<p>There is a need to remotely measure the full phase and amplitude information of small-scale acousto-seismic vibrations in order to detect the presence of buried objects (e.g., tunnels, etc.), or for other purposes. This remote sensing information may need to be collected with a large area coverage rate and at a safe standoff distance. To accomplish this, we have implemented a shearographic imaging system that incorporates phase stepping in a novel way, automatically separating random speckle noise from surface motion, without requiring an intermediate unwrapping step. This method, which we call surface-phase-resolved shearography, is especially effective for very low-amplitude motions that generate less than one light-wavelength of phase change. In laboratory studies, we have demonstrated sensitivity of two nanometers RMS with 532-nm-wavelength light.</p>
Airborne EO imagery, including wideband, hyperspectral, and multispectral modalities, has greatly enhanced the ability
of the ISR community to detect and classify various targets of interest from long standoff distances and with large area
coverage rates. The surf zone is a dynamic environment that presents physical and operational challenges to effective
remote sensing with optical systems. In response to these challenges, BAE Systems has developed the Tactical Multi-spectral
(TACMSI) system. The system includes a VNIR six-band multispectral sensor and all other hardware that is
used to acquire, store and process imagery, navigation, and supporting metadata on the airborne platform. In
conjunction with the hardware, BAE Systems has innovative data processing methods that exploit the inherent
capabilities of multi-look framing imagery to essentially remove the overlying clutter or obscuration to enable EO
visualization of the objects of interest.
Airborne surveillance presents challenging target-detection opportunities for optical remote sensors, especially under the constraints of size, weight, and power imposed by small aircraft. We present a spatial-frequency dependent figure-of-merit, called the Detector Quantum Efficiency (DQE), by first tracing its origins in single pixel photon multiplication detectors, where it is shown to be yield (quantum efficiency or QE) divided by the noise factor. We then show the relationship of DQE to several well-known figures-of-merit. Finally we broaden the definition of DQE to include the spatial-frequency dependence on the MTF of the system and the noise power spectrum (NPS) of the detector. We then present the results of the application of this DQE to a hyperspectral camera under development at BAE Systems Spectral Solutions LLC.
The design, operation, and performance of the fourth generation of Science and Technology International's Advanced Airborne Hyperspectral Imaging Sensors (AAHIS) are described. These imaging spectrometers have a variable bandwidth ranging from 390-840 nm. A three-axis image stabilization provides spatially and spectrally coherent imagery by damping most of the airborne platform's random motion. A wide 40-degree field of view coupled with sub-pixel detection allows for a large area coverage rate. A software controlled variable aperture, spectral shaping filters, and high quantum efficiency, back-illuminated CCD's contribute to the excellent sensitivity of the sensors. AAHIS sensors have been operated on a variety of fixed and rotary wing platforms, achieving ground-sampling distances ranging from 6.5 cm to 2 m. While these sensors have been primarily designed for use over littoral zones, they are able to operate over both land and water. AAHIS has been used for detecting and locating submarines, mines, tanks, divers, camouflage and disturbed earth. Civilian applications include search and rescue on land and at sea, agricultural analysis, environmental time-series, coral reef assessment, effluent plume detection, coastal mapping, damage assessment, and seasonal whale population monitoring