Radiofrequency MASINT
Encyclopedia
Radiofrequency MASINT is one of the six major disciplines generally accepted to make up the field of Measurement and Signature Intelligence
(MASINT), with due regard that the MASINT subdisciplines may overlap, and MASINT, in turn, is complementary to more traditional intelligence collection and analysis disciplines such as SIGINT and IMINT
. MASINT encompasses intelligence gathering activities that bring together disparate elements that do not fit within the definitions of Signals Intelligence (SIGINT), Imagery Intelligence (IMINT), or Human Intelligence
(HUMINT).
According to the United States Department of Defense
, MASINT is technically derived intelligence (excluding traditional imagery IMINT
and signals intelligence SIGINT) that – when collected, processed, and analyzed by dedicated MASINT systems – results in intelligence that detects, tracks, identifies, or describes the signatures (distinctive characteristics) of fixed or dynamic target sources. MASINT was recognized as a formal intelligence discipline in 1986. See Measurement and Signature Intelligence
for an overview of the discipline and its unifying principles. As with many branches of MASINT, specific techniques may overlap with the six major conceptual disciplines of MASINT defined by the Center for MASINT Studies and Research, which divides MASINT into Electro-optical, Nuclear, Geophysical, Radar, Materials, and Radiofrequency disciplines.
, IMINT
, and SIGINT. To be more confusing, while MASINT is highly technical and is called such, TECHINT
is another discipline, dealing with such things as the analysis of captured equipment.
An example of the interaction is "imagery-defined MASINT (IDM)". In IDM, a MASINT application would measure the image, pixel
by pixel, and try to identify the physical materials, or types of energy, that are responsible for pixels or groups of pixels: signatures. When the signatures are then correlated to precise geography, or details of an object, the combined information becomes something greater than the whole of its IMINT and MASINT parts.
The Center for MASINT Studies and Research
breaks MASINT into:
Where COMINT and ELINT, the two major components of SIGINT, focus on the intentionally transmitted part of the signal, radiofrequency MASINT focuses on unintentionally transmitted information. For example, a given radar antenna will have sidelobes emanating from other than the direction in which the main antenna is aimed. The RADINT (radar intelligence) MASINT subdiscipline involves learning to recognize a radar both by its primary signal, captured by ELINT, and its sidelobes, perhaps captured by the main ELINT sensor, or, more likely, a sensor aimed at the sides of the radio antenna.
MASINT associated with COMINT might involve the detection of common background sounds expected with human voice communications. For example, if a given radio signal comes from a radio used in a tank, if the interceptor does not hear engine noise or higher voice frequency than the voice modulation
usually uses, even though the voice conversation is meaningful, MASINT might suggest it is a deception, not coming from a real tank.
See HF/DF for a discussion of SIGINT-captured information with a MASINT flavor, such as determining the frequency to which a receiver is tuned, from detecting the frequency of the beat frequency oscillator of the superheterodyne receiver. This may also be considered unintentional RF radiation (RINT). The local oscillator intercept technique, Operation RAFTER
was first made public by a book by a retired senior officer in Britain's counterintelligence service, MI5
. The book also discusses acoustic methods of capturing COMINT.
For example, in a program called BURNING LIGHT, KC-135R tankers, temporarily modified to carry MASINT sensors, would fly around the test area, as part of Operation BURNING LIGHT. One sensor system measured the electromagnetic pulse
of the detonation.
While EMP often is assumed to be a characteristic of nuclear weapons alone, such is not the case. Several open-literature techniques, requiring only conventional explosives, or, in the case of high power microwave, a large electrical power supply, perhaps one-shot as with capacitors, can generate a significant EMP:
EMP intelligence deals both offensive capability to build, generate particular power vs. frequency spectra, and means of optimizing coupling or other power delivery, and defensive EMP considerations of vulnerability.
Vulnerability has two components:
Another aspect of offensive EMP intelligence is to evaluate the ways in which an EMP weapon could improve coupling. One approach involves the device extruding antennas. Another, similar to other precision guided munitions, is to bring the device as close as possible to the target.
Intelligence about EMP defense would consider the deliberate use of shielding (e.g., Faraday cages) or greater use of optical cabling.
, which listened for the direct or additive frequency of the local oscillator
in a superheterodyne receiver
.
