Dual Purpose Laser Range Finder and LIDAR Sensor

The growing number and variety of air and surface targets present a significant challenge for Intelligence, Surveillance, and Reconnaissance systems in areas such as target detection, classification, identification, and tracking. To address this challenge, Systems & Processes Engineering Corporation (SPEC) is developing an eye-safe Dual Purpose Miniature LIDAR and Laser Range Finder, leveraging SPEC’s latest direct-detect LIDAR technology. This system builds upon the company's proven miniature, ruggedized LIDAR product lines, incorporating pseudo-random number encoded pulse burst technology. It is designed to detect targets even through foliage and camouflage nets, and, with target motion, can achieve high-resolution imaging down to 3 mm in cross-range and 1 mm in range. Following a successful Phase I effort, this innovative system represents a major advancement in airborne ISR capabilities, making it suitable for virtually all airborne platforms and missions. SPEC's proposed system uses PRN encoded pulse bursts, offering substantial improvements over previous-generation LIDAR pulse encoding. This technology enhances signal-to-noise ratio by approximately 1000, significantly reducing power consumption while enabling long-range detection with accuracy down to 1 mm (0.040 inches). Additionally, the pulse encoding allows for lower peak power, mitigating issues associated with fiber optic non-linearity. All SPEC direct-detect LIDAR systems operate at 1550 nm, with the electronics and fiber laser integrated into a PCIe104 form factor, incorporating embedded processing for fast image formation. The latest scanner, designed for coherent ranging up to 200 km, uses two sets of double prisms. The front set comprises field-of-regard trackers with a wide field of view and high acceleration, while the rear prisms are field-of-view scanners operating at 10,000 rpm. These prisms are supported by ceramic bearings, with optical encoders attached to the prism barrels to eliminate backlash. This precise prism positioning enables 15.5-bit accuracy. The advanced scanner, with a 3-inch aperture, achieves a range of up to 200 km with LIDAR power levels well below 100 W. In clear conditions (about 23 km of visible seeing), the system's maximum range of 200 km is more than eight times the visual range for a target with 0.1 reflectivity. In 3-km haze, the effective range is 6-7 km. The scanner’s high pointing accuracy allows for laser rangefinder operation by simply aligning the FOV prisms forward and using the FOR prisms for target pointing, achieving a pointing accuracy of 17 micro-radians.