifted radiation to an antenna or exit aperture.

Dynamic control of planck radiation in photonic crystals

On-chip multispectral imaging and data management is provided in the form of an Adaptive Focal Plane Array (AFPA) that is capable of spectral tunability at the pixel level. Layers of photonic crystals are registered with pixels of a broadband focal plane array. Spectral tuning is accomplished by switching the photonic crystal layers on/off and/or by changing their material structure to tune their photonic band gaps and provide a passband for incident photons. The photonic crystal layers are preferably segmented to independently address different regions or 'cells' of pixels down to a pixel-by-pixel resolution. The AFPA may simultaneously sense different regions of a scene at different spectral wavelengths, spatial resolutions and sensitivities.

Multispectral imaging chip using photonic crystals

Although THz radiation is naturally emitted by hot objects, the intensity levels are too weak to be considered as a practical THz source for most applications. Photonic crystal structures are used to modify the thermal emission peak associated with the standard Planck blackbody spectral distribution so that the THz region is dramatically enhanced. The photonic crystal core is preferably combined with variable Q defect cavities and a wave guiding and power combining structure so that the radiated THz energy is efficiently collected and directed to an output antenna. Higher THz emissions are realized by embedding a finer (higher frequency) photonic crystal structure within a coarser (lower frequency) structure.

Thermally powered terahertz radiation source using photonic crystals

A device is provided that can capture and store electrically neutral excited species of antimatter or exotic matter (a mixture of antimatter and ordinary matter), in particular, excited positronium (Ps*). The antimatter trap comprises a three-dimensional or two-dimensional photonic bandgap (PBG) structure containing at least one cavity therein. The species are stored in the cavity or in an array of cavities. The PBG structure blocks premature annihilation of the excited species by preventing decays to the ground state and by blocking the pickoff process. A Bose-Einstein Condensate form of Ps* can be used to increase the storage density. The long lifetime and high storage density achievable in this device offer utility in several fields, including medicine, materials testing, rocket motors, high power/high energy density storage, gamma-ray lasers, and as an ignition device for initiating nuclear fusion reactions in power plant reactors or hybrid rocket propulsion systems.

Growing community of inventors

Tucson, AZ, United States of America

Nitesh N Shah