The “nervous system” of the military, the collection of subsystems used to maximize situational awareness, is referred to as C4ISR—command, control, communications, computers, intelligence, surveillance, and reconnaissance. The primary objective of a C4ISR system is to present the overall scenario and picture of the area of interest (such as a …

Electromagnetic energy, produced by the vibration of charged particles, travels in the form of waves through the atmosphere and the vacuum of space. These waves have different wavelengths (the distance from wave crest to wave crest) and frequencies, These two are inversely related to each other,  the shorter the wavelength, …