The ASL is at the forefront of the development of modulated polarimeters. These are devices that use polarization optics that vary in time, space, or wavelength in order to introduce polzarization-dependent modulation into the intensity. The polarization information can then be extracted from side lobes created in frequency space, and the sensor resolution can be optimized in the various domains. This work is carried out in collaboration with the Sensors Directorate of AFRL, the Polarization Lab, Polaris Sensor Technologies and has been funded by AFOSR, AFRL, NASA, and various SBIR partnerships.

Polarimetric imaging in the LWIR presents some specific challenges that are not faced in other wave bands. The underlying sensors are harder to calibrate and more expensive to operate, and hence the polarimeters are that much more difficult to use. The ASL works on novel hardware- and software-based calibration methods that are ideally suited to LWIR polarization data, especially in regards to microgrid polarimeters. This work has been funded by AFOSR and AFRL.

Tropical cyclones – a. k. a. hurricanes in the Atlantic Ocean or Typhoons in the NW Pacific Ocean – spend most of their lives over the open ocean. During these times, it is extremely expensive to obtain in situ measurements of the storm parameters, and forecasters must rely on numerical models and estimation methods. One area that is especially challenging is the objective estimation of cyclone intensity. The ASL has collaborated with the Hurricane Lab to develop a unique, objective estimation method that determines intensity from symmetry parameters in IR imagery. The method is especially useful at low intensities, and has been shown to improve both the accuracy and detection time of tropical depressions. The work is currently funded by the National Oceanographic Partnership Program, and we collaborate with the National Hurricane Center, Naval Research Lab, and the Joint Typhoon Warning Center.

The ASL has partnered with ASR Corporation under funding from several SBIR and STTR awards from the Army and Air Force to develop compact, high power microwave sources. The sources we have developed are mesoband switched oscillators that can but out 10s of MW of power in bursts of several tens of nanoseconds.

One of the challenges in HPM is the development of antenna technologies that can handle extremely large input powers at low frequencies (< 100 MHz), yet can still fit into compact platforms. ASL researchers have partnered with ASR Corporation and Prof. Rick Ziolkowski’s Casa de Creative Electromagnetics to develop a range of antenna options for both self-resonant and driven applications.

ASL researchers collaborate with the Directed Energy Directorate of AFRL, Advanced Optical Technologies, and the French Institut d’Optique to develop theory and algorithms for exploiting polarimetric scattering information in active polarimeters. By understanding how the different elements of the Mueller matrix relate to specific detection tasks, we are able to develop simpler, lower-cost polarimeters. This work has been funded by AFOSR and SBIR awards from the US Army.

ASL researchers are develop novel computational imagery methods that can extract information about a scene – spectral, depth, polarization, coherence, etc. – by tricking the camera and reconstructing in post-processing. Our particular interest areas are non-stereo depth imaging and plenoptic spectrometrs and polarimeters.

ASL researchers are working with TeraVision, LLC, and the Steward Observatory to develop short-range imaging radars in the THz and mm-wave radio bands. THz imagers provide reasonable resolution and can penetrate many materials that are optically opaque. ASL focuses on the calibration and data reconstruction algorithms. The work is currently supported by the National Consortium for MASINT Research.

ASL Researchers are developing new, high-order pattern recognition algorithms that can be used to extract physically meaningful features from high-dimensional remote sensing data. We collaborate with the Hurricane Lab to apply these tools to tropical cyclone forecasting problems. The work has been funded by the National Science Foundation.

ASL researchers are investigating optimal Polarimetric Display techniques. The addition of polarization imaging to the S₀ channel containing thermal or visible information presents new challenges in information presentation. The project is currently exploring two methods for "fusing" this information. The first method uses color fusion based on the average color perception of the human visual system. The other method uses motion for cases where the observer is color blind. ASL researchers seek to optimize the presentation of the polarization information against the behaviors of the human visual system through such techniques as mapping orthogonal polarization states to the most diverse possible human visual components.