The United States is the country with the largest number of early warning aircraft in the world. There are 236 E-3 early warning aircraft, and 139 E-2 early warning aircraft, with a total of 175 , which is more than twice that of China and Russia. However, unlike the phased array formation of main fighter aircraft and warship radars, the US early warning aircraft radar is still mainly mechanical scanning. Although E8C's AN/APY-3 is a phased array radar, it is mainly used for ground detection and is not considered a real early warning aircraft. Although the E737 phased array radar early warning aircraft "co-developed" by the United States and Australia, the US military is not equipped.
E737 Early Warning Machine
But the backward scanning method does not mean that the performance of the US Early Warning Machine is low, but the actual situation is exactly the opposite.
E3 early warning machine is modified from Boeing 707 civil passenger aircraft. Its AN/APY-1 pulse Doppler early warning radar works in the S band and uses a flat-panel gap array antenna. The waveguide gap array is to groove the surface of the waveguide material responsible for microwave transmission, forming many gaps, allowing electromagnetic waves to radiate out through these gaps, because the waveguide gap looks like it is opened on a flat plate, this kind of antenna is called a flat plate gap array antenna. The AN/APY-1 radar can track about 600 targets at the same time and guide the fighter to intercept 100 of them. But this is just data from early models of AN/APY-1 radar. It has been upgraded many times later, and its processing power has long been different. It is conservatively estimated that it can now lead to intercept 200 targets, and the number of tracked targets has at least doubled, almost reaching the physical limit of the flat-slit gap array antenna. Therefore, the comprehensive performance of the E3 early warning aircraft is only higher than that of my country's KJ 2000, although the latter uses an active phased array early warning radar.
E3 early warning machine radar has a rotating radome with a diameter of 9.4 meters and a thickness of 1.8 meters
Let's look at E2 early warning machine . Its latest model E2D has been upgraded to an APY-9 early warning radar. This is a Yagi phased array radar that works in the decimeter band, and uses a detection method that combines mechanical scanning and electronic scanning. Yagi antenna The full name of is Yagi Uda antenna. The name comes from the surnames of the two inventors and was invented in the 1920s. The Yagi antenna consists of multiple metal pillars, with a wide and high profile, which is easy to achieve high gain and narrow beams. It is especially suitable for use as an E2 carrier-based early warning aircraft radar with small internal space and wide working wavelength. APY-9 forms a Yagi phased array antenna by reasonably adjusting the size of Yagi antenna and the spacing of the radiation units. phased array antenna beam pointing is flexible, solving the disadvantages of the difficulty of beam adjustment in Yagi antenna.
E2D Early Warning Machine APY-9 radar has two rows of 18 units Yagi antennas compactly arranged on its disc radome
AN/APY-9 radar in the key sector and pitch direction at azimuth 120°, and mechanical scanning is performed at all 360° azimuth. The active phased array radar fused by AN/APY-9 uses silicon carbide transceiver components, which is 60% larger than the previous generation of APS145 radar, and the target detection distance of RCS is 3 to 5 square meters can reach 500km. In addition, E2D also uses digital receivers and digital beamforming, which is second only to , 500 , and is one generation ahead of 500 in terms of components. Finally, E-2D also integrates infrared search and passive detection systems, which significantly improves the ability to discover stealth targets.
In the face of E2D using silicon carbide components, the KJW 500 has no advantage
To sum up, E2D has exceeded the KJW 500 in terms of component level, processing capacity and detection methods, and the degree of digitization is also very close, and it is only slightly behind in the scanning system. It is not an exaggeration to say that the comprehensive performance is comparable to the KJW 500.
With the above analysis, it is easier to understand the five reasons why American early warning aircraft are still mainly mechanical scanning:
1. Compared with fighter aircraft, the active phased array radar detection distance of early warning aircraft is limited. The detection azimuth angle of the fighter radar is only 60 degrees, while the detection azimuth angle of the early warning aircraft, especially the active phased array radar, is 360 degrees. The task of the early warning aircraft is to detect, track and command and guide, rather than lock. Therefore, it is impossible for the active phased array radar of early warning aircraft to double the number of fighter aircraft. It would be great to be able to double the number of 20-30%.For example, the detection distance of the E3 early warning aircraft is 400 to 450 kilometers, while the visual distance of the active array early warning radar is 500 to 550 kilometers.
2. The detection performance of active phased array early warning radar on stealth targets has not been qualitatively improved. was originally limited to the increase in the visual range of active phased array early warning radar, and the effective detection distance for stealth targets, especially the stable tracking distance, has not increased in proportion, because stealth targets like F35 are different from small targets, but are targets whose reflected energy can undergo huge changes. It is discovered that it is far from tracking. In this way, the difference between traditional mechanical scanning early warning radar and active phased array early warning radar on stealth target detection effects is minimal. The radar reflection characteristics of
F35 are different from those of small targets (the picture comes from Dragon Dream Network)
3. The US military's system is very strong, which can greatly make up for the shortcomings of mechanical scanning radar. The United States has launched more than 1,700 low-orbit communication satellites into space through the "Star" program. They can not only achieve near-real-time transmission of battlefield information, but also directly conduct condescending observations, so that early warning aircraft in the air may no longer be needed in the future battlefield. In addition, the U.S. military's drone and data link are also very powerful.
The US "Starlink Plan" will launch 42,000 low-orbit communication satellites
4. The US early warning aircraft has formed a huge scale and is in good condition. The large-scale replacement of radars is very expensive, so there is no need for this. now costs nearly tens of millions of active phased array radars for fighters, not to mention early warning aircraft. The cost of fully replacing the radar of 175 early warning aircraft will be astronomical, but the detection performance will be limited.
5, attempting to use new concept radar to establish absolute technological advantages again. Even if the US early warning aircraft is replaced with an active phased array radar, it cannot change the relatively backward situation compared with the digital array radar of of my country's Air Police 500. It is better to wait for the new concept radar under development to mature and complete the comprehensive upgrade in one step. The United States is now specializing in quantum radar and has made a lot of investments, which has reliable detection effects on stealth targets.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-