The development, integration and testing of a compact system for wide-area persistence surveillance in dedicated
maritime environments is presented. The system is based around a large-format, 2560 x 512 pixel focal plane array,
high dynamic range (16 bit), mid-wave infrared (MWIR) imager operating at 30 Hz that is equipped with a 90°
horizontal field-of-view (HFOV) lens. The digitized image data is fed to a standard commercial-off-the-shelf (COTS)
workstation equipped with a graphical processing unit (GPU) that is used to perform image de-warping, non-uniformity
corrections, and algorithms for real-time object detection and tracking (NRL Harbor Tracking Software-NRLHaTS). Data is presented from several field experiments that illustrate the capabilities of the integrated system.
This work offers a comparison of broadband shortwave infrared, defined as the spectral band from 0.9 to 1.7 μm, and hyperspectral shortwave infrared imagers in a marine environment under various daylight conditions. Both imagers are built around a Raytheon Vision Systems large format (1024×1280) indium-gallium-arsenide focal plane array with high dynamic range and low noise electronics. Sample imagery from a variety of objects and scenes indicates roughly the same visual performance between the two systems. However, we show that the more detailed spectral information provided by the hyperspectral system allows for object detection and discrimination. A vessel was equipped with panels coated with a variety of paints that possessed spectral differences in the 0.9 to 1.7 μm waveband. The vessel was imaged at various ranges, states of background clutter, and times of the day. Using a standard correlation receiver, it is demonstrated that image pixels containing the paint can be easily identified. During the exercise, it was also observed that both bow waves and near-field wakes from a wide variety of vessel traffic provide a spectral signature in the shortwave infrared waveband that could potentially be used for object tracking.
The U.S. Naval Research Laboratory (NRL) established a one-way Gigabit Ethernet lasercomm link during the
Seahawk exercise in August, 2007 to transfer data ~8 miles across the inlet of San Diego Bay from Point Loma to
the Imperial Beach base camp. The data transferred over the link was from an NRL developed, wide field of view
(90 degrees), high resolution, mid-wave infrared camera operating at 30 frames per second. Details of the high
speed link will be presented as well as packet error rate data and atmospheric propagation data taken during the two
week long exercise.