China's stealth drone with a dark sword test DWL002 radar
High-precision measurement technology and communication transmission technology, to achieve the goal of accurate positioning. The system relies on GPS or other positioning satellite positioning technology (including China's "Compass" system), and the detection accuracy and time synchronization inseparable. The center of the surveillance system and other surveillance station terminal must maintain accurate time synchronization, or time difference calculated does not make sense. There are many ways to achieve time synchronization, the best way is to have received all the reconnaissance satellite receiving station (such as China's "long river II" systems have this capability, precision 10-6 seconds; the next step such as "Compass" system global network is successful, it will provide more accurate timing ability) of the grant, this approach not only high accuracy but also to achieve global coverage. Reported the actual accuracy of the system can reach 2% ~ 3% (CEP).
Ability to identify a target
Obtain the target location information in the same time, the carrier frequency can be targets, signal intelligence and other forms of information, through its own radiation and the radiation source database platform to achieve recognition.
Stealth technology has changed the method of air combat, in particular, stealth aircraft and precision guided weapons, the combination of greatly improved operational efficiency, changing the offensive and defensive strategic balance. The development of anti-stealth technology and weapons systems have become an important and urgent task, and anti-stealth research or the development of stealth technology and the driving force of a stimulus, but also check to verify the performance of their indispensable weapons and stealth means.
DWL002 passive detection radar system is a can of air, ground and sea targets to locate, identify and track the electronic intelligence detection system, which can be used as a passive three-dimensional radar, range up to 500 km. It is a strategic and tactical electronic intelligence and passive surveillance systems. Itself does not radiate electromagnetic signals, but the use of external non-cooperative (ie radiation and radar, "do not take the world", there is no direct relationship between coordinated operations) of the radiation source to detect and locate. Difficult to deal with active radar stealth air targets, while the ears of the system are sharp-eyed soul, able to detect the target even if it is issued by weak or electromagnetic transient electromagnetic signal reflected signals, immediately to targets on the radar screen visible. The layout of the system is usually composed by the four sub-stations: the main station as an electronic warfare center, the analysis and processing center, generally located in the central area, the other three signal receiving stations are located in the surrounding areas, round or curved layout to the main station the layout of the center circle, the system started after deployment, the distance between station and station 50 km. Located in front of the terminal to capture electromagnetic signals to the target immediately after the signal sent to the Electronic Warfare Center, station, central station using multi-directional cross-cutting and other methods to detect the location of targets, the target height of the signal captured by the receiving station to determine, to coordinate the target location.
When the system is deployed in place, according to the command center of the command, simultaneously on land, sea and air search for the passive early warning and reconnaissance. Invisible to the radar target detection, for example, when the target appears, it will certainly be passing through the airspace of the various types of electromagnetic waves, including military radar, microwave communications, civilian radio broadcasting, television transmission of civil, civil microwave communications, the Mobile phone base stations and other class a certain perturbation signal, which is like the calm water in the flying swallow the water after grazing will have a slight ripple, will cause some signal reflection. DWL002 is able to receive and analyze the master of weak electromagnetic signal reflection and analysis of immediate settlement through the center of the computer calculated the corresponding data, thereby to determine the source of the coordinate of the location of signal reflection parameters, and then, through the data link or other information transmission channel, these parameters are passed to one's own anti-aircraft missile units on the ground or air forces, resulting in the most appropriate time to get the opportunity to attack the enemy's stealth targets.
Allegedly, the Chinese used to test DWL002 target the enemy capability to detect stealth simulation goal is to just show up in recent years, cross-section of radar reflectivity is less than 0.01 square meters of "Dark Sword" stealth unmanned test machine. Based on the data, this detection system can accurately identify and determine the location of the air properties stealth targets, and high positioning accuracy, which can be with my air field air defense forces to use.
If you deal with other non-stealth target, China DWL002 more at ease.
In addition to the battlefield as a general early warning and reconnaissance tasks, all of the other effect is the passive radar for air defense surveillance radar main, reduced exposure to the electromagnetic characteristics of other radar and location opportunities for each other in this area of electronic surveillance without power and return, this role is very great significance! United StatesAir ForceIn recent years, the war, why can often play a large exchange ratio of air superiority? It's tactical stealth aircraft are often the first to use pre-ground surveillance radar system a good clean out, so that the other types of radar in the absence of early warning aircraft and air in the case of the blind can not command a decent state of air combat, the aircraft can take off only by virtue of their capability to detect conflicts, often only were bashing, it is impossible to obtain any record!
The system not only has excellent performance of anti-stealth, and not because of its own to any electromagnetic radiation, it can be against enemy electronic jamming and anti-radiation missiles to destroy the survival ability. Passive radar system eliminates the need for expensive high-power transmitter, transceiver switches and related electronic equipment, making the system significantly reduced manufacturing and maintenance costs, lower life cycle cost, and time-domain all-weather and all work effectively.
The current development status
Currently, there are many countries interested in the application of passive detection technology. • Lockheed Martin is the first one of the companies involved in the field, allegedly relying on television and radio transmitters, the passive detection range of the system to 220 km.
U.S. Department of Defense and the Defense Research Projects Agency in advance the University of Washington, Georgia Tech University and other universities and companies such as Raytheon, have carried out research in this field. In Europe, France also carried out the corresponding technical studies, demonstrated a prototype system of Italy, the UK is studying the passive coherent radar and "cellular" radar (Celldar), Russia and Ukraine developed the "armor" radar, the Czech Republic has developed a well-known The "Villa"-E Passive Radar and export many countries.
Stealth aircraft in the face of a direct threat to the United States and, therefore, special attention to anti-stealth technology research. With the exception of Southwest Research Institute developed DWL002 electronic devices, but China has also successfully developed the YLC-20 measured bistatic passive radar system, to and positioning, both of the radar function is almost, but DWL002 something more advanced. Same resonant radar detecting stealth targets are also built in 2001, up to 2,000 km from its role, in addition, said China has also developed a dedicated to detecting stealth aircraft, JY-27 solid-state VHF Radar, to detect not only more effective stealth target, and to anti-radiation missile attack.
As the saying goes, there must be a spear, shield, the development of stealth technology in today's world also gave birth to more anti-stealth technology. Now or in development initiatives and other means of anti-stealth technology also includes the long-wave or millimeter wave radar, carrier-free ultra-wide band radar, laser radar and infrared detection systems, passive radio frequency detection technology, Earth's magnetic field variability detection technology.
To fight against stealth aircraft, they must take various measures and means comprehensive. Reliable anti-stealth detection / attack system, the key is to form a different principle and the complexity of the work of different wavelengths on the sensor network. An important part of this network includes not only the sensor itself, but also on the different sources of data collection, processing, correlation and display process. In addition, in order to achieve the required high detection probability of interception system to provide precise target data, the location of the sensor (not only to the territory along the border and deployed in depth, including air, space guard) is also critical. Therefore, the future of the anti-stealth detection system, is likely to be land, sea, air, space an integrated system, the development of radar, passive detection, perhaps the key point.
China DWL002 passive detection radar system is the world's most advanced anti-stealth aircraft's radar system, its main performance is better than similar foreign radar, therefore, expected that the system will be a lot of the same stealth aircraft threats facing the country of choice. (Guang-Wen Chen)