A High-Resolution Unconventional Imager for Missile Defense Applications.
Abstract
During this reporting period a detailed MathCAD-based ASI signal performance model was completed and checked. Also, the laser energy requirements were estimated for the three potential ASI military applications reported last period. The results were discouragingly high, ranging from 35 Joules to 135 Joules per pulse. (The laser pulses N times to collect an N x N pixel image.) This led to a careful analysis of tradeoffs affecting transmit energy requirements. A significant understanding resulted: the ASI imager works extremely well (from a laser energy point of view) when very small objects like missiles or space debris are imaged over large distances. Also. laser energy requirements decrease when the transmitter wavelength is increased. In each case the smallest speckle lobe increases in size. and more photons are collected as the subaperture size is scaled accordingly. Interestingly. this suggests that ASI can fill a very unique niche where radar cannot supply the spatial resolution and conventional optics are too bulky and expensive to perform long-range non-cooperative target identification of small targets. Hence ASI may be "the only game in town" as an adjunct sensor for Patriot missile batteries, as a non-cooperative target I.D. sensor on fighter aircraft protecting a Navy carrier group or as a space debris imager protecting the space shuttle or space station.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1995
- Accession Number
- ADA300044