This technique can be countered by shielding the intermediate frequency circuitry of superheterodyne receivers, or moving into software-defined radio
using digital signal processor
s with no local oscillator.
is an unclassified US code word for the set of techniques for securing equipment from eavesdropping on Van Eck radiation and other emanations.
One of the blurry areas, for example, is understanding the normal incidental radiation from something as basic as a television set. The signals of a consumer product such as that are sufficiently complex that it may be practical to hide a covert eavesdropping channel within it.
For example, in 1952, the Soviets presented the US Moscow embassy with a beautiful Great Seal of the United States. The Seal, however, had an acoustic diaphragm, forming a side of a resonant cavity which, when illuminated with a microwave beam, reflected the beam back as a signal that was modulated by the audio of conversations in the room. The conversations caused the dimensions of the resonant cavity to change, producing the modulated signal, This was a Passive Resonant Cavity Bug.
This effect may not require a purpose-built modulator. Items as mundane as an incandescent light bulb may act as modulators.
TEAPOT, assuming that is the code name, has similarities to the technique of using the reflections of a laser from a window. In that technique, the window vibrates from acoustic pressure on the inside, and modulates the laser carrier.
signals, by detecting signals of greater amplitude than the expected electrical ground. In an unbalanced transmission, the ground serves as a signal reference.
between the RED and BLACK signals.
HIJACK is a more advanced threat, where the RED signal modulates a RF signal generated within the secure area, such as a cellular telephone. While HIJACK targets RF, NONSTOP targets the pulses of a digital device, typically a computer.
Measurement and Signature Intelligence
Measurement and signature intelligence is a branch of intelligence gathering activities.MASINT, may have aspects of intelligence analysis management, since certain aspects of MASINT, such as the analysis of electromagnetic radiation received by signals intelligence are more of an analysis...
(MASINT), with due regard that the MASINT subdisciplines may overlap, and MASINT, in turn, is complementary to more traditional intelligence collection and analysis disciplines such as SIGINT and IMINT
IMINT
Imagery Intelligence , is an intelligence gathering discipline which collects information via satellite and aerial photography. As a means of collecting intelligence, IMINT is a subset of intelligence collection management, which, in turn, is a subset of intelligence cycle management...
. MASINT encompasses intelligence gathering activities that bring together disparate elements that do not fit within the definitions of Signals Intelligence (SIGINT), Imagery Intelligence (IMINT), or Human Intelligence
HUMINT
HUMINT, a syllabic abbreviation of the words HUMan INTelligence, refers to intelligence gathering by means of interpersonal contact, as opposed to the more technical intelligence gathering disciplines such as SIGINT, IMINT and MASINT...
(HUMINT).
According to the United States Department of Defense
United States Department of Defense
The United States Department of Defense is the U.S...
, MASINT is technically derived intelligence (excluding traditional imagery IMINT
IMINT
Imagery Intelligence , is an intelligence gathering discipline which collects information via satellite and aerial photography. As a means of collecting intelligence, IMINT is a subset of intelligence collection management, which, in turn, is a subset of intelligence cycle management...
and signals intelligence SIGINT) that – when collected, processed, and analyzed by dedicated MASINT systems – results in intelligence that detects, tracks, identifies, or describes the signatures (distinctive characteristics) of fixed or dynamic target sources. MASINT was recognized as a formal intelligence discipline in 1986. See Measurement and Signature Intelligence
Measurement and Signature Intelligence
Measurement and signature intelligence is a branch of intelligence gathering activities.MASINT, may have aspects of intelligence analysis management, since certain aspects of MASINT, such as the analysis of electromagnetic radiation received by signals intelligence are more of an analysis...
for an overview of the discipline and its unifying principles. As with many branches of MASINT, specific techniques may overlap with the six major conceptual disciplines of MASINT defined by the Center for MASINT Studies and Research, which divides MASINT into Electro-optical, Nuclear, Geophysical, Radar, Materials, and Radiofrequency disciplines.
Disciplines
MASINT is made up of six major disciplines, but the disciplines overlap and intertwine. They interact with the more traditional intelligence disciplines of HUMINTHUMINT
HUMINT, a syllabic abbreviation of the words HUMan INTelligence, refers to intelligence gathering by means of interpersonal contact, as opposed to the more technical intelligence gathering disciplines such as SIGINT, IMINT and MASINT...
