What Are the Different Types of Remote Sensing Jobs?

The remote sensing system is composed of various subsystems of platform, sensing, receiving, and processing applications. It is responsible for the entire process of collecting, transmitting, correcting, converting, and processing the electromagnetic wave radiation of the detection object, that is, converting the electromagnetic wave characteristics of matter and environment into images Or digital form. The remote sensing system is mainly composed of the following four parts: information source, information acquisition, information processing, and information application.

The term remote sensing comes from the English "Remote Sensing", which is literally translated as "distant perception", which has been translated into remote sensing for a long time. Remote sensing is a comprehensive earth observation technology developed in the 1960s. Since the 1980's, remote sensing technology has made great progress, and the application of remote sensing technology has become increasingly widespread. With the continuous progress of remote sensing technology and the continuous application of remote sensing technology, remote sensing technology in the future will play an increasingly important role in China's national economic construction. There are two broad and narrow interpretations of the scientific meaning of remote sensing: the broad interpretation, all long-range detection without contact with the target; the narrow interpretation, using modern optical and electronic detection instruments, without contact with the target, The electromagnetic wave characteristics of the target are recorded from a long distance, and the characteristics, properties and changes of the target are revealed through analysis and interpretation. ^[1]

Remote sensing is a comprehensive technology for ground observation. Its implementation requires both a complete set of technical equipment and the participation and cooperation of multiple disciplines. Therefore, implementing remote sensing is a complex systematic project. According to the definition of remote sensing, the remote sensing system is mainly composed of the following four parts:

As a comprehensive technology of ground observation, the emergence and development of remote sensing is not only an objective need for people to understand and explore the natural world, but also has characteristics unmatched by other technical means. The characteristics of remote sensing technology can be summarized in the following three aspects: 1. Wide detection range and fast data collection. Remote sensing detection can make ground observations in a wide range of areas from the air and even space in a short period of time. Value of remote sensing data. These data expand people's visual space, create extremely favorable conditions for grasping the current situation of ground things in a macro view, and also provide valuable first-hand information for macro studies of natural phenomena and laws. This advanced technical means is irreplaceable compared with traditional manual operations. 2. It can dynamically reflect changes in ground things. Remote sensing detection can periodically and repeatedly make ground observations in the same area, which helps people to discover and dynamically track changes in many things on the earth through the obtained remote sensing data. At the same time, study the changing laws of nature. The use of remote sensing is particularly important in monitoring weather conditions, natural disasters, environmental pollution and even military objectives. 3. The acquired data has comprehensive remote sensing detection. The remote sensing data obtained during the same period and covering a large area is a comprehensive display of many natural and human phenomena on the earth, and reflects the shape of various things on the earth in a macroscopic way And distribution, which truly reflects the characteristics of geological features, geomorphology, soil, vegetation, hydrology, artificial structures and other features, and comprehensively reveals the correlation between geographical things. And these data have the same current situation in time.

1. Access to a wide range of data

The altitude of the aerial photography aircraft for remote sensing is about 10km, and the satellite orbit height of land satellites is about 910km, so that a wide range of information can be obtained in time. For example, a terrestrial satellite image can cover an area of more than 30,000 km2. This kind of image showing a macroscopic scene is extremely important for the analysis of earth resources and environment. ^[1]

2. Fast access to information and short cycle

Because satellites orbit the earth, they can obtain the latest information on various natural phenomena in the area in time to update the original data or perform dynamic monitoring based on changes in old and new data. This is unmatched by artificial field measurements and aerial photogrammetry. For example, land satellites 4, 5 can cover the earth once every 16 days, and NOAA weather satellites can receive images twice a day. Meteosat acquires images of the same area every 30 minutes. ^[1]

3. Limited access to information

There are many places on the earth with extremely harsh natural conditions that are difficult for humans to reach, such as deserts, swamps, and high mountains. The use of remote sensing technology that is not limited by ground conditions, especially space remote sensing, can conveniently and timely obtain a variety of valuable data, and can detect the geographical environment at any time. ^[1]

4. There are many means to obtain information, and the amount of information is large

According to different tasks, remote sensing technology can choose different wavebands and remote sensing instruments to obtain information. For example, visible light can be used to detect objects, and ultraviolet, infrared and microwave can also be used to detect objects. With the different penetrability of objects in different wave bands, the internal information of the objects can also be obtained. For example, the deep layer of the ground, the lower layer of water, the water body under the ice, the characteristics of the ground below the desert, etc., the microwave band can also work all day. ^[1]