“Even the latest aircraft will not hide”: how Russia is improving radar intelligence. Radar stations: history and basic principles of operation Promising radars
Over the past years, the main way to ensure low visibility of aircraft for enemy radar stations has been a special configuration of external contours. Stealth aircraft are designed in such a way that the radio signal sent by the station is reflected anywhere, but not in the direction of the source. In this way, the power of the reflected signal received by the radar is significantly reduced, which makes it difficult to detect an aircraft or other object made using this technology. Special radar absorbing coatings are also somewhat popular, but in most cases they only help from radar stations operating in a certain frequency range. Since the effectiveness of radiation absorption primarily depends on the ratio of coating thickness and wavelength, most of these paints protect the aircraft only from millimeter waves. More thick layer paints, being effective against waves with a longer length, simply will not allow an airplane or helicopter to take off.
The development of technologies for reducing radio visibility has led to the emergence of means of countering them. For example, first theory, and then practice, showed that stealth aircraft can be detected, including with the help of fairly old radar stations. Thus, the Lockheed Martin F-117A aircraft shot down in 1999 over Yugoslavia was detected using the standard radar of the S-125 anti-aircraft missile system. Thus, even for decimeter waves, a special coating does not become a difficult obstacle. Of course, an increase in the wavelength affects the accuracy of determining the coordinates of the target, however, in some cases, such a price for detecting an inconspicuous aircraft can be considered acceptable. However, radio waves, regardless of their length, are subject to reflection and scattering, which leaves the issue of specific forms of stealth aircraft relevant. However, this problem can also be solved. In September of this year, a new tool was presented, the authors of which promised to solve the issue of scattering of radar waves.
At the Berlin ILA-2012 exhibition held in the first half of September, the European aerospace concern EADS presented its new development, which, according to the authors, can turn all ideas about the stealth of aircraft and the means of combating them. The Cassidian company, which is part of the concern, proposed its own version of the passive radar option. The essence of such a radar station lies in the absence of any radiation. In fact, a passive radar is a receiving antenna with appropriate equipment and calculation algorithms. The whole complex can be installed on any suitable chassis. For example, in the advertising materials of the EADS concern, a two-axle minibus appears, in the cabin of which all the necessary electronics are mounted, and on the roof there is a telescopic rod with a block of receiving antennas.
The principle of operation of a passive radar, at first glance, is very simple. Unlike conventional radars, it does not emit any signals, but only receives radio waves from other sources. The equipment of the complex is designed to receive and process radio signals emitted by other sources, such as traditional radars, television and radio stations, as well as communications using a radio channel. It is assumed that a third-party source of radio waves is located at some distance from the passive radar receiver, due to which its signal, hitting a stealth aircraft, can be reflected towards the latter. Thus, the main task of a passive radar is to collect all radio signals and process them correctly in order to isolate that part of them that was reflected from the desired aircraft.
In fact, this idea is not new. The first proposals to use passive radar appeared quite a long time ago. However, until recently, such a method of detecting targets was simply impossible: there was no equipment that would allow to single out from all the received signals exactly the one that was reflected by the target object. Only in the late nineties, the first full-fledged developments began to appear that could provide the extraction and processing of the necessary signal, for example, the American Silent Sentry project from Lockheed Martin. The employees of the EADS concern, also, as they say, managed to create the necessary set of electronic equipment and the corresponding software, which can "identify" the reflected signal by some signs and calculate parameters such as elevation angle and range to the target. More accurate and detailed information, of course, was not reported. But representatives of EADS spoke about the possibility of a passive radar to monitor the entire space around the antenna. In this case, the information on the operator's display is updated every half a second. It was also reported that the passive radar so far operates only in three radio bands: VHF, DAB (digital radio) and DVB-T (digital television). The error in target detection, according to official data, does not exceed ten meters.
From the design of the passive radar antenna unit, it can be seen that the complex can determine the direction to the target and the elevation angle. However, the question of determining the distance to the detected object remains open. Since there is no official data on this subject, we will have to make do with the available information about passive radars. EADS representatives claim their radar works with signals used by both radio and television broadcasts. It is quite obvious that their sources have a fixed location, which is also known in advance. A passive radar can simultaneously receive a direct signal from a television or radio station, as well as search for it in a reflected and attenuated form. Knowing its own coordinates and the coordinates of the transmitter, the passive radar electronics can calculate the approximate range to the target by comparing the direct and reflected signals, their power, azimuths and elevation angles. Judging by the declared accuracy, European engineers managed to create not only viable, but also promising equipment.
It is also worth noting that the new passive radar clearly confirms the fundamental possibility practical use Radar of this class. It is possible that other countries will be interested in the new European development and will also start their work in this direction or speed up the existing ones. So, the United States can resume serious work on the Silent Sentry project. In addition, the French company Thale and the English Roke Manor Research had certain developments on this topic. Much attention to the subject of passive radars can eventually lead to their wide distribution. In this case, already now you need to roughly imagine what the consequences for the appearance modern war will have such a technique. The most obvious consequence is to minimize the advantages of stealth aircraft. Passive radars will be able to determine their location, ignoring both stealth technologies. Also, a passive radar can make anti-radar missiles useless. New radars are capable of using the signal of any radio transmitter of the appropriate range and power. Accordingly, the enemy aircraft will not be able to detect the radar by its radiation and attack with anti-radar ammunition. The destruction of all large emitters of radio waves, in turn, turns out to be too complicated and expensive. In the end, a passive radar can theoretically work with transmitters of the simplest design, which, in terms of cost, will cost much less than countermeasures. The second problem for countering passive radars concerns electronic warfare. To effectively suppress such a radar, it is necessary to “jam” a sufficiently large frequency range. At the same time, the proper effectiveness of electronic warfare means is not ensured: if there is a signal that does not fall into the suppressed range, a passive radar station can switch to using it.
Undoubtedly, the widespread use of passive radar stations will lead to the emergence of methods and means of counteracting them. However, at present, the development of Cassidian and EADS has almost no competitors and analogues, which so far allows it to remain sufficiently promising. Representatives of the concern-developer claim that by 2015 the experimental complex will become a full-fledged means of detecting and tracking targets. For the time remaining before this event, designers and the military of other countries should, if not develop their own analogues, then at least form their own opinion on the topic and come up with at least general methods of counteraction. First of all, the new passive radar can hit the combat potential of the US Air Force. It is the United States that pays the most attention to the stealth of aircraft and creates new designs with the maximum possible use of stealth technology. If passive radars confirm their ability to detect aircraft that are hardly visible to traditional radars, then the appearance of promising American aircraft may undergo serious changes. As for other countries, they do not yet put stealth at the forefront, and this, to a certain extent, will reduce possible unpleasant consequences.
