Figure 2-2.—Example of an AREPS radar coverage diagram.

Figure 2-2.—Example of an AREPS radar coverage diagram. As applied to military operations, the term Electro- Optics, or EO, refers to those weapons that require the propagation of electromagnetic energy through the atmosphere for their operation. Although EO systems can operate throughout the entire electromagnetic spectrum, most systems operate in the visible or infrared portions of the spectrum. EO systems are greatly affected by ‘environmental conditions, such as precipitation, haze, and other aerosols. In addition, infrared systems are affected by differences between the temperature of the target and the temperature of the surrounding environment (background). In the early 1980's, computer programs were developed to aid the Aerographer’s Mate in predicting the affects of various environmental parameters on EO systems. The most recent model is known as the Electra-Optical Tactical Decision Aid (EOTDA). EOTDA is a software program whose main function is to predict the performance of air-to-ground weapon systems and direct view optics based on the latest environmental and tactical information. EOTDA supports systems operating in three regions of the electromagnetic spectrum: infrared, visible, and laser. Predictions are based upon meteorological forecasts, target characteristics, the components of the EO system, and tactics. The performance of each system is expressed primarily in terms of maximum detection or lock-on range. Prediction data is displayed in either alphanumeric or graphic format. Figure 2-3 is a sample infrared (IR) visualization display (tank with vegetation background). EOTDA is a DOS-based program contained on floppy disks that can be loaded on virtually any PC. However, it is a large program that requires much hard disk space. Additional hard disk space is required if several generic targets must be created. The EODTA program is outlined in the Electra-Optical Tactical Decision Aid (EOTDA) User’s Manual, prepared by Phillips Laboratory in conjunction with the U.S. Air Force. As of this writing, a Windows NT version of EOTDA is being developed for use with TESS-NC. Keep in mind that the EOTDA software itself is unclassified. When a user adds operational data that makes the output classified, such as times, locations, etc., the user must then take precautions to protect the information at the appropriate level. Appendix B of the Users Manual provides a detailed listing of sensor names, identifications, and classification information. It is classified SECRET and must be ordered separately. You will learn more about the tactical application of electro-optical products in later modules. 2-13