Editing Kolchuga passive sensor (section)

{{Short description|Soviet radar detector}}
{{More citations needed|date=October 2009}}
[[Image:Kolchuga-passive-radar MAKS2009.jpg|thumb|right|280px|Kolchuga passive sensor]]
The '''Kolchuga''' (Кольчуга ''Chainmail'') passive sensor is an [[electronic-warfare support measures]] (ESM) system developed in the [[Soviet Union]] and manufactured in [[Ukraine]]. Its detection range is limited by line-of-sight but may be up to {{convert|800|km|mi|abbr=on}} for very high altitude, very powerful emitters. Frequently referred to as ''Kolchuga Radar'', the system is not really a [[radar]], but an ESM system comprising three or four [[receiver (radio)|receivers]], deployed tens of kilometres apart, which detect and track aircraft by [[triangulation]] and [[multilateration]] of their [[radiofrequency|RF]] emissions.