, IMINT
IMINT
Imagery Intelligence , is an intelligence gathering discipline which collects information via satellite and aerial photography. As a means of collecting intelligence, IMINT is a subset of intelligence collection management, which, in turn, is a subset of intelligence cycle management...
, and SIGINT. To be more confusing, while MASINT is highly technical and is called such, TECHINT
Techint
Techint is a conglomerate multinational company founded in Milan in September 1945 by Italian industrialist Agostino Rocca and headquartered in Milan and Buenos Aires . Techint comprises more than 100 companies operating worldwide in the following areas of business: Engineering & Construction,...
is another discipline, dealing with such things as the analysis of captured equipment.
An example of the interaction is "imagery-defined MASINT (IDM)". In IDM, a MASINT application would measure the image, pixel
Pixel
In digital imaging, a pixel, or pel, is a single point in a raster image, or the smallest addressable screen element in a display device; it is the smallest unit of picture that can be represented or controlled....
by pixel, and try to identify the physical materials, or types of energy, that are responsible for pixels or groups of pixels: signatures. When the signatures are then correlated to precise geography, or details of an object, the combined information becomes something greater than the whole of its IMINT and MASINT parts.
The Center for MASINT Studies and Research
breaks MASINT into:
- Electro-optical MASINTElectro-optical MASINTElectro-optical MASINT is a subdiscipline of Measurement and Signature Intelligence, and refers to intelligence gathering activities which bring together disparate elements that do not fit within the definitions of Signals Intelligence , Imagery Intelligence , or Human Intelligence...
- Nuclear MASINTNuclear MASINTNuclear MASINT is one of the six major subdisciplines generally accepted to make up Measurement and Signature Intelligence , which covers measurement and characterization of information derived from nuclear radiation and other physical phenomena associated with nuclear weapons, reactors, processes,...
- Geophysical MASINTGeophysical MASINTGeophysical MASINT is a branch of Measurement and Signature Intelligence that involves phenomena transmitted through the earth and manmade structures including emitted or reflected sounds, pressure waves, vibrations, and magnetic field or ionosphere disturbances.According to the United States...
- Radar MASINTRadar MASINTRadar MASINT is one of the subdisciplines of Measurement and Signature Intelligence and refers to intelligence gathering activities that bring together disparate elements that do not fit within the definitions of Signals Intelligence , Imagery Intelligence , or Human Intelligence...
- Materials MASINTMaterials MASINTMaterials MASINT is one of the six major disciplines generally accepted to make up the field of Measurement and Signature Intelligence , with due regard that the MASINT subdisciplines may overlap, and MASINT, in turn, is complementary to more traditional intelligence collection and analysis...
Where COMINT and ELINT, the two major components of SIGINT, focus on the intentionally transmitted part of the signal, radiofrequency MASINT focuses on unintentionally transmitted information. For example, a given radar antenna will have sidelobes emanating from other than the direction in which the main antenna is aimed. The RADINT (radar intelligence) MASINT subdiscipline involves learning to recognize a radar both by its primary signal, captured by ELINT, and its sidelobes, perhaps captured by the main ELINT sensor, or, more likely, a sensor aimed at the sides of the radio antenna.
MASINT associated with COMINT might involve the detection of common background sounds expected with human voice communications. For example, if a given radio signal comes from a radio used in a tank, if the interceptor does not hear engine noise or higher voice frequency than the voice modulation
Modulation
In electronics and telecommunications, modulation is the process of varying one or more properties of a high-frequency periodic waveform, called the carrier signal, with a modulating signal which typically contains information to be transmitted...
usually uses, even though the voice conversation is meaningful, MASINT might suggest it is a deception, not coming from a real tank.
