Electronic Warfare Support Measures

In military telecommunications, the terms Electronic Support (ES) or Electronic Support Measures (ESM) describe the division of electronic warfare involving actions taken under direct control of an operational commander to detect, intercept, identify, locate, record, and/or analyze sources of radiated electromagnetic energy for the purposes of immediate threat recognition (such as warning that fire control RADAR has locked on a combat vehicle, ship, or aircraft) or longer-term operational planning. Thus, Electronic Support provides a source of information required for decisions involving Electronic Protection (EP), Electronic Attack (EA), avoidance, targeting, and other tactical employment of forces. Electronic Support data can be used to produce signals intelligence (SIGINT), communications intelligence (COMINT) and electronics intelligence (ELINT).

Electronic support measures gather intelligence through passive "listening" to electromagnetic radiations of military interest. Electronic support measures can provide (1) initial detection or knowledge of foreign systems, (2) a library of technical and operational data on foreign systems, and (3) tactical combat information utilizing that library. ESM collection platforms can remain electronically silent and detect and analyze RADAR transmissions beyond the RADAR detection range because of the greater power of the transmitted electromagnetic pulse with respect to a reflected echo of that pulse. United States airborne ESM receivers are designated in the AN/ALR series.

Desirable characteristics for electromagnetic surveillance and collection equipment include (1) wide-spectrum or bandwidth capability because foreign frequencies are initially unknown, (2) wide dynamic range because signal strength is initially unknown, (3) narrow bandpass to discriminate the signal of interest from other electromagnetic radiation on nearby frequencies, and (4) good angle-of arrival measurement for bearings to locate the transmitter. The frequency spectrum of interest ranges from 30 MHz to 50 GHz. Multiple receivers are typically required for surveillance of the entire spectrum, but tactical receivers may be functional within a specific signal strength threshold of a smaller frequency range.

Famous quotes containing the words electronic, warfare, support and/or measures:

    Ideally, advertising aims at the goal of a programmed harmony among all human impulses and aspirations and endeavors. Using handicraft methods, it stretches out toward the ultimate electronic goal of a collective consciousness.
    Marshall McLuhan (1911–1980)

    Insurrection—by means of guerrilla bands—is the true method of warfare for all nations desirous of emancipating themselves from a foreign yoke ... It is invincible, indestructible.
    Giuseppe Mazzini (1805–1872)

    Certainly parents play a crucial role in the lives of individuals who are intellectually gifted or creatively talented. But this role is not one of active instruction, of teaching children skills,... rather, it is support and encouragement parents give children and the intellectual climate that they create in the home which seem to be the critical factors.
    David Elkind (20th century)

    They who have been bred in the school of politics fail now and always to face the facts. Their measures are half measures and makeshifts merely. They put off the day of settlement, and meanwhile the debt accumulates.
    Henry David Thoreau (1817–1862)