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Ormesher, Richard C.

Publications and source records attributed to Ormesher, Richard C..

Doppler-assisted sensor fusion

Various technologies for identifying RF emitters in geolocation datasets are described herein. Doppler signatures of RF emitters and geolocation data of objects in a scene are collected simultaneously, then range-rate profiles of the movement of the RF emitters and the objects in the scene are computed. An RF emitter is identified in a geolocation dataset by comparing the motion of the RF emitter with the motion of an object in the scene as described by the respective range-rate profiles.

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Artifact reduction within a SAR image

The various technologies presented herein relate to reducing and/or filtering undesired artifacts in a SAR image, wherein the artifacts are generated by RF interference resulting from a communication signal being included in a radar return which also comprises radar clutter. The radar return is separated into two subapertures, a first subaperture comprising radar clutter only, and a second subaperture comprising radar clutter and the communication signal. The communication signal is extracted from the second subaperture and reapplied to the initially received radar return. Reapplication of the communication signal to the radar return enables any undesired artifacts arising from the communication signal to have their return strength reduced or minimized, while maintaining any desired radar returns in the SAR image.

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Subaperture clutter filter with CFAR signal detection

The various technologies presented herein relate to the determination of whether a received signal comprising radar clutter further comprises a communication signal. The communication signal can comprise of a preamble, a data symbol, communication data, etc. A first portion of the radar clutter is analyzed to determine a radar signature of the first portion of the radar clutter. A second portion of the radar clutter can be extracted based on the radar signature of the first portion. Following extraction, any residual signal can be analyzed to retrieve preamble data, etc. The received signal can be based upon a linear frequency modulation (e.g., a chirp modulation) whereby the chirp frequency can be determined and the frequency of transmission of the communication signal can be based accordingly thereon. The duration and/or bandwidth of the communication signal can be a portion of the duration and/or the bandwidth of the radar clutter.

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