The vehicle-mounted passive electronic long range monitoring radar system KOLCHUGA

The vehicle-mounted passive electronic long range monitoring radar system KOLCHUGA provides identification, early warning and location of all known radio frequency emitters mounted on land, sea or air platforms, and it is capable of overriding ‘stealth’ technologies. Unlike normal radars which send out waves that bounce back from the target, KOLCHUGA is a passive system. KOLCHUGA’s operation is based on the ‘passive radiolocation’ principle, which means to say that the radar can spot hostile emissions from land, sea or aerial platforms while remaining ‘invisible’ to enemy detection assets due to the absence of own radiation. No modern military aircraft, tank, ship or surface-to-air missile system can exist without its own radar. Without a radiating aerial it is simply “blind”. That is why every aircraft, ship, and ground-based radar complex has active radiolocation devices. These devices are always on, emitting radio signals. Each specific type of hardware emits signals within different parameters. Consequently, a machine on which an emitting radar is mounted can be identified, a task which is successfully performed with the KOLCHUGA radar. Besides, at attacking object detected by a passive radar is never aware of its detection and so has no reason to activate its own defenses.

Three KOLCHUGA stations would normally operate along with a command vehicle to provide accurate triangulation on a target while designating it to an air defense system. A complex consisting of three KOLCHUGA radar stations makes it possible to spot ground and surface targets and trace their movements within a radius of 600 kilometers (air targets at the 10 km altitude – up to 800 km) along a front of 1,000 km, which makes an effective early warning air defense system. The KOLCHUGA station is equipped with five meter-, decimeter- and centimeter-range aerials, which provide for high radio sensitivity within a 110 dB/W – 155 dB/W swath, depending on the frequency. A parallel 36-channel preset receiver makes it possible to spot instantly, identify, and classify signals from any source with unlimited input density within the entire frequency range from 130MHz to 18,000MHz.

All radio objects are spotted and identified automatically, a powerful computer digitizing and identifying targets by comparing their parameters with the available databank, results being shown on a field display. Special inhibitory sorters omit up to 24 interfering signals, and tracking sorters make it possible to synchronously sort out and track signals from 32 targets. All normal operations require only one operator (two other operators work on a shift basis for 24-hour duty), who controls the station through dialog with a PC. KOLCHUGA stations are accommodated on KrAZ-type cross-country truck chassis. They are powered by an electrical generator set and equipped with air conditioning and ventilation systems. The KOLCHUGA withstands ambient temperatures ranging from -50oC to +50oC.

The KOLCHUGA mobile passive electronic long-range monitoring radar system has been accepted as standard issue for the Ukrainian Armed Forces.

Operating frequency ranges in seven portions of the bandwidth, MHz



Radio sensitivity (depending on the operating frequency range), dB/W


Aerial’s sector in azimuth (when operated manually or autonomously), degrees


Rotating frequency, rounds per minute 






Scan sector in azimuth (for any pre-determined sector of interest), degrees


All-round view spectrum, GHz


Analysis spectrum, GHz


Detailed surveillance spectrum, MHz


Interval between outages, hours