Radar and Auxiliary driving
Radar and Auxiliary driving
Radar navigation
The radar is an electronic device that uses radio to detect, range and other functions. After the radar emits the electromagnetic wave, the target is irradiated, and the reflected wave is received, and the distance between the target and the emission point, even the radial velocity, the azimuth, the height, and the like is obtained by the property of the electromagnetic wave and a certain calculation. This paper mainly discusses the development of radar and its basic principle. During World War I, in order to guard against metal objects, such as air-planes, the British military is intended to study a technology that can detect metal objects in the air, that is, radar technology. During the Second World War, radar technology has been developed to address basic modern wars, such as surface-to-air, air-to-surface, air-to-air, and enemy-to-face identification. After the Second World War, due to the high potential and multi-function of the radar application, single pulse angle tracking, pulse Doppler signal processing, synthetic aperture and pulse compression high resolution, combined with the combination system identified by the enemy, and combining with the automatic fire control system of the computer, Terrain avoidance and terrain following, active and non-source phase arrays, frequency agile, multi-target detection and tracking. With the development of the micro-electronics field, the content of the radar and the content of the technology are constantly extending, and the detection methods of the radar have been developed from a single detection way to the use of infrared light, ultraviolet light, and laser and other optical detection means.
Radar and auxiliary driving
Today, radar navigation is mostly used for military, existing marine navigation radar, warship navigation radar, aircraft navigation radar, and civil radar is less involved in navigation. Satellite navigation is now a popular civil navigation system. In fact, the two navigation functions are refined, and the navigation of the satellite is applicable to the large-scale and relatively stationary navigation, and the radar navigation can better cope with the sudden situation, so as to obtain more accurate data, such as distance, distance change rate, azimuth, height and the like. In the daily life, the[1] global satellite navigation system (GPS system, Beidou system) really can handle the vast majority of situations, but the effect of the global satellite navigation system (GPS system, Beidou system) is not so good in a small range and a variable environment. Nowadays, radar is applied to the auxiliary function of automobile, such as[2] reversing radar. The reverse radar is a safety auxiliary device for the automobile in the vehicle or in the reverse direction, which is composed of a simple ultrasonic sensor, a controller and a display, and functions when the car is parked. The small-sized radar has been developed for many years and has a high degree of popularization in the market. The currently existing navigation radar is mostly used in military, such as the[3] ship navigation radar, mainly to cope with the dangerous navigation environment, such as the night driving, the fog day driving, the narrow water channel and the coastal navigation, the main function is to prevent the impact. if such a radar is applied to a civilian vehicle, it is first possible to consider designing on-board auxiliary radar, such as a signal transmitter, a sensor, a receiver, a display, and the like, the vehicle or obstacle in the driving is displayed on the vehicle-mounted central console display screen, the driver can obtain the obstacle or danger information in the vicinity of the vehicle and send an alarm or a voice prompt when reaching a certain danger threshold, thereby reducing the accident rate, and the safety is improved under the condition that the road condition is not good. It is worth mentioning that, unlike the signal frequency used by mobile communication, because the millimeter-wave radar has a very high frequency, there is a clear Doppler shift phenomenon, and the speed of the moving object can be captured. In addition, we face a number of problems, such as the fact that the object of different materials is not exactly the same as the electromagnetic wave emitted by the emitter, and by this nature, we can even judge the material of the object type and even guess what kind of object it is. Second, the road condition is much more complicated than the ocean, and how to improve the radar efficiency and accuracy and to improve its anti-interference ability is the focus and difficulty. It is envisaged that the scope of reconnaissance in conventional car driving can be expanded and more accurate, more comprehensive information data can be obtained and can also be used as a basis for future vehicle automatic driving. The previously existing vehicle-assisted driving device, such as a conventional rear-view mirror, a parking radar, and the like, is limited in its application range to the periphery of the vehicle body and is easily blocked. In recent years, due to the rapid development of the Internet, many fields have become more and more dependent on the Internet, and if the private radar network can be realized, the experience of the[4] meteorological radar networking can be learned, the on-board civil radar is connected, and even the traffic light dynamic information is added, We can obtain more dynamic road condition information than the traditional satellite map, and make more accurate and effective path planning according to this dynamic information. The private car-mounted civil radar can also incorporate the function of the service recorder, and each trolley can back up the radar information in the public security organ, and can quickly lock the target according to the radar information, and the function can be used for criminal tracking and monitoring and the like.[5] The military radar IFF system can also be used in the future auto-driving system of the vehicle and the vehicle built-in radar to carry out the inquiry and response, so as to coordinate the path planning, order of driving and so on. by using the technology, the automobile can be automatically driven. In the future, the auto-driving automobile is bound to be universal, how to improve the safety performance, and realize the production and control cost is the most pressing three key problems nowadays.
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