In the increasingly important stealth and electromagnetic compatibility (EMC) technology, the role and status of absorbing materials are very prominent, and they have become a magic weapon and "secret weapon" for electronic countermeasures in modern military. Its engineering applications are mainly in the following aspects.
1 stealth technology
Coating absorbing materials on various weapons and military facilities such as airplanes, missiles, tanks, ships, warehouses, etc. can absorb reconnaissance radio waves and attenuate reflected signals, thereby breaking through enemy radar defenses. This is a kind of anti-radar reconnaissance. A powerful method to reduce the weapon system from being attacked by infrared guided missiles and laser weapons. For example, due to the use of absorbing materials in the American B-1 strategic bomber, its effective reflection cross section is only 1/50 of that of the B-52 bomber. The absorbing material can be used on the fairing of the 0H-6 and AH-1G Cobra helicopter engines. The infrared radiation of the engine is reduced by about 90%.
2 Improve the electromagnetic compatibility performance of the whole machine
The false signals generated by the reflection of electromagnetic waves by the aircraft fuselage may lead to false interception or false tracking of highly sensitive airborne radars; when several radars on an aircraft or a ship are working at the same time, the crosstalk between the radar transmitting and receiving antennas is sometimes very serious , The jammer on board or on the ship will also interfere with the radar or communication equipment on board... In order to reduce such interference, magnetic shields with excellent performance of absorbing materials are commonly used abroad to improve the performance of radar or communication equipment. For example, absorbing materials on the fuselage of radar or communication equipment, antennas and all surrounding interferences can make them more sensitive and accurate to find enemy targets; coating absorbing materials on the surrounding walls of the opening of the radar parabolic antenna can be Reduce the sidelobe's interference to the main lobe and increase the distance of the transmitting antenna, and the receiving antenna can reduce the interference of false target reflection; the application of absorbing materials in the satellite communication system will avoid the interference between the communication lines and improve the satellite The sensitivity of the carrier communication machine and the ground station, thereby improving the communication quality.