According to the websites:
http://spiegel.de/
http://heads.com/
http://cassidian.com/
http://defencetalk.com/
http://wired.co.uk/
According to the Ministry of Defense of the Russian Federation, in 2017, 70 (radar) were delivered to the Aerospace Forces (VKS) of Russia. Radars are necessary for conducting radar reconnaissance, the tasks of which include the timely detection of various dynamic targets.
“In 2017, more than 70 newest radar stations were received by the units of the radio engineering troops of the Aerospace Forces. Among them are medium and high altitude radar systems Nebo-M, medium and high altitude radars Opponent, All-Altitude Detector, Sopka-2, low-altitude radars Podlyot-K1 and Podlyot-M, " Casta-2-2", "Gamma-C1", as well as modern complexes of automation equipment "Foundation" and other means," the Ministry of Defense said in a statement.
As noted in the department, the main feature of the latest domestic radars is that they are created on a modern element base. All processes and operations performed by these machines are automated as much as possible.
At the same time, control systems and Maintenance radar stations have become more simple.
Defense element
Radar stations in the Russian Aerospace Forces are designed to detect and track air targets, as well as for target designation by anti-aircraft missile systems(ZRK). Radars are one of key elements air, anti-missile and space defense of Russia.
The Nebo-M radar system is capable of detecting targets at ranges from 10 to 600 km (all-round view) and from 10 to 1800 km (sector view). The station can track both large and small objects made using stealth technology. The deployment time of "Sky-M" is 15 minutes.
To determine the coordinates and escort of strategic and tactical aircraft and detect American missiles"air-to-surface" type ASALM The Russian Aerospace Forces use the Opponent-GE radar station. The characteristics of the complex allow it to track at least 150 targets at an altitude of 100 m to 12 km.
Mobile radar complex 96L6-1 / 96L6E "All-altitude detector" is used in armed forces RF for issuing target designation to air defense systems. The unique machine can detect a wide range of aerodynamic targets (aircraft, helicopters and drones) at altitudes up to 100 km.
Radars "Podlyot-K1" and "Podlyot-M", "Casta-2-2", "Gamma-S1" are used to monitor the air situation at altitudes from a few meters to 40-300 km. The complexes recognize all types of aviation and rocket technology and can be operated at temperatures from -50 to +50 °C.
- Mobile radar complex for detecting aerodynamic and ballistic objects at medium and high altitudes "Nebo-M"
The main task of the Sopka-2 radar complex is to obtain and analyze information about the air situation. The Ministry of Defense uses this radar most actively in the Arctic. The high resolution of "Sopka-2" allows you to recognize individual air targets that fly as part of a group. Sopka-2 is capable of detecting up to 300 objects within 150 km.
Almost all of the above radar systems ensure the security of Moscow and the Central Industrial Region. By 2020, the share of modern weapons in the air defense units of the Moscow zone of responsibility should reach 80%.
At the stage of re-equipment
All modern radars consist of six main components: a transmitter (electromagnetic signal source), an antenna system (transmitter signal focusing), a radio receiver (received signal processing), output devices (indicators and a computer), noise protection equipment and power supplies.
Domestic radars can detect aircraft, drones and missiles, tracking their movement in real time. Radars provide timely receipt of information about the situation in the airspace near the borders of the Russian Federation and hundreds of kilometers from state borders. In military parlance, this is called radar reconnaissance.
The incentive for improving the radar intelligence of the Russian Federation is the efforts of foreign states (primarily the United States) to create low-observable aircraft, cruise and ballistic missiles. So, over the past 40 years, the United States has been actively developing stealth technologies, which are designed to ensure that the radar approach to enemy lines is invisible to the radar.
The huge military budget (over $600 billion) enables American designers to experiment with radar-absorbing materials and the geometric shapes of aircraft. In parallel with this, the United States is improving radar protection equipment (ensuring noise immunity) and radar jamming devices (interfering with radar receivers).
Military expert Yuri Knutov is convinced that Russian radar reconnaissance is capable of detecting almost all types of air targets, including American F-22 and F-35 fifth-generation fighters, stealth aircraft (in particular, strategic bomber B-2 Spirit) and objects flying at extremely low altitudes.
- Radar screen that shows a target image synchronized with the movement of the antenna
- Ministry of Defence Russian Federation
“Even the newest american planes. The Ministry of Defense attaches great importance to the development of the radar, because these are the eyes and ears of the Aerospace Forces. The advantages of the latest stations now entering service are long range, high noise immunity and mobility, ”Knutov said in an interview with RT.
The expert noted that the United States does not stop working on the development of radar suppression systems, realizing its vulnerable position in front of Russian radars. In addition, the American army is armed with special anti-radar missiles, which are guided by the radiation of stations.
“The latest Russian radars feature an incredible level of automation compared to the previous generation. Astonishing progress has been made in improving mobility. IN Soviet years it took almost a day to deploy and collapse the station. Now this is done within half an hour, and sometimes within a few minutes, ”said Knutov.
The interlocutor of RT believes that the radar systems of the VKS are adapted to counteract a high-tech enemy, reducing the likelihood of his penetration into the airspace of the Russian Federation. According to Knutov, today the radio engineering troops of Russia are at the stage of active re-equipment, but by 2020 most units will be equipped with modern radar stations.
Good evening everyone :) I rummaged around the Internet after visiting a military unit with a considerable number of radars.
The radars themselves were very interested. I think that not only me, so I decided to post this article :)
Radar stations P-15 and P-19
Radar P-15 decimeter range is designed to detect low-flying targets. Adopted in 1955. It is used as part of radar posts of radio engineering formations, control batteries of anti-aircraft artillery and missile formations of the operational level of air defense and at control points of air defense of the tactical level.
The P-15 station is mounted on one vehicle together with an antenna system and is deployed to a combat position in 10 minutes. The power unit is transported in a trailer.
The station has three modes of operation:
- amplitude;
- amplitude with accumulation;
- coherent-pulse. 
