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 Aerographers 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.
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
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) Users 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.