Jamming Signals

Jamming signals are deliberate electromagnetic (EM) transmissions of random noise or other signals that are emitted with the intention of disrupting the flow of information in electromagnetic sensor systems, and in command, control, communications, and intelligence (C3I) systems. Jamming describes a subset of activities from the field of electronic warfare (EW), and a jammer is the transmitter producing the jamming signal. This entry describes the types and uses of jamming signals by military forces.

Early low-power amplitude modulation (AM) radios had difficulty reliably discerning valid signals in an EM environment because of the natural noise present in the environment and the noise produced by their crude components. With improvements, dependence on long-range radio communications increased, and military radio experts came to recognize the benefit of obstructing ...