The P-19 radar is intended for conducting reconnaissance of air targets at low and medium altitudes, detecting targets, determining their current coordinates in azimuth and identification range, as well as for transmitting radar information to command posts and to interfaced systems. It is a mobile two-coordinate radar station placed on two vehicles.
The first vehicle accommodates receiving and transmitting equipment, anti-interference equipment, indicator equipment, equipment for transmitting radar information, simulating, communicating and interfacing with consumers of radar information, functional control and equipment for a ground-based radar interrogator.
The second car houses the radar antenna-rotary device and power supply units.
Difficult climatic conditions and the duration of operation of the P-15 and P-19 radar stations have led to the fact that by now most of the radars require restoration of the resource.
The only way out of this situation is the modernization of the old radar fleet based on the Kasta-2E1 radar.
The modernization proposals took into account the following:
Keeping intact the main radar systems (antenna system, antenna rotation drive, microwave path, power supply system, vehicles);
Possibility of carrying out modernization in operating conditions with minimal financial costs;
The possibility of using the released P-19 radar equipment for the restoration of products that have not been upgraded.
As a result of the modernization, the P-19 mobile solid-state low-altitude radar will be able to perform the tasks of monitoring airspace, determining the range and azimuth of air objects - airplanes, helicopters, remotely piloted aircraft and cruise missiles, including those operating at low and extremely low altitudes, at background of intense reflections from the underlying surface, local objects and hydrometeorological formations.
The radar can be easily adapted for use in various systems military and civil purpose. Can be applied to information support air defense systems, air force, coastal defense systems, rapid reaction forces, civil aviation aircraft traffic control systems. In addition to the traditional use as a means of detecting low-flying targets in the interests of the armed forces, the modernized radar can be used to control airspace in order to prevent the transportation of weapons and drugs by low-altitude, low-speed and small-sized aircraft in the interests of special services and police units involved in the fight against drug trafficking and arms smuggling .
Modernized radar station P-18
Designed to detect aircraft, determine their current coordinates and issue target designation. It is one of the most popular and cheapest meter stations. The resource of these stations has been largely exhausted, and their replacement and repair are difficult due to the lack of an element base that is outdated by now.
To extend the service life of the P-18 radar and improve a number of tactical and technical characteristics, the station was modernized on the basis of an assembly kit with a service life of at least 20-25 thousand hours and a service life of 12 years.
Four additional antennas have been introduced into the antenna system for adaptive suppression of active interference, mounted on two separate masts.
- replacement of the obsolete element base of the P-18 radar equipment with a modern one;
- replacement of a tube transmitter with a solid-state one;
- introduction of a signal processing system on digital processors;
- introduction of a system of adaptive suppression of active noise interference;
- introduction of systems for secondary processing, control and diagnostics of equipment, display of information and control on the basis of a universal computer;
- ensuring interfacing with modern automated control systems.
As a result of modernization:
- reduced volume of equipment;
- increased reliability of the product;
- increased noise immunity;
- improved accuracy characteristics;
- improved performance.
The mounting kit is built into the radar equipment cabin instead of the old equipment. The small dimensions of the mounting kit allow for the modernization of products on site.
Radar complex P-40A
Rangefinder 1RL128 "Armor"
The radar range finder 1RL128 "Bronya" is a radar of all-round visibility and, together with the radar altimeter 1RL132, forms a three-coordinate radar complex P-40A.
Rangefinder 1RL128 is designed for:
- detection of air targets;
- determination of the slant range and azimuth of air targets;
- automatic output of the altimeter antenna to the target and display of the target height value according to the altimeter data;
- determination of state ownership of goals ("friend or foe");
- control of their aircraft using the all-round visibility indicator and the R-862 aircraft radio station;
- direction finding of active jammers directors.
The radar complex is part of radio engineering formations and air defense formations, as well as anti-aircraft missile (artillery) units and military air defense formations.
Structurally, the antenna-feeder system, all equipment and the ground-based radar interrogator are placed on a 426U self-propelled tracked chassis with its own components. In addition, it houses two gas turbine power units.
Two-coordinate standby radar "Nebo-SV"
Designed for detection and identification of air targets in standby mode when operating as part of military air defense radar units, equipped and not equipped with automation.
The radar is a mobile coherent-pulse radar located on four transport units (three cars and a trailer).
The first vehicle accommodates receiving and transmitting equipment, anti-interference equipment, indicator equipment, equipment for auto-detection and transmission of radar information, simulation, communication and documentation, interfacing with consumers of radar information, functional monitoring and continuous diagnostics, equipment for ground-based radar interrogator (NRZ).
The second car houses the radar antenna-rotary device.
The third car has a diesel power plant.
An NRZ antenna-rotary device is placed on the trailer.
The radar can be equipped with two external all-round visibility indicators and interface cables.
Mobile three-coordinate radar station 9S18M1 "Kupol"
Designed to provide radar information to command posts of anti-aircraft missile formations and military air defense units and command posts of air defense system facilities of motorized rifle and tank divisions equipped with Buk-M1-2 and Tor-M1 air defense systems.
The 9S18M1 radar is a three-coordinate coherent-pulse detection and target designation station that uses long-duration probing pulses, which provides high-energy emitted signals.
The radar is equipped with digital equipment for automatic and semi-automatic coordinate pickup and equipment for identifying detected targets. The entire process of radar functioning is maximally automated due to the use of high-speed computing electronic means. To improve the efficiency of work in conditions of active and passive interference, the radar uses modern methods and means of interference protection.
The 9S18M1 radar is mounted on a cross-country tracked chassis and is equipped with an autonomous power supply system, navigation, orientation and geolocation equipment, telecode and voice radio communications. In addition, the radar has a built-in automated functional control system that provides a quick search for a faulty replaceable element and a simulator for processing the skills of operators. To transfer them from traveling to combat and back, devices for automatic deployment and collapse of the station are used.
The radar can operate in harsh climatic conditions, move under its own power on roads and off-road, and be transported by any mode of transport, including air.
air defense air force
Radar station "Defence-14"
Designed for long-range detection and measurement of the range and azimuth of air targets when operating as part of an automated control system or autonomously.
The radar is placed on six transport units (two semi-trailers with equipment, two with an antenna-mast device and two trailers with a power supply system). A separate semi-trailer has a remote post with two indicators. It can be removed from the station at a distance of up to 1 km. To identify air targets, the radar is equipped with a ground-based radio interrogator.
