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Application of Image Processing and Data in Remote Sensing
Published in Ankur Dumka, Alaknanda Ashok, Parag Verma, Poonam Verma, Advanced Digital Image Processing and Its Applications in Big Data, 2020
Ankur Dumka, Alaknanda Ashok, Parag Verma, Poonam Verma
RADARSAT: It is an earth observation satellite launched by Canadian space agency in November 1995. It provides the spatial resolution of the C-band SAR imagery ranging from 8 to 100 meters per pixel, and the ground coverage repeat interval is of 24 days. It collects stereo RADAR imagery by means of pointing sensors at specified locations. The RADAR signals used by this satellite can also penetrate clouds cover making accessing areas invisible to other remote sensing systems. However, the returning RADAR signals are more affected by electrical and physical characteristics in the target than by its reflection and spectral pattern, therefore requiring special interpretation and spatial georegistration techniques.
Satellites
Published in Mohammad Razani, Commercial Space Technologies and Applications, 2018
Radarsat is Canada’s first Earth observation satellite and the world’s first operationally oriented radar satellite. With single frequency and different beam modes and positions, Radarsat is able to meet all the requirements for continuous and complete Earth monitoring and management. The Radarsat antenna operates in the C band (5.3 GHz frequency or 5.6 cm wavelength), which is able to penetrate clouds and precipitation. Radarsat transmits and receives with horizontal polarization (HH polarization). The backscattering of the incident signal is the result of changes in surface roughness and topography as well as physical properties such as moisture content and electrical properties.
Satellites
Published in Mohammad Razani, Information, Communication, and Space Technology, 2017
Radarsat is Canada’s first Earth observation satellite and the world’s first operationally oriented radar satellite. With single frequency and different beam modes and positions, Radarsat is able to meet all the requirements for continuous and complete Earth monitoring and management. The Radarsat antenna operates in the C band (5.3 GHz frequency or 5.6 cm wavelength), which is able to penetrate clouds and precipitation. Radarsat transmits and receives with horizontal polarization (HH polarization). The backscattering of the incident signal is the result of changes in surface roughness and topography as well as physical properties such as moisture content and electrical properties.
A Framework for High-Resolution Soil Moisture Extraction Using SCATSAT-1 Scatterometer Data
Published in IETE Technical Review, 2020
Deepak Murugan, Ajay Kumar Maurya, Akanksha Garg, Dharmendra Singh
Soil moisture (SM) is an important variable that has a major role in energy and water exchanges at land surface/atmosphere interface and in water resource management. It can be used for weather and climate prediction, drought indication, crop monitoring, soil erosion, flood control