Multi-spectral camouflage is the use of counter-surveillance techniques to conceal objects from detection across several parts of the electromagnetic spectrum at the same time. While traditional military camouflage attempts to hide an object in the visible spectrum, multi-spectral camouflage also tries to simultaneously hide objects from detection methods such as infrared, radar, and millimetre-wave radar imaging.[1][2]

German Marder 1A5 with Saab Barracuda mobile multi-spectral camouflage

Among animals, both insects such as the eyed hawk-moth, and vertebrates such as tree frogs possess camouflage that works in the infra-red as well as in the visible spectrum.

History

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The caterpillar of the eyed hawk-moth Smerinthus ocellatus is camouflaged to match a leafy background in both visible and infra-red light.

The English zoologist Hugh Cott, in his 1940 book Adaptive Coloration in Animals, wrote that some caterpillars such as the eyed hawk-moth Smerinthus ocellatus, and tree frogs such as the red-snouted treefrog Hyla coerulea, are coloured so as to blend with their backgrounds whether observed in visible light or in infra-red.[3][4] Cott noted the importance of camouflage in the infra-red, given the ability of tactical reconnaissance to observe in this part of the spectrum:

Because such screens are effective against direct observation and ordinary photography, by no means does it follow that they will be hidden in the infra-red photograph. Comparison of aerial photographs taken simultaneously on panchromatic and infra-red plates will reveal much that before the advent of this new technique would have been adequately camouflaged...

— Hugh Cott, 1940.[5]

A German-led NATO research project concluded in 2004 that while "the multispectral signatures of most military equipment can be significantly reduced by combinations of various camouflage materials", multi-spectral camouflage for individual soldiers remained lacking. The main problems identified were operational constraints such as mobility, weight, and the soldier's physiology.[6]

Camouflage

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Multi-spectral camouflage can be applied to individuals, to vehicles, and to buildings. It can take the form of specialised paints or camouflage nets that provide conventional camouflage, reduce the amount of heat given off by an object, and alter the shape and size of its radar signature.[7][8][9][10][11][12] The Saab Barracuda Mobile Camouflage System provides a degree of concealment in the visible, thermal infrared, and radar parts of the electromagnetic spectrum,[13] as does the Miranda Berberys-R multispectral camouflage system from Poland.[14] Similarly, other companies such as the American-Israeli "Fibrotex" and "Ametrine", and the Greek "Intermat Defence" proposed their own products ranging from static vehicle camouflage fabric to multispectral spray paints.

 
An example of individual multispectral camouflage. The showcased suit provides simultaneous camouflage in the VIS and LWIR wavelengths of the electromagnetic spectrum. The soldier thermal signature matches the surrounding environment. Credits: ProApto Camouflage

Saab AB began offering a multi-spectral personal camouflage system known as the Special Operations Tactical Suit (SOTACS) as early as 2005.[15] And as of 2018, multiple countries are phasing out legacy camouflage systems with multi-spectral systems.[16][17]

In 2024, IIT Kanpur introduced Anālakṣhya, a Meta-material Surface Cloaking System (MSCS). The Meta-material Microwave Absorber improves stealth capabilities against Synthetic Aperture Radar (SAR) imaging by wave absorption across a wide spectrum.[18][19] In the last decade other companies developed their own individual multispectral camouflage, such as the Israeli "Polaris Solutions", the American "Relv Camo", and the Italian "ProApto". The latter specifically focuses on 3D individual camouflage, proposing multispectral Ghillie Suits designed also for amphibious operations and both tropical and arctic environments.

Examples across the electromagnetic spectrum

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Electromagnetic spectrum[20]
Name Wavelength Detected by Camouflage Technology Example application
Ultraviolet 10 nm – 380 nm
Visible light 380 nm – 700 nm Eyes, cameras Paint, nets, counter-illumination Uniforms
Shorter Infrared 700 nm – 3 μm Image intensifiers
Mid or Thermal infrared 3 μm – 8 μm Heat-seeking missile
Long infrared 8 μm – 15 μm Thermal imaging sensor Peltier cooling plates Adaptiv
Far infrared 15 μm – 1 mm
Microwave 1 mm – 1 m Radar Stealth technology Northrop Grumman B-2 Spirit, F-117 Nighthawk
Longer Radio waves 1 m – 100,000 km

Problems

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As this type of camouflage hinders electromagnetic radiation, radio-communications and GPS are also hindered. This can be overcome by using frequency selective surfaces, allowing specific frequencies to pass through.[21]

See also

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References

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  1. ^ Shabbir, Usman. "Highlights from IDEAS 2002". ACIG Special Reports. Air Combat Information Group. Retrieved 30 April 2013.
  2. ^ A US 4287243 A, Nielsen, Willi G., "Mat for multispectral camouflage of objects and permanent constructions", published Sep 1, 1981 
  3. ^ Ramana Rao, J.V. "Introduction to Camouflage & Deception" (PDF). Defence Research and Development Organisation (India). p. 116. Retrieved 13 June 2014.
  4. ^ Cott, Hugh B. (1940). Adaptive Coloration in Animals. Oxford University Press. p. Plate 5 shows the eyed hawk-moth caterpillar in visible and infra-red on a leafly background; Plate 6 shows a tree-frog similarly. It is clear from the plates that these animals reflect infra-red.
  5. ^ Cott, Hugh B. (1940). Adaptive Coloration in Animals. Oxford University Press. p. 10.
  6. ^ "RTO-TM-SCI-096 - Multispectral Camouflage for the Soldier System". NATO Research and Technology Organisation.
  7. ^ "Signature Management". Saab Solutions. Retrieved 4 December 2019.
  8. ^ "ANTI-THERMAL SUITS AND CLOAK". Intermat.
  9. ^ "Anti Thermal IR Coating". Motley-Exim. Retrieved 30 April 2013.
  10. ^ "Multispectral Camouflage for the Soldier System (SCI-096)" (PDF). NATO RTO Task Group.
  11. ^ "Camouflage net". BLÜCHER SYSTEMS®. Retrieved 30 April 2013.
  12. ^ "Multispectral Camouflage Nets". Raksha Supreme Camouflage. Retrieved 30 April 2013.
  13. ^ "MCS Mobile Camouflage System: Protection on the Move". SAAB Group. 2013. Retrieved 31 December 2020.
  14. ^ Innovative Multispectral Camouflage Solutions
  15. ^ "Special Operations Tactical Suit (SOTCAS)". defense-update.com. Defense-Update. 27 January 2005.
  16. ^ "Royal Danish Army Orders Saab Barracuda Camouflage". overtdefense.com. Overt Defense. 15 January 2019.
  17. ^ "More than meets the eye: Army selects next-gen camouflage system". www.armytimes.com. Army Times. 7 November 2018.
  18. ^ Shukla, Ajai (27 November 2024). "IIT Kanpur develops revolutionary tech to make aircraft invisible to radar". Business Standard. Retrieved 28 November 2024.
  19. ^ "IIT Kanpur Unveils Groundbreaking Revolutionary Camouflage Technology for Defence". Financialexpress. 2024-11-28. Retrieved 2024-11-28.
  20. ^ Nave, C.R. "The Electromagnetic Spectrum". HyperPhysics. Hosted by Georgia State University Department of Physics and Astronomy. Retrieved 30 April 2013.
  21. ^ "DSEi 2023: Saab Barracuda reveals new camouflage system". shephardmedia.com. 2023-09-05. Retrieved 2023-09-05.