The station uses a folding design of the antenna system, which made it possible to significantly reduce the time of its deployment. Protection against active noise interference is provided by the frequency tuning and a three-channel auto-compensation system, which allows you to automatically form "zeros" in the antenna pattern in the direction of the jammers. To protect against passive interference, coherent-compensating equipment based on potentialoscopic tubes was used.
The station provides three modes of viewing space:
- "lower beam" - with an increased target detection range at low and medium altitudes;
- "upper beam" - with an increased upper boundary of the detection zone in elevation;
Scanning - with alternate (through the review) inclusion of the upper and lower beams.
The station can be operated at temperatures environment± 50 °С, wind speed up to 30 m/s. Many of these stations were exported and are still operated by the troops.
Radar "Oborona-14" can be upgraded on a modern element base using solid-state transmitters and digital system information processing. The developed mounting kit of the equipment allows, right at the position of the consumer, to perform work on upgrading the radar in a short time, bring its characteristics closer to the characteristics of modern radars, and extend the service life by 12 - 15 years at a cost several times less than when purchasing a new station.
Radar station "Sky"
Designed for detection, identification, measurement of three coordinates and tracking of air targets, including aircraft manufactured using stealth technology. It is used in the air defense forces as part of an automated control system or autonomously.
The all-round radar "Sky" is located on eight transport units (on three semi-trailers - an antenna-mast device, on two - equipment, on three trailers - an autonomous power supply system). There is a remote device transported in container boxes.
The radar operates in the meter wavelength range and combines the functions of a range finder and an altimeter. In this range of radio waves, the radar is not vulnerable to homing projectiles and anti-radar missiles operating in other ranges, and these weapons are currently absent in the operating range. In the vertical plane, electronic scanning with an altimeter beam is implemented (without the use of phase shifters) in each range resolution element.
Noise immunity under the influence of active interference is provided by adaptive tuning of the operating frequency and a multi-channel auto-compensation system. The passive interference protection system is also built on the basis of correlation autocompensators.
For the first time, to ensure noise immunity under the influence of combined interference, space-time decoupling of protection systems from active and passive interference has been implemented.
Measurement and issuance of coordinates are carried out using automatic pickup equipment based on a built-in special calculator. Available automated system control and diagnosis.
The transmitting device is characterized by high reliability, which is achieved through 100% redundancy of a powerful amplifier and the use of a group solid-state modulator.
Radar "Nebo" can be operated at ambient temperature ± 50 °С, wind speed up to 35 m/s.
Three-coordinate mobile surveillance radar 1L117M
Designed to monitor airspace and determine three coordinates (azimuth, slant range, altitude) of air targets. The radar station is built on modern components, has a high potential and low energy consumption. In addition, the radar has a built-in state identification interrogator and equipment for primary and secondary data processing, a set of remote indicator equipment, due to which it can be used in automated and non-automated air defense systems and the Air Force for flight control and interception guidance, as well as for air control traffic (ATC).
Radar 1L117M is an improved modification of the previous model 1L117.
The main difference of the improved radar is the use of a klystron transmitter output power amplifier, which made it possible to increase the stability of the emitted signals and, accordingly, the coefficient of suppression of passive interference and improve the characteristics of low-flying targets.
In addition, due to the presence of frequency agility, the performance of the radar in the presence of interference has been improved. New types of signal processors were used in the radar data processing device, and the remote control, monitoring and diagnostics system was improved.
The main set of radar 1L117M includes:
Machine No. 1 (receiving-transmitting) consists of: lower and upper antenna systems, a four-channel waveguide tract with receiving-transmitting equipment for PRL and state identification equipment;
Machine No. 2 has a pick-up cabinet (point) and an information processing cabinet, a radar indicator with remote control;
Machine number 3 carries two diesel power plants (main and backup) and a set of radar cables;
Machines No. 4 and No. 5 contain auxiliary equipment(spare parts, cables, connectors, mounting kit, etc.). They are also used for transporting a disassembled antenna system.
The view of space is provided by the mechanical rotation of the antenna system, which forms a V-shaped radiation pattern, consisting of two beams, one of which is located in the vertical plane, and the other - in the plane located at an angle of 45 to the vertical. Each radiation pattern, in turn, is formed by two beams formed at different carrier frequencies and having orthogonal polarization. The radar transmitter generates two successive phase code-shift keyed pulses at different frequencies, which are sent to the feeds of the vertical and inclined antennas through the waveguide path.
The radar can operate in a rare pulse repetition rate mode, providing a range of 350 km, and in a frequent burst mode with a maximum range of 150 km. At higher speeds (12 rpm), only fast mode is used.
The receiving system and digital equipment of the SDC ensure the reception and processing of target echo signals against the background of natural interference and meteorological formations. The radar processes echoes in a "moving window" with a fixed level of false alarms and has intersurvey processing to improve target detection in the background of interference.
The SDC equipment has four independent channels (one for each receiving channel), each of which consists of coherent and amplitude parts.
The output signals of the four channels are combined in pairs, as a result of which normalized amplitude and coherent signals of the vertical and oblique beams are fed to the radar extractor.
The data acquisition and processing cabinet receives data from the PLR and state identification equipment, as well as rotation and synchronization signals, and provides: selection of the amplitude or coherent channel in accordance with the information of the interference map; secondary processing of radar data with the construction of trajectories according to radar data, the combination of radar marks and state identification equipment, displaying the air situation on the screen with forms "attached" to targets; target location extrapolation and collision prediction; introduction and display graphic information; identification mode control; solving problems of guidance (interception); analysis and display of meteorological data; statistical evaluation of radar operation; development and transmission of exchange messages to control points.
The remote monitoring and control system provides automatic operation of the radar, control of operating modes, performs automatic functional and diagnostic control technical condition equipment, identification and troubleshooting with a display of the methodology for carrying out repair and maintenance work.
The remote control system provides localization of up to 80% of faults with an accuracy of a typical replacement element (TEZ), in other cases - up to a group of TEZs. The workplace display screen provides a complete display of the characteristic indicators of the technical condition of the radar equipment in the form of graphs, diagrams, functional diagrams and explanatory inscriptions.
It is possible to transmit radar data via cable communication lines to remote indicator equipment for air traffic control and providing guidance and interception control systems. The radar is provided with electricity from an autonomous power source included in the delivery package; can also be connected to an industrial network 220/380 V, 50 Hz.
