Scanning electro-optic (e/o) systems are currently being developed for installation in surface ships. These electro-optic systems can provide accurate angular position data on objects that are being viewed but do not provide range to the objects. Under conditions of total passive surveillance (e.g. When active radar sensors are shut down) surface operations must be performed without range information. This can be extremely hazardous. The only alternative is to turn on active sensors and risk disclosure of own ships presence and position to hostile units, and exposure to attack by anti-radiation weapons. Synertech proposes to examine techniques for passive ranging and to develop an algorithm that will allow surface ship to have a tactical option to effectively operate during periods when radio frequency emissions are being controlled. This will be done by examining the performance of several methods of passive ranging and quantifying their capabilities and limitations under a variety of operational and environmental conditions. An optimum passive ranging algorithm will be developed, evaluated and prepared for implementation on a general purpose computer.