Frequency Domain MASINT
Different from emitter location in SIGINT, frequency analysis MASINT concentrates not on finding a specific device, but on characterizing the signatures of a class of devices, based on their intentional and unintentional radio emissions. Devices being characterized could include radars, communication radios, radio signals from foreign remote sensors, radio frequency weapons (RFW), collateral signals from other weapons, weapon precursors, or weapon simulators (for example, electromagnetic pulse signals associated with nuclear bursts); and spurious or unintentional signals.See HF/DF for a discussion of SIGINT-captured information with a MASINT flavor, such as determining the frequency to which a receiver is tuned, from detecting the frequency of the beat frequency oscillator of the superheterodyne receiver. This may also be considered unintentional RF radiation (RINT). The local oscillator intercept technique, Operation RAFTER
Operation RAFTER
RAFTER was a code name for the MI5 radio receiver detection technique, mostly used against clandestine Soviet agents and monitoring of domestic radio transmissions by foreign embassy personnel from the 1950s on.- Explanation :...
was first made public by a book by a retired senior officer in Britain's counterintelligence service, MI5
MI5
The Security Service, commonly known as MI5 , is the United Kingdom's internal counter-intelligence and security agency and is part of its core intelligence machinery alongside the Secret Intelligence Service focused on foreign threats, Government Communications Headquarters and the Defence...
. The book also discusses acoustic methods of capturing COMINT.
Electromagnetic Pulse MASINT
Nuclear and large conventional explosions produce radio frequency energy. The characteristics of the EMP will vary with altitude and burst size. EMP-like effects are not always from open-air or space explosions; there has been work with controlled explosions for generating electrical pulse to drive lasers and railguns.For example, in a program called BURNING LIGHT, KC-135R tankers, temporarily modified to carry MASINT sensors, would fly around the test area, as part of Operation BURNING LIGHT. One sensor system measured the electromagnetic pulse
Electromagnetic pulse
An electromagnetic pulse is a burst of electromagnetic radiation. The abrupt pulse of electromagnetic radiation usually results from certain types of high energy explosions, especially a nuclear explosion, or from a suddenly fluctuating magnetic field...
of the detonation.
While EMP often is assumed to be a characteristic of nuclear weapons alone, such is not the case. Several open-literature techniques, requiring only conventional explosives, or, in the case of high power microwave, a large electrical power supply, perhaps one-shot as with capacitors, can generate a significant EMP:
- Explosively pumped flux compression generatorExplosively pumped flux compression generatorAn explosively pumped flux compression generator is a device used to generate a high-power electromagnetic pulse by compressing magnetic flux using high explosive....
s (FCG) - Explosive and Propellant Driven MHD Generators
- High Power Microwave Sources - Spark gapSpark gapA spark gap consists of an arrangement of two conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the voltage difference between the conductors exceeds the gap's breakdown voltage, a spark forms,...
s or the VircatorVircatorA vircator is a microwave generator that is capable of generating brief pulses of tunable, narrow band microwaves at very high power levels....
EMP intelligence deals both offensive capability to build, generate particular power vs. frequency spectra, and means of optimizing coupling or other power delivery, and defensive EMP considerations of vulnerability.
Vulnerability has two components:
- Coupling modes possible between the EMP source and the equipment
-
-
- Front door coupling goes through an antenna intended to receive power in the frequency range being generated
- Back door coupling in which the EMP produces surges in power (including ground) and communications wire.
- The level of energy coupled that will damage or destroy a particular target.
-
Another aspect of offensive EMP intelligence is to evaluate the ways in which an EMP weapon could improve coupling. One approach involves the device extruding antennas. Another, similar to other precision guided munitions, is to bring the device as close as possible to the target.
Intelligence about EMP defense would consider the deliberate use of shielding (e.g., Faraday cages) or greater use of optical cabling.
Unintentional Radiation MASINT
The integration and specialized application of MASINT techniques against unintentional radiation sources (RINT) that are incidental to the RF propagation and operating characteristics of military and civil engines, power sources, weapons systems, electronic systems, machinery, equipment, or instruments. These techniques may be valuable in detecting, tracking, and monitoring a variety of activities of interest.Black Crow: truck detection on the Ho Chi Minh trail
A Vietnam-era "Black Crow" RINT sensor, carried aboard AC-130 gunships, detected the "static" produced by the ignition system of trucks on the Ho Chi Minh trail, from distances up to 10 miles, and cue weapons onto the truck.Monitoring potentially necessary electronic emissions
Yet another technique that could determine the frequency to which a receiver is tuned was the technique of Operation RAFTEROperation RAFTER
RAFTER was a code name for the MI5 radio receiver detection technique, mostly used against clandestine Soviet agents and monitoring of domestic radio transmissions by foreign embassy personnel from the 1950s on.- Explanation :...