Radar station "Casta-2E1"
Designed to control airspace, determine the range and azimuth of air objects - airplanes, helicopters, remotely piloted aircraft and cruise missiles flying at low and extremely low altitudes against the background of intense reflections from the underlying surface, local objects and hydrometeorological formations.
Mobile solid-state radar "Casta-2E1" can be used in various military and civil systems - air defense, coastal defense and border control, air traffic control and airspace control in airfield areas.
Distinctive features of the station:
- block-modular construction;
- interfacing with various consumers of information and data output in analog mode;
- automatic system control and diagnostics;
- additional antenna-mast kit for mounting the antenna on a mast with a lifting height of up to 50 m
- solid-state construction of the radar
- high quality of the output information under the influence of impulse and noise active interference;
- the possibility of protection and interfacing with means of protection against anti-radar missiles;
- the ability to determine the nationality of the detected targets.
The radar includes a hardware machine, an antenna machine, an electrical unit on a trailer and a remote workplace operator, allowing you to control the radar from a protected position at a distance of 300 m.
The radar antenna is a system consisting of two reflector antennas with feeds and compensation antennas arranged in two floors. Each antenna mirror is made of metal mesh, has an oval contour (5.5 m x 2.0 m) and consists of five sections. This makes it possible to stack the mirrors during transportation. When using a standard support, the position of the phase center of the antenna system at a height of 7.0 m is ensured. The survey in the elevation plane is carried out by forming one beam special form, in azimuth - due to uniform circular rotation at a speed of 6 or 12 rpm.
To generate probing signals in the radar, a solid-state transmitter is used, made on microwave transistors, which makes it possible to obtain a signal with a power of about 1 kW at its output.
Receivers perform analog processing of signals from three main and auxiliary receiving channels. To amplify the received signals, a solid-state low-noise microwave amplifier with a transmission coefficient of at least 25 dB and an intrinsic noise level of not more than 2 dB is used.
The radar modes are controlled from the operator's workstation (OWO). Radar information is displayed on a coordinate-sign indicator with a screen diameter of 35 cm, and the results of monitoring the parameters of the radar - on a table-sign display.
The Kasta-2E1 radar remains operational in the temperature range from -50 °С to +50 °С in conditions of precipitation (hoarfrost, dew, fog, rain, snow, ice), wind loads up to 25 m/s and the location of the radar on altitude up to 2000 m above sea level. The radar can operate continuously for 20 days.
To ensure high availability of the radar, there is a redundant equipment. In addition, the radar kit includes spare equipment and accessories (spare parts) designed for a year of operation of the radar.
To ensure the readiness of the radar within the entire service life, a group spare parts kit is separately supplied (1 set for 3 radars).
Average radar resource up to overhaul 1 15 thousand hours; average service life before overhaul - 25 years.
Radar "Casta-2E1" has a high modernization ability in terms of improving individual tactical and technical characteristics (increasing potential, reducing the amount of processing equipment, display equipment, increasing productivity, reducing deployment and folding time, increasing reliability, etc.). It is possible to supply the radar in a container version using a color display.
Radar station "Casta-2E2"
Designed to control airspace, determine the range, azimuth, flight level and route characteristics of air objects - airplanes, helicopters, remotely piloted aircraft and cruise missiles, including those flying at low and extremely low altitudes, against the background of intense reflections from the underlying surface , local objects and hydro-meteorological formations. The Kasta-2E2 low-altitude 3D all-round duty radar is used in air defense, coastal defense and border control systems, air traffic control and airspace control in airfield areas. Easily adaptable for use in various civil applications.
Distinctive features of the station:
- block-modular construction of most systems;
- deployment and retraction of the standard antenna system with the help of automated electromechanical devices;
- fully digital processing of information and the possibility of its transmission over telephone channels and radio channels;
- completely solid construction of the transmission system;
- the possibility of mounting the antenna on a light high-rise support of the "Unzha" type, which ensures the rise of the phase center to a height of up to 50 m;
- the possibility of detecting small objects against the background of intense interfering reflections, as well as hovering helicopters while simultaneously detecting moving objects;
- high security against non-synchronous impulse interference when working in dense groupings of electronic equipment;
- a distributed complex of computing tools that automates the processes of detection, tracking, measuring coordinates and identifying the nationality of air objects;
- the possibility of issuing radar information to the consumer in any form convenient for him - analog, digital-analog, digital coordinate or digital trace;
- the presence of a built-in system of functional diagnostic control, covering up to 96% of the equipment.
The radar includes hardware and antenna machines, the main and backup power plants, mounted on three KamAZ-4310 all-terrain vehicles. It has a remote operator's workplace that provides control of the radar, remote from it at a distance of 300 m.
The design of the station is resistant to the effects of overpressure in the front shock wave, equipped with sanitary and individual ventilation devices. The ventilation system is designed to operate in recirculation mode without the use of intake air.
The radar antenna is a system consisting of a double-curvature mirror, a horn feed assembly, and side-lobe reception suppression antennas. The antenna system generates two beams with horizontal polarization on the main radar channel: sharp and cosecant, covering the given field of view.
The radar uses a solid-state transmitter made on microwave transistors, which makes it possible to obtain a signal with a power of about 1 kW at its output.
The radar modes can be controlled both by the operator's commands and by using the capabilities of a complex of computing facilities.
The radar provides stable operation at an ambient temperature of ±50 °С, relative air humidity up to 98%, wind speed up to 25 m/s. Altitude above sea level - up to 3000 m. performance characteristics at the level of the best foreign and domestic samples.
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As RIA Novosti was informed with reference to the press service of the RTI concern, the Voronezh-DM early warning radar station of the new generation, located in the Krasnoyarsk Territory, for the first time detected a ballistic target from North America. This radar, which has become the fruit of the work of two institutes for long-range radar, is a station of high factory readiness. Its deployment takes from a year to a year and a half, while the construction of stations of previous generations took 5-10 years.
Thanks to the high manufacturability of the deployment of Voronezh, by 2018 Russia will have created a network of early warning stations, which will not only allow full control of all missile-hazardous areas, but also direct missile defense systems at targets.
However, even now the area of competence of these stations is extensive. There are 4 stations on combat duty, three more are operating in the mode trial operation. They control airspace from the coast of Morocco to Svalbard, from southern Europe to the northern coast of Africa, from the west coast of the US to India, and over all of Europe, including the UK.
