What are the key differences between optical and radar satellite imagery?

Optical Satellite Imagery 1. Optical satellites capture spectral bands on the visible spectrum 2. Satellites with optical sensors generate images of the Earth over relatively large areas and are useful in the production of vegetation maps or to estimate specific vegetation parameters 3. The sensors function in the optical part of wavelength spectrum, visible, near infrared and short-wave infrared wavelengths Radar Satellite Imagery 1. SAR (Synthetic Aperture Radar) is a type of satellite imagery using radar waves to map the Earth's surface 2. The radar transmits electromagnetic waves, they reach the surface and backscatter back to the sensor 3. Geospatial Intelligence + very high-resolution multispectral optical and radar satellite imagery

Radio cartography is a truly stable method of observation, but do not forget that resolution decreases in proportion to frequency. To achieve the same resolution, a larger aperture must be used in the Radar technology. Also, the accuracy of distance measurement differs in favor of optical location. At the same time, Radar can scan a larger area faster. Summary: to compile high-precision maps, it is most advisable to use Lidar technology, and for quickly assessing large changes (for example, a forest fire that has started with a lot of smoke), Radar technology is better suited

The coherency of sar is the main privilege of it. It can provide important data about different materials by the different polarity of reflection for each one. Although the cost of sar is usually more than optical equivalent but usually there is no device with the same information SAR can offer. The night vision capability is the other privilege of radar over optical. Plorometric SAR radar also can give us usefull information about the clouds, rain dust and other semi transparent things through radar sensor and earth

Optical and radar satellite imagery are two different types of remote sensing technologies used to capture images of the Earth's surface from space. The main differences between them are: Optical Satellite Imagery: 1. Uses visible and near-infrared light to capture images. 2. Provides high-resolution images with good spatial detail. Radar Satellite Imagery: 1. Uses microwave radiation to capture images. 2. Provides images independent of lighting conditions (day/night) and weather (clouds, haze) optical imagery is better for: - High-resolution mapping - Land cover classification Radar imagery is better for: - Detecting movement (e.g., land subsidence) - Imaging through clouds and vegetation

There are exceptions to this, such as chainlink fence around compounds. This is highlighted perfectly by SAR due to its multiple reflective sides. Often hidden in treelines it can be difficult to observe in Elelctro Optical.

Yes, resolution increases with frequency. However, it is possible to proportionally increase the aperture of the sounding antenna, and even obtain superior resolution. Which, in combination with multi-channel phase distribution (electronic scanning), allows you to recreate fairly accurate images. Low frequency technologies are generally still cheaper and more widespread. This can compensate for the larger sizes.

In fact, radio waves are also sensitive to weather conditions. There are three regions of dependence of the EPR of an object on the ratio of its size to the wavelength: Rayleigh, resonant and quasi-optical. Clouds reflect and attenuate optical waves to a greater extent and radio waves to a lesser extent. However, reflection and attenuation are also a problem in the radio range. Therefore, for example, in atmospheric radio communications, antennas with circular polarization are used. In addition, in the centimeter wavelength range there are several frequency points that coincide with absorption resonances in the atmosphere, which sometimes leads to temporary loss of the radio channel.

I must insist that Phase sensitivity and phase control of rf signal is the most advantageous feature the sar has against optical method rely on amplitude or intensity of reflected wave because the optical sensor generally are receiver and have any control on transmitted wave by sun or ... Radars have controlled engineered signal that may result to some processing gain that can help reduce noise and make clearer image by offline post processing techniques