Electronic Enthusiast News: As we all know, military avionics has very strict requirements on semiconductor ICs, electronic components, connectors and electronic systems. At present, the relatively well-known major military avionics suppliers ADI, TI, Xilinx, Infineon, Altera, MicroSemiconductor, etc. In order to discover the main technological context and business opportunities in the future, it is necessary to sort out several key new developments in the field of military avionics, including navigation systems, displays, COTS and electronic structures, in order to provide readers with useful references.
New development of navigation system
The navigation of military aircraft and airborne weapons is still dominated by GPS navigation systems and inertial navigation systems, and navigation systems are developing toward more sophisticated, lighter, smaller, and lower prices.
1 The main development direction of GPS is to improve its anti-interference ability
The United States launched the first GPS 2R global positioning system satellite on July 23, 1997 from Cape Canaveral with the 0 Delta 02 (Delta 2) rocket. It is the 42nd satellite in the Navstar series to be launched.
A previous 2R satellite was damaged by the explosive surface of the launch vehicle during launch in January 1997. The GPS 2R satellite was developed by Lockheed #Martin and weighs 2030 kg. The 2R satellite and its 18 satellites will be able to operate autonomously for 6 months without ground correction.
The 2R batch has a larger margin and a new cross-link distance measurement capability to improve accuracy. Once 6 ~ 8 new 2R satellites are put into operation, the accuracy of GPS navigation will be improved from the current 10 meters to better than 6 meters.
The first Navstar GPS satellite was launched in early 1978. The development of the Navstar satellite has gone through the first batch, the second batch, the 2A batch and the current 2R batch. From about 2002, a newer 2F satellite manufactured by Boeing will be launched.
The next four years will be the peak period of solar activity, and GPS and its applications will be developed during a particularly mild period of the sun. Compared with the output power of 2 / 2A satellites, the output power of 2R may be reduced by 2 to 4 decibels The output power between the satellites differs by at most 2 dB. Therefore, the United States is very worried that the peak solar activity will cause the ionosphere to fluctuate and cause navigation errors, or even cause the GPS signal to be interrupted. In particular, it is concerned that the GPS signal received by the aircraft during the approach may be damaged.
In addition, as aviation's reliance on GPS has increased, military and civil aviation users are increasingly concerned about unintentional interference and intentional interference with the system. The military is particularly concerned about the anti-jamming capability of GPS. The enemy will interfere with GPS, trying to stray incoming missiles, and the closer the weapon is to the target, the stronger the jamming signal it will fight.
An attempt by the US Defense Advanced Research Projects Agency (DARPA) to improve GPS anti-jamming is focusing on the development of an atomic clock small enough to fit in a new receiver. The current atomic clock is much larger than the fiber optic gyro (FOG) inertial navigation / GPS component under development, but it is expected to be small in the near future. The precise time provided by the atomic clock in the missile warhead will accelerate the GPS to intercept the satellite again after the signal is interrupted. There are atomic clocks that can pick up satellite signals in less than 1 minute, while it can take a few minutes without an atomic clock.
Other methods to improve anti-jamming capability are the use of adaptive antennas and new materials. The GPS receiver requires an antenna with a diameter of 0.8 to 1.2 meters for the use of better adaptive zero manipulation interference technology. For missiles, this size is obviously too large. Therefore, DARPA believes that the antenna embedded in the missile skin, that is, smart skin is a good way to solve this problem.
Russia displayed a GPS jammer at the Moscow Air Show in 1997 to prevent the reception of navigation satellite signals at 4 frequencies. The jammer weighs 10 to 12 kilograms, and the transmitted power is sufficient to suppress the normal operation of the receiver within hundreds of kilometers. It has 4 fixed frequency oscillators, and these 4 frequencies are used by the signals transmitted by GPS and GLONASS. The jammer's power amplifier has 4 watts of power in the 1200-1650 MHz band. The U.S. Air Force will purchase eight jammers for analysis at Eglin Air Force Base and find ways to deal with it.
2 Development of inertial navigation and smaller and lower price
The advantages of fiber optic gyroscope are small size, light weight, low cost and high reliability, which is very suitable for use in low-cost combined GPS-INS for precision guided weapons. Fiber optic gyro (FOG) has begun to challenge the ring laser gyro (RLG). FOG has replaced RLG in some less important civilian and military applications, where a gyro drift rate of 1 degree / hour is acceptable. The US Air Force is considering replacing the rotating mass rate gyro used in many military autopilots with a smaller, more reliable FOG. The FOG produced by FTC has been installed on the F-15 aircraft for a test flight.
The United States currently develops FOG companies mainly including Leaton and Honeywell. The Boeing 777 aircraft uses a backup navigation system provided by Honeywell with four FOGs, called the auxiliary attitude atmospheric reference device (SAARU). The FOG performance is within 1 degree / hour. Honeywell has produced this level of FOG since 1992, and has delivered more than 1500 fiber optic gyros.