Thus, the vast majority of the "Egyptian pyramids", which, in terms of size and labor spent on their construction, are early warning radars of the previous generation, will be sent to rest. Warning system missile attack(SPNR) will be based on the Voronezh radar. The SPNR also includes a space segment - a satellite network. It began to unfold last year with the launch of the 14F142 Tundra satellite. Satellites track ICBM launches by the torch of working rocket engines.
The Voronezh radar network began to be deployed in 2011 with the commissioning of a station in Pionerskoye, Kaliningrad Region. So far, 4 stations have done an impressive job. Every year they detect and escort up to 40 launched space and ballistic missiles. They warned about 30 dangerous encounters between space objects and spacecraft of the Russian orbital group. 8 times saved the ISS from space debris.
And in 2013, Voronezh exposed the Americans, who decided to conduct a covert reconnaissance operation against the Syrian army. The new radar showed the Pentagon in the clearest way that from now on, even the most disguised actions in the space controlled by Russian radars are visible at a glance.
On September 2, 2013, a radar located in Armavir, Krasnodar Territory, recorded the launch of two of the latest American supersonic missiles in the waters mediterranean sea. Moreover, it is only one of all the radars of this type existing in the world that was able to detect these missiles. The purpose of these launches was to test the reaction time and location of Syrian air defense systems capable of shooting down ballistic targets. The Pentagon said that this event was aimed solely at testing the combat capability of Israel's air defense systems in order to train the military serving them.
However, Anatoly Antonov, Deputy Minister of Defense of the Russian Federation, having met on September 4 with the military attachés of the United States and Israel, showed them the parameters of these launches recorded by Voronezh. The presented ballistic trajectories accurately indicated the goals and objectives of these launches. At the same time, under certain conditions, if the missiles, according to the scenario, did not self-destruct, they could reach the borders of Russia.
This precedent showed American strategists that the new, fourth, generation of Russian SPNR radars in a number of characteristics, the main ones, surpasses American counterparts, most of which have existed since the Cold War.
The response time of the Voronezh phased array antenna is 40 milliseconds. The best American antennas have 60 milliseconds. Well, the most ancient American SPNR radars are completely equipped with giant rotating parabolic antennas. The time of signal processing and transmission to the control center of all data on the speed and trajectory of the target at Voronezh does not exceed 6 seconds. Americans spend 10 seconds on this procedure. Well, the resolutions of the two radars differ already at times. Voronezh determines the coordinates of a target moving at a distance of several hundred kilometers at hypersonic speed with an error of no more than 11 meters.
American stations are able to determine the coordinates of the target with an accuracy of 120 meters horizontally and 90 meters vertically.
Moreover, the target detection range is comparable to the range of Voronezh only for the only, the latest, AN / FPS-132 radar. It is equal to 5000 kilometers, against 6000 kilometers for the Russian radar. The previous developments of the Americans, which continue to be used, only reach 4,500 kilometers.
Strictly speaking, Voronezh is not one replicated station, but a family of stations. Here are the radars it includes:
- "Voronezh-M" meter range. Development of RTI them. A.L. Mints;
- "Voronezh-DM" decimeter range. Development of NIIDAR;
- "Voronezh-VP" - high-potential radar. Development of RTI them. A.L. Mints. Works in the meter range;
- "Voronezh-SM" centimeter range. It is currently at the design stage.
Stations have different radio characteristics, predetermined by the schemes used, the principles for controlling the emitted signals and the methods for processing the received responses. At the same time, due to the existing ability to change the nature of the signal, stations are able to “adjust” to targets for better identification and tracking. Up to 500 targets are tracked simultaneously.
Radars of the Voronezh family, due to the high degree of unification of the nodes, can be modernized in order to increase their capabilities in terms of range and accuracy of target determination.
The appearance of the Voronezh-SM radar station will make it possible to use the SPNR network not only for detection and tracking, but also for targeting missile weapons. Since centimeter-range radars have a resolution that allows solving such a problem.
The range of stations of the family is in the range from 4500 km to 6000 km. The height of the detected objects is up to 4000 km. That is, Voronezh works with both ballistic and aerodynamic aircraft and satellites.
At the moment, there are 4 stations on combat duty:
- "Voronezh-M" (Lehtusi, Leningrad region) controls the airspace from the coast of Morocco to Svalbard. Upgrading is planned, thanks to which it will be possible to control the east coast of the United States;
- "Voronezh-DM" (Armavir, Krasnodar region) controls the airspace from Southern Europe to the northern coast of Africa;
- "Voronezh-DM" (Pionersky, Kaliningrad region) controls the airspace over all of Europe, including the UK;
- "Voronezh-VP" (Mishlevka, Irkutsk region) controls the airspace from the US west coast to India.
3 stations that are in trial operation will be put on alert this year:
- "Voronezh-DM" (Yeniseisk, Krasnoyarsk Territory);
- "Voronezh-DM" (Barnaul, Altai region);
- "Voronezh-M" (Orsk, Orenburg region).
At the moment, two radar stations are being built - in the Komi Republic and in the Amur Region. The construction of another one - in Murmanskaya - is scheduled for next year.
In addition to the undeniable tactical and technical advantages, the Voronezh radars also have economic advantages in comparison with the "Egyptian pyramids" of the previous generation.
They have significantly lower power consumption. If the radar "Daryal", put into operation in 1984, consumes a power equal to 50 MW, then the meter and decimeter "Voronezh" - 0.7 MW each, and the new high-potential radar - 10 MW. This not only benefits operating costs, but also a less bulky cooling system. If "Daryal" needs 150 cubic meters of water per hour for this purpose, then "Voronezh" does not need water for cooling.
Accordingly, new stations are much cheaper - 1.5 billion rubles against 10-20 billion.
Reducing the size and energy consumption while maintaining high technical and performance characteristics achieved through the miniaturization of equipment, as well as through the use of powerful computing technology that optimizes the operation of the stations and allows you to achieve higher resolution while reducing energy costs.
Captain M. Vinogradov,
candidate of technical sciences
Modern radar equipment installed on aircraft and spacecraft, currently represent one of the most intensively developing segments of radio-electronic technology. The identity of the physical principles underlying the construction of these tools makes it possible to consider them within the framework of one article. The main differences between space and aviation radars lie in the principles of radar signal processing associated with different aperture sizes, the propagation of radar signals in different layers of the atmosphere, the need to take into account the curvature of the earth's surface, etc. Despite such differences, the developers of radars with synthesizing aperture (RSA) make every effort to achieve the maximum similarity of the capabilities of these reconnaissance assets.