, which listened for the direct or additive frequency of the local oscillator
Local oscillator
A local oscillator is an electronic device used to generate a signal normally for the purpose of converting a signal of interest to a different frequency using a mixer. This process of frequency conversion, also referred to as heterodyning, produces the sum and difference frequencies of the...
in a superheterodyne receiver
Superheterodyne receiver
In electronics, a superheterodyne receiver uses frequency mixing or heterodyning to convert a received signal to a fixed intermediate frequency, which can be more conveniently processed than the original radio carrier frequency...
.
This technique can be countered by shielding the intermediate frequency circuitry of superheterodyne receivers, or moving into software-defined radio
Software-defined radio
A software-defined radio system, or SDR, is a radio communication system where components that have been typically implemented in hardware are instead implemented by means of software on a personal computer or embedded computing devices...
using digital signal processor
Digital signal processor
A digital signal processor is a specialized microprocessor with an architecture optimized for the fast operational needs of digital signal processing.-Typical characteristics:...
s with no local oscillator.
Unintentional radiation from electronic devices
This discipline blurs into the various techniques for collecting COMINT from unintentional radiation, both electromagnetic and acoustic, from electronic devices. TEMPESTTEMPEST
TEMPEST is a codename referring to investigations and studies of compromising emission . Compromising emanations are defined as unintentional intelligence-bearing signals which, if intercepted and analyzed, may disclose the information transmitted, received, handled, or otherwise processed by any...
is an unclassified US code word for the set of techniques for securing equipment from eavesdropping on Van Eck radiation and other emanations.
One of the blurry areas, for example, is understanding the normal incidental radiation from something as basic as a television set. The signals of a consumer product such as that are sufficiently complex that it may be practical to hide a covert eavesdropping channel within it.
Covert modulators for audio surveillance
Another category, to which the US code name TEAPOT may apply, is the detection not simply of RF, but of an unintended audio modulation of an external RF signal flooding the area being surveilled. Some object within the room acoustically couples to sound in the room, and acts as a modulator. The group doing the covert surveillance examines the reflected RF for amplitude modulation at the original frequency, or across a spectral band for frequency modulationFor example, in 1952, the Soviets presented the US Moscow embassy with a beautiful Great Seal of the United States. The Seal, however, had an acoustic diaphragm, forming a side of a resonant cavity which, when illuminated with a microwave beam, reflected the beam back as a signal that was modulated by the audio of conversations in the room. The conversations caused the dimensions of the resonant cavity to change, producing the modulated signal, This was a Passive Resonant Cavity Bug.
This effect may not require a purpose-built modulator. Items as mundane as an incandescent light bulb may act as modulators.
TEAPOT, assuming that is the code name, has similarities to the technique of using the reflections of a laser from a window. In that technique, the window vibrates from acoustic pressure on the inside, and modulates the laser carrier.
Secure signal leakage into ground
As early as the First World War, it was possible to intercept the information content of a telegraph or telephone using electrically unbalancedUnbalanced
Unbalanced may refer to:* Unbalanced line or network in electrical circuits, where the impedance of the two conductor paths are not equal* An unbalanced formation in American football* Unbalanced chemical equations...
signals, by detecting signals of greater amplitude than the expected electrical ground. In an unbalanced transmission, the ground serves as a signal reference.
Covert modulation for digital surveillance
In the 1950s, it was found that there could be electrical coupling between the unencrypted side of a "RED" signal inside a secure communications facility, and either the conductor carrying the "BLACK" encrypted signal, or possibly the electrical ground(s) of the system. TEMPEST protective measures work against the situation when the frequency of the RED and BLACK signals are the same. The RED signal, at a low power level, may be intercepted directly, or there may be intermodulationIntermodulation
Intermodulation or intermodulation distortion is the amplitude modulation of signals containing two or more different frequencies in a system with nonlinearities...
between the RED and BLACK signals.
HIJACK is a more advanced threat, where the RED signal modulates a RF signal generated within the secure area, such as a cellular telephone. While HIJACK targets RF, NONSTOP targets the pulses of a digital device, typically a computer.