Leeton Industries uses FOG's LN-200 inertial reference device now has more than 40 different applications, including aircraft, missiles and drones. The basic LN-200 inertial reference device, which includes three FOGs and three small linear accelerometers micromachined on a silicon chip, has a diameter of 8.89 cm, a height of 8.64 cm, and weighs less than 0.726 kg. LN-201 is a slightly heavier type, used for AMRAAM air-to-air missiles after reassembly. The Leighton LN-210 has been selected for the RAH-66 helicopter. This helicopter will be equipped with two FOG inertial reference systems and a Leighton inertial navigation system using RLG.
DARPA's ongoing GPS guidance component (GGP) project has selected two company groups for development in the second phase: Leeton / Rockwell / Collins and Honeywell / Tempo Navigation. The FOG developed by Litton and Honeywell for GGP will have an accuracy of 0.01 degrees / hour and a navigation accuracy of 1 nautical mile / hour. The performance of the entire system will also be improved by combining the inertial and GPS navigation satellite signals. Both Collins and Trimble ’s GPS receivers will be 12-channel devices.
The goal of this project is to reduce the size of the GGP system to 1,640 cubic centimeters, its weight is only 3,118 kilograms, and the mean time between failures (MTBF) is 20,000 hours, three times larger than the MTBF of the current RLG inertial system. The power consumption is only 30 watts, which is particularly important for drones and missiles. The mass production cost of the combined inertial / GPS system is reduced to about $ 15,000, which is about one-third of the system with similar performance using RLG. To reduce the size and cost of GGP, the two companies will use accelerometers fabricated on silicon chips by micromachining technology. Honeywell ’s micro-accelerometer will be supplied by Allied Instruments ’instrumentation system. Litton ’s micro-accelerometer is self-developed and used in the inertial navigation system of its current AMRAAM missile. DARPA is expected to complete this work in the spring of 1999.
Although the military may adopt GGP first, civil aviation will follow suit. Small size, light weight and low cost may open the way for many general aviation aircraft to be equipped with first-class navigation equipment. If the combined inertial / GPS of Litton and Honeywell can achieve a price of $ 15,000, then this will expand the civilian market of the system to include short-range aircraft and twin-engine general aviation aircraft. Similarly, these systems can greatly increase the precision of precision-guided weapons by making them less susceptible to localized interference by the enemy on GPS signals. A system equipped with 0.01 degrees / hour FOG will allow the GPS signal to be lost for 10 minutes and still be within 30 meters of its intended target.
According to the contract signed with the Air Force, Litton is developing a 0-precision FOG0 whose goal is to increase the FOG accuracy by roughly 10 times, almost to 0.001 degrees / hour. Honeywell is using its own funds to conduct research to achieve the same goal.
Although rotating mass gyros have largely been replaced by RLG, experts have different opinions on whether RLG will face the same fate. For example, Honeywell ’s inertial system that uses a small RLG has recently been selected for the “Joint Direct Attack Bomb†(JDAM), which shows that RLG has considerable vitality. However, the consensus of experts is that the future of "light top" is bright. However, one day, optical gyros will be challenged by microelectronic gyros that manufacture vibration quality on chips in lower precision applications. Draper Laboratories has been the first to develop this technology, and other companies such as Litton and Rockwell are also conducting research in this area.
DARPA is already advancing the development of very low-cost FOG / INS / GPS. In 1997, it has signed a contract with the industrial sector to develop this micro-electromechanical navigation device for infantry. These small devices will be processed on a micro-scale, with the goal of selling the entire system at $ 1,200 and consuming less than 1 watt.
Rockwell has delivered the first navigation processor to Alliant's Outrider drone. This navigation processor uses one of Rockwell ’s smallest inertial sensors on the market, a digital quartz inertial measurement device (DQI), and uses a GPS receiver from the UAV ’s automated launch and recovery system. signal of. DQI is the first generation of MEMS sensor for inertial sensitivity, which is produced in batch from a quartz substrate. This simple, small, and reliable DQI uses a vibrating quartz sensor and is suitable for smart weapons, missiles, and drones.
The American Irvine Sensor Company is developing an inertial navigation system with a size like a cube of sugar. The system is based on a customized micro-machined gyro, called Silicon MicroRing Gyro. US Navy officials want to use this 2 cubic centimeter system for sonar buoys and related applications. Micromachining uses semiconductor manufacturing methods to manufacture sensors and structures with feature sizes in microns. MicroRing uses low-cost silicon and metal structures while measuring movement along several axes. The U.S. Navy stipulates for it: a dynamic range of 100 decibels, 10 milliwatts of power consumption and 0.5 flying capacitors.
Here you can find the related products in Magnetic Light Accessories, we are professional manufacturer of Magnetic Track 1M, Led Rail Track , Led Track Rail, Magnetic Led Light. We focused on international export product development, production and sales. We have improved quality control processes of Magnetic Light Accessories to ensure each export qualified product. If you want to know more about the products in Magnetic Light Accessories, please click the product details to view parameters, models, pictures, prices and other information about Magnetic Track 1M, Led Rail Track, Led Track Rail, Magnetic Led Light.
Whatever you are a group or individual, we will do our best to provide you with accurate and comprehensive message about Magnetic Light Accessories!
Magnetic Light Accessories
Magnetic Track 1M,Led Rail Track,Led Track Rail,Magnetic Led Light
Guangdong Decosun Lighting Technology Co.,Ltd , https://www.decosun-lighting.com