At present, airborne radars with aperture synthesis make it possible to solve the tasks of specific reconnaissance (to survey the earth's surface in various modes), select mobile and stationary targets, analyze changes in the ground situation, survey objects hidden in forests, and detect buried and small marine objects.
The main purpose of SAR is a detailed survey of the earth's surface.
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| Rice. Fig. 1. Shooting modes of modern SAR (a - detailed, b - overview, c - scanning) | Rice. 2. Examples of real radar images with resolutions of 0.3 m (top) and 0.1 m (bottom) |
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| Rice. 3. View of images when different levels detailing | |
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| Rice. Fig. 4. Examples of fragments of real areas of the earth's surface obtained at the levels of detail DTED2 (left) and DTED4 (right) | |
Due to the artificial increase in the aperture of the onboard antenna, the basic principle of which is the coherent accumulation of the reflected radar signals over the synthesis interval, it is possible to obtain a high resolution in angle. In modern systems, resolution can reach tens of centimeters when operating in the centimeter wavelength range. Similar values of range resolution are achieved through the use of intra-pulse modulation, for example, linear frequency modulation (chirp). The interval for synthesizing the antenna aperture is directly proportional to the flight altitude of the SAR carrier, which ensures that the survey resolution is independent of altitude.
At present, there are three main modes of surveying the earth's surface: overview, scanning, and detailed (Fig. 1). In the survey mode, the survey of the earth's surface is carried out continuously in the capture band, while separating the lateral and anterolateral modes (depending on the orientation of the main lobe of the antenna pattern). The accumulation of the signal is carried out for a time equal to the calculated interval for synthesizing the antenna aperture for the given flight conditions of the radar carrier. The scanning shooting mode differs from the survey one in that the shooting is carried out over the entire width of the swath, in strips equal to the width of the capture swath. This mode is used exclusively in space-based radars. When shooting in the detailed mode, the signal accumulation is carried out at an interval increased compared to the overview mode. The increase in the interval is carried out due to the movement of the main lobe of the antenna pattern, synchronous with the movement of the radar carrier, so that the irradiated area is constantly in the shooting area. Modern systems make it possible to obtain images of the earth's surface and objects located on it with resolutions of the order of 1 m for overview and 0.3 m for detailed modes. The Sandia company announced the creation of a SAR for tactical UAVs, which has the ability to shoot with a resolution of 0.1 m in detailed mode. The resulting characteristics of the SAR (in terms of surveying the earth's surface) are significantly affected by the methods used for digital processing of the received signal, an important component of which are adaptive algorithms for correcting trajectory distortions. It is the impossibility of maintaining a rectilinear trajectory of the carrier for a long time that does not make it possible to obtain resolutions comparable to the detailed mode in the continuous survey mode, although there are no physical restrictions on the resolution in the survey mode.
The mode of inverse aperture synthesis (IRSA) allows synthesizing the antenna aperture not due to the movement of the carrier, but due to the movement of the irradiated target. In this case, we can talk not about the translational movement characteristic of terrestrial objects, but about the pendulum movement (in different planes), characteristic of floating craft swinging on the waves. This opportunity defines the main purpose of IRSA - detection and identification of marine objects. The characteristics of modern IRSA allow you to confidently detect even small objects, such as periscopes submarines. All aircraft in service with the US Armed Forces and other states, whose tasks include patrolling the coastal zone and water areas, are able to shoot in this mode. The images obtained as a result of shooting are similar in their characteristics to the images obtained as a result of shooting with direct (non-inverse) aperture synthesis.
Interferometric survey mode (Interferometric SAR - IFSAR) allows you to get three-dimensional images of the earth's surface. Wherein modern systems have the ability to conduct single-point shooting (that is, use one antenna) to obtain three-dimensional images. To characterize image data, in addition to the usual resolution, an additional parameter is introduced, called height accuracy, or height resolution. Depending on the value of this parameter, several standard gradations of three-dimensional images (DTED - Digital Terrain Elevation Data) are defined:
DTEDO.............................. 900 m
DTED1.............................. 90m
DTED2.............................. 30m
DTED3..............................10m
DTED4...............Sm
DTED5..............................1m
The type of images of an urbanized area (model) corresponding to different levels of detail is shown in fig. 3.
Levels 3-5 are officially known as HRTe-High Resolution Terrain Elevation data. The determination of the location of ground objects on images of level 0-2 is carried out in the WGS 84 coordinate system, the height is measured relative to the zero mark. The coordinate system of high-resolution images is not currently standardized and is under discussion. On fig. Figure 4 shows fragments of real areas of the earth's surface obtained as a result of stereo imaging with different resolutions.
In 2000, the American Shuttle, within the framework of the SRTM (Shuttle Radar Topography Mission) project, the purpose of which was to obtain cartographic information on a large scale, performed an interferometric survey of the equatorial part of the Earth in the band from 60 ° N. sh. to 56°S sh., having received at the output a three-dimensional model of the earth's surface in the DTED2 format. To obtain detailed 3D data in the US, the NGA HRTe? within which images of levels 3-5 will be available.
In addition to radar imaging of open areas of the earth's surface, the airborne radar has the ability to obtain images of scenes hidden from the observer's eyes. In particular, it allows you to detect objects hidden in forests, as well as those located underground.
Penetrating radar (GPR, Ground Penetrating Radar) is a remote sensing system, the principle of which is based on the processing of signals reflected from deformed or different in composition areas located in a homogeneous (or relatively homogeneous) volume. The earth surface sounding system makes it possible to detect voids, cracks, buried objects located at different depths, to identify areas of different density. In this case, the energy of the reflected signal strongly depends on the absorbing properties of the soil, the size and shape of the target, and the degree of heterogeneity of the boundary regions. At present, GPR, in addition to its military-applied orientation, has developed into a commercially viable technology.
Sounding of the earth's surface occurs by irradiation with pulses with a frequency of 10 MHz - 1.5 GHz. The irradiating antenna may be located on the earth's surface or located on board the aircraft. Part of the irradiation energy is reflected from changes in the subsurface structure of the earth, while a large part penetrates further into the depths. The reflected signal is received, processed, and the processing results are shown on the display. When the antenna moves, a continuous image is generated that reflects the state of the subsurface soil layers. Since, in fact, reflection occurs due to the difference in the dielectric constants of various substances (or different states of one substance), probing can reveal a large number of natural and artificial defects in a homogeneous mass of subsurface layers. The depth of penetration depends on the condition of the soil at the site of irradiation. The decrease in signal amplitude (absorption or scattering) largely depends on a number of soil properties, the main of which is its electrical conductivity. Thus, sandy soils are optimal for sounding. Clay and very moist soils are much less suitable for this. Good results are shown by probing dry materials such as granite, limestone, concrete.
The sounding resolution can be improved by increasing the frequency of the emitted waves. However, an increase in frequency adversely affects the penetration depth of the radiation. So, signals with a frequency of 500-900 MHz can penetrate to a depth of 1-3 m and provide a resolution of up to 10 cm, and with a frequency of 80-300 MHz they penetrate to a depth of 9-25 m, but the resolution is about 1.5 m.
The main military purpose of subsurface sounding radar is the detection of planted mines. At the same time, the radar installed on board an aircraft, such as a helicopter, allows you to directly open maps of minefields. On fig. Figure 5 shows images from a helicopter-mounted radar showing the location of anti-personnel mines.
Airborne radar, designed to detect and track objects hidden in forests (FO-PEN - FOliage PENetrating), allows you to detect small objects (moving and stationary), hidden by tree crowns. Shooting objects hidden in forests is carried out similarly to conventional shooting in two modes: overview and detail. On average, in the overview mode, the capture bandwidth is 2 km, which makes it possible to obtain images of 2x7 km of the earth's surface at the output; in the detailed mode, the survey is carried out in sections of 3x3 km. The shooting resolution depends on the frequency and varies from 10 m at a frequency of 20-50 MHz to 1 m at a frequency of 200-500 MHz.
Modern methods of image analysis make it possible to detect and subsequently identify objects in the received radar image with a sufficiently high probability. At the same time, detection is possible on images with both high (less than 1 m) and low (up to 10 m) resolution, while recognition requires images with a sufficiently high (about 0.5 m) resolution. And even in this case, we can talk for the most part only about recognition by indirect signs, since the geometric shape of the object is very strongly distorted due to the presence of a signal reflected from the leaf cover, as well as due to the appearance of signals with a frequency shift due to the Doppler effect that occurs in the result of leaves swaying in the wind.
On fig. 6 shows images (optical and radar) of the same area. Objects (a column of cars) invisible on the optical image are clearly visible on the radar image, however, to identify these objects, abstracting from external signs(moving on the road, the distance between cars, etc.) is impossible, since at this resolution information about the geometric structure of the object is completely absent.
The detail of the obtained radar images made it possible to implement in practice a number of features, which, in turn, made possible solution a number of important practical problems. One of these tasks is tracking changes that have occurred on a certain area of the earth's surface over a certain period of time - coherent detection. The duration of the period is usually determined by the frequency of patrolling a given area. Tracking of changes is carried out on the basis of the analysis of coordinate-wise combined images of a given area, obtained sequentially one after another. In this case, two levels of analysis detail are possible.
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| Fig. 5. Maps of minefields in three-dimensional representation when shooting in different polarizations: a model (on the right), an example of an image of a real area of the earth's surface with a complex subsurface situation (on the left), obtained using a radar installed on board a helicopter | |
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| Rice. Fig. 6. Optical (above) and radar (below) images of a section of terrain with a convoy of cars moving along a forest road | |
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The first level involves the detection of significant changes and is based on the analysis of the amplitude readings of the image, which carry the main visual information. Most often, this group includes changes that a person can see when simultaneously viewing two generated radar images. The second level is based on the analysis of phase readings and makes it possible to detect changes invisible to the human eye. These include the appearance of traces (of a car or a person) on the road, a change in the state of windows, doors (“open - closed”), etc.
Another interesting SAR capability, also announced by Sandia, is radar video recording. In this mode, the discrete formation of the antenna aperture from section to section, which is characteristic of the continuous survey mode, is replaced by parallel multichannel formation. That is, at each moment of time, not one, but several (the number depends on the tasks being solved) apertures are synthesized. A kind of analogue of the number of formed apertures is the frame rate in conventional video recording. This feature allows you to implement the selection of moving targets based on the analysis of the received radar images, using the principles of coherent detection, which is essentially an alternative to standard radars that select moving targets based on the analysis of Doppler frequencies in the received signal. The effectiveness of the implementation of such selectors of moving targets is very doubtful due to significant hardware and software costs, therefore, such modes will most likely remain nothing more than an elegant way to solve the selection problem, despite the opportunities that open up to select targets moving with very low speeds(less than 3 km/h, which is not available to Doppler SDC). Direct video recording in the radar range has also not found application at the present time, again due to high requirements for speed, therefore there are no existing models of military equipment that implement this mode in practice.
A logical continuation of improving the technique of surveying the earth's surface in the radar range is the development of subsystems for analyzing the received information. In particular, the development of systems for automatic analysis of radar images, which make it possible to detect, distinguish and recognize ground objects that have fallen into the survey area, is of great importance. The complexity of creating such systems is associated with the coherent nature of radar images, the phenomena of interference and diffraction in which lead to the appearance of artifacts - artificial glare, similar to those that appear when a target with a large effective scattering surface is irradiated. In addition, the quality of the radar image is somewhat lower than the quality of a similar (in terms of resolution) optical image. All this leads to the fact that there are currently no effective implementations of algorithms for recognizing objects in radar images, but the number of works carried out in this area, certain successes achieved recently, suggest that in the near future it will be possible to talk about intelligent unmanned reconnaissance vehicles that have the ability to assess the ground situation based on the results of the analysis of information received by their own airborne radar reconnaissance equipment.
Another direction of development is integration, that is, a coordinated combination with subsequent joint processing of information from several sources. These can be radars shooting in various modes, or radars and other reconnaissance equipment (optical, infrared, multispectral, etc.).
Thus, modern radars with antenna aperture synthesis allow solving a wide range of tasks related to conducting radar surveys of the earth's surface, regardless of the time of day and weather conditions, which makes them an important means of obtaining information about the state of the earth's surface and objects located on it.
Foreign military review No. 2 2009 P. 52-56
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