Su-27 AIRBORNE RADAR MODERNIZATION
Introduction
Su-27 belongs to the most advanced air superiority fighters of fourth generation. Main characteristics of Su-27 fairly exceed the parameters of the other air superiority fighters. It has proved its reliability and effectiveness through the numerous flight trials and training fights. In addition, Su-27 was highly estimated by foreign pilots, who had a chance to test the aircraft independently.
This aircraft is generally developed for being an air superiority fighter and fighter-interceptor aircraft. What is more, in the circumstances of visible ground or marine targets it has certain facilities as a fighter-bomber. Fulfilling such a role, the Su-27 carries bombs and unguided missiles. The radar sighting system (RLPK-27) is the most significant mean of detecting the air targets.
The weapon control system of the Su-27 aircraft consists of:
- airborne radar H001;
- optical-electronic aiming system;
- display information system;
- weapon control units;
- target identification system.
But the main information system, which defines the primary characteristics of the weapon control system, is the pulse-doppler radar H001.
H001 RADAR information
Design
Pulse-Doppler radar H019 is designed for:
► targets acquisition at short and medium ranges the with different speed and altitude;
► target tracking and corresponding information sending for the air-to-air missiles;
► air-to-air missiles launch zone computation and sending this information to the display system;
► target illumination after the missiles has been launched.
H019 consist of:
► antenna assembly;
► transmitting channel;
► receiving channel;
► synchronization system;
► fire control computer;
► weapon control units.
The H001 radar scheme
H001 Modernization Description
The upgrade version of H019 Airborne Radar will sufficiently improve the technical characteristics of the presented aicraft. By the replacement and modernization of the main functional units, an addition of the new radar modes (such as an air-to-surface mode) would be easily allowed. Considerable reliability enhancement of the radar system parts and its improved characteristics will increase H019’s radars life time up to 10 years. Thanks to such an alteration, additional prospects to further modernization are possible.
The first stage of the mentioned boost includes:
► High frequency receiver replacement with the upgraded version Н019-09R1;
► Frequency synthesizer replacement with the Н001-22R;
► Doppler filters and air target detection units replacement with the «MCPP».
The new high frequency receiver modules and synthesizer installations will increase detection range (for about 25-30%) of air targets.
At this stage, it is also possible to apply for the transmission of phase-manipulated signals, which can be used in air-to-surface radar operation modes.
The change of Doppler filters and air target detection units delivers new qualities to the narrowband Doppler signal and measurement system. This replacement will advance not just target detection, but also a selection of reflected target signals from noise, clutter and jamming alarms.
Thus, while operating with both high and medium pulse repetition frequencies, certain enhancement might be achieved for standard H019 radar air-to-air modes.
Overall, the first step of renovations is supposed to improve:
► target acquisition characteristics;
► electronic counter-countermeasures;
► reliability indicators.
At the second stage of the update, it is offered to build a completely new digital signal processing system, which would operate separately and include multi-channel wideband digital signal processor (WDSPU) and multifunction control processor (MCPU).
The complement of second stage radar system
► high speed data switch (DS);
► multi-channel wideband digital signal processor unit (contains the air target parameters estimation module ans digital control synthesis aperture module);
► multifunctional control processor unit;
► multifunctional display unit (designed for the indication of all existing new radar modes and consist of TFT panel, video processor and the interface card).
Besides the second stage of renovation, modernization of the other H019 radar units are granted:
► synchronization unit;
► antenna assembly.
Such alterations make possible to actualize advanced radar qualities in air-to-air modes and give a possibility to add the air-to-ground modes.
The immediate result of the second stage modernization will contain:
► real time ground mapping mode;
► the synthesis aperture mode;
► guidance to several air-to-air missiles with different targets simultaneously;
► the possibility of addition to the MiG-29 weapon control system modern air-to-air and air-to-ground guided missiles: Х-31А и Р-77;
► further improvement of the tactical characteristics;
► acquisition range (δц = 3 м² ) up to 90 km and 50 km (rear semi-sphere);
► radar reliability enhancement -- up to 40-50%.
The H001 upgraded radar Scheme
Upgraded microwave receiver H019-09R2
H019-09R2 unit is the upgraded version of the H019-09A units-a-parts of receiver channels of airborne radars H001.
The H019-09R2 is a 3-channel high sensitivity microwave receiver, which contains: 3 receiver modules, frequency converter, blanking unit and power supply units. Each receiver module includes narrowband and wideband receiver channels. Narrowband receiver channel is designed for the high speed air targets detection with the narrowband Doppler filters system, while the wideband receiver channel is designed for the high resolution radar modes realizing to detect low speed surface (ground or marine) targets.
Upgraded microwave generator unit the H001-22R2
The enhanced version of previously designed H001-22М microwave generator unit the H001-22R2 is the part of the transmitter channel of H001 airborne radar.
It includes a microwave generators assembly and a power supply assembly, which can be repaired by simple faulty modules replacement.
The H001-22R2 is designed for CW and pulse microwave signals as well as a synchronization signals generating. According to the control information from the central computer, the digital control unit applies different types of modulation to the generated CW or to pulse signals, as well as receives the service information from internal modules in order to send it to the central computer.
Digital signal processor unit BCO-R
Upgraded analog of the BCO-М, BCO-P units
The digital signal processor unit (DSPU) is designed for the installation in low frequency receiver Н019-03 for modernization of H001 airborne radars. DSPU realizes the multi channel digital target acquisition algorithm using the digital Doppler filters, logical block and system computer interface block.
The air target acquisition module, the first part of DSPU, provides full compatibility with the original H019 target detection units and has comparatively better characteristics such as sensitivity (as a part of the low frequency receiver) Doppler filters side lobes level, reflected signal detection stability and reliability.
Other parts of DSPU are the long range detection module and digital synthetic aperture module, which can be installed in parallel with the existing DSP module. Thanks to the long range detection module, upgraded radar could improve the target detection range up to 1.3-1.5 times (comparatively to its standard characteristics) operating in the new long range target detection mode.
Digital synthetic aperture module allow to add to the airborne radar the air-to-surface modes, such as ground targets searching with the Doppler beam sharpening and side-looking mode with the synthetic aperture algorithm.
Multifunctional processing system «Oreadna»
Multifunctional processing system is designed to provide a new operational modes for the fighter upgraded weapon control system.
It provides:
► information receiving and its collecting from a variety of sources and further data sending to a multifunctional display (МФИ-27);
►processing of an aperture synthesis algorithms and Doppler beam sharpening algorithms while a radar operation in surface search modes;
► moving target detection and tracking algorithms processing while radar operates in the surface search modes;
► processing the algorithms of the targets destination and the computation of launch zones for the new types of weapons suspended.
The multifunctional processing system contains a processor block, peripheral unit, interface unit, ADC-DAC unit and a power supply unit.
The specialized computer unit (SCU «Oreadna») is implementated to control the radar in ground search operational mode. SCU «Oreadna» is the new generation computer unit which is designed with the use of open architecture principle, based on the real-time CPUs and VPX system strip, which allows connection to the computer of additional devices (boards) for various purposes.
Multifunctional display MFI-27
Multifunctional display MFI-27 is designed for the installation on the cockpits dashboard of aircrafts and helicopters such as Su-27 and MiG-29 fighters. LCD "5x4" provides a comfortable work of a pilot at any light conditions in the daytime. Active TFT matrix has high resolution characteristics plus wide viewing angles and allow to display high quality graphics even under the sunny light.
Control panel is equipped with the automatic brightness adjustment system. In addition, 20 multifunctional knobs and 2 potentiometers are placed on the control panel. At the end, to load a new software to MFI-27 is possible through the external connector.
Bus commutating block Н001-04МR
Bus commutating block Н001-04МR is designed for operating in the upgraded H001 radar in order to provide the commutating of the MII, MIII, MIV digital buses and the other various control signals to the fire control computer “Ц100.03.03” and to the multifunctional processing system «Oreadna».
Н001-04МR consists of an interface boards with build-in high frequency switches together with buffers and control units.
The upgraded H019 radar units location scheme
The upgraded H001 radar units location scheme
Guided air-to-air missiles
Medium range air-to-air missiles R-27 is designed for the destruction of all types aircrafts, helicopters and drones as well as a high speed low altitude cruise missiles. R-27 may be launched to the targets at the long medium and short distances from any directions in all weather conditions. It is proved to be an effective weapon even in case of application of electronic countermeasures.
R-27 is assembled in different performances, which differ mainly by the type of homing devices and engines.
For example, R-27R – is the R-27 model with semi-active homing device. Its launch range may reach up to 80 km, which means that the combined guidance system is inertial and semi-active homing at the final part of the flight to target.
Simultaneously, R-27T is the R-27 model with the infrared homing device. R-27ER and R-27T are the R-27 models with semi-active and infrared homing devices, respectively. Additionally, renovated engine has the maximum launch range of R-27ER. In comparison with the basic model R-27R, R-27ET’s abilities are increased up to 120 km and are distinct by the large length and mass.
The R-27 missiles are capable to attack the targets sent from any direction, when targets altitude varies from 20 m to 27 km with the maximum target speed up to 3500 km/h.
R-77 is the medium range missile with the radar active homing device. It is capable to eliminate the target at the speeds up to 3500 km/h and on the altitude from 20 m to 27 km.
The acceptable altitude difference between the target and the interceptor is 10 km.
Guided air-to-surface missiles
The guided air-to-surface missiles are often named as a high-precision weapon. They are usually divided into a few classes according to the guidance and target type.
Specifically, they may be classified in air-to-surface missiles with laser guidance, TV guidance and air-to-radar or antiradar missiles.
The most common and shared air-to-surface missile with laser and TV guidance (two different versions) previously was the Kh-29L, Kh-29T missiles. It could be applied for destroying shielded surface targets as well as bridges and different types of marine targets. The maximum launch range is about 10-12 km with a launch height from 200 m to 5 km .
Among the most successful anti-radar missiles, Kh-31P may be defined as a leading one. It was designed in 80th to destroy primarily the ground-to-air missile control radar systems such as US «Patriot». Equipped with the passive homing device and with the smart guidance anti ECM algorithms, it is able to hit any hostile surface radar system. The Kh-31P homing device can operate in different modes such as automatic target search, locking on the target. and external control mode.
The Kh-31P can accelerate up to 4700 km/h. Its launch range may vary between 5 and 100 km at the altitude from 50 m to 15 km.
The acceptable altitude difference between the target and the interceptor is 10 km.