The newest Russian radar "Sunflower", seeing beyond the horizon

The notification of a possible attack and the detection of aircraft, helicopters, missiles, including low-flying ones, is one of the main tasks of the Russian air defense forces. Recently, they received another tool for its implementation.

The new "Sunflower" radar can detect targets previously unavailable for radar stations. They "see" objects that are beyond obstacles, and even those that, according to all the laws of physics, can not be noticeable because they are on the side of the planet hidden by the horizon. The beams emitted by the antennas of modern locators usually propagate in a straight line, they operate only in direct line of sight conditions, but this radar is unique.

Out-of-band notification

The principle of the over-horizon vision was reflected in the design of several Russian radar stations of the latest generation. Among them, the system "Container", "Taurus" and "Wave". They work on the diffraction principle, which means the ability of the signals emitted by them to envelop obstacles both in the forward and backward directions. Russian experts are world leaders in the field of high-frequency location, such developments are currently considered the most revolutionary and have no analogues. The "Sunflower - E" radar is a modification intended for export deliveries to countries considered strategic allies of the Russian Federation. It has a target detection radius of up to 300 km. The system is clearly defensive in nature and is not designed to conduct aggressive wars.

What is diffraction?

Everyone knows the effect of light refraction. Even if the direct rays of the sun or other light source do not enter the interior, it can be quite light. If the waves could only spread in a straight line, then in many places there would be complete darkness. It is through refraction and reflection that objects become visible. The phenomenon is not just about light: for example, signals from shortwave radio stations are easily received on the opposite side of the planet. They go around the Earth, reflected from the ionosphere, and safely reach the antennas of the receivers.

This is how the radar station "Volna" works, the design of which takes into account the reflectivity of the surface and ionosphere. The radar "Sunflower" is arranged, at first glance, is simpler: it does not use the physical properties of the upper layers of the atmosphere. But its over-horizon possibilities from this do not become smaller. The specialists of the research institute for long-distance radio communications do not disclose technical details, but it is known that the system creates an all-altitude radar field by short-wave signals, which, as is known from the course of wave physics, can penetrate into any points of three-dimensional space.

From "Arc" to "Sunflower"

Experiments on the over-horizon location were carried out in the USSR back in the 1960s. Systems developed then and later, were conceived very boldly, but were costly. Constructed huge radiating structures ("Doug" in the districts of the cities of Nikolaev, Chernobyl and Komsomolsk-on-Amur), and their purpose was the overseas continent, from where the launches of ICBMs were expected. Theoretically, they could estimate the situation within a radius of 10 thousand km, but in practice the information obtained with their help could not be completely trusted. These stations the Americans nicknamed "Russian woodpeckers" for the specific nature of the interference created by them on the air. The unevenness of the ionosphere had a bad effect on the effectiveness of the system, besides, potential adversaries learned to introduce additional distortions, for which in Alaska, Japan and Norway high-power radiators were built. Nevertheless, the work continued, there was an experience that found application much later, with the creation of modern over-the-horizon detection facilities, including the Sunflower radar.

What is known to the public

The system was first presented at the international exhibition IMDS-2007, which was held in St. Petersburg and devoted to naval armaments. A year later the demonstration of the radar "Sunflower" was held at the salon "Euronual-2008", where special emphasis was placed on the export version with the index "E". The Brazilian delegation showed great interest in the new system, but its main purpose was still to ensure the security of the Russian coastal borders. April 2014 was the date when for the first time large-scale practical tests of the "Sunflower" radar were conducted in conditions as close as possible to combat radars. They passed in the Caspian, and the ships of the flotilla served as training purposes, as did the missiles launched by them. In order to complicate the task, the latest URIC "Uglich" and "Grad Sviyazhsk", built using the "Stells" technology, took part in the maneuvers.

What is Sunflower?

This system is not mobile or small. The antennas (receiving and emitting) fields take up a lot of space and can be separated far enough from each other. The work of the station goes in the decimeter range, it is able to detect, accompany, identify and give out target designations of the country's air defenses in automatic mode over hundreds of aircraft and three hundred ships (above-water) in any weather. The range is up to 450 kilometers with a 120 ° viewing sector. The consumed electric power is 200 kW. For safety, all electronic equipment is mounted in special protected containers. With its help (in addition to direct tasks), the meteorological situation, radio interference and physical conditions of the sea surface can be analyzed in passing.

This is almost all information about the export version of the system. Perhaps the exercises with the Russian radar "Sunflower", intended for "internal use", revealed great possibilities for installation.

There are also problems. Thus, the "one-to-one" recognition equipment, operating only on line of sight, so far is difficult to reconcile with this short-wave radar station.

From the Arctic to the Crimea

The "Sunflower" radar, according to S. Boev, General Director of RTI, is in a state of permanent improvement. So, special climatic conditions of the Arctic require special approaches to some constructive solutions. Precision and quality characteristics of the station are also continuously increasing. The security of the Far Eastern coast requires at least five such systems. One should work in the direction of the Bosphorus (Crimea). In the North, they are also needed. And then - according to the reasons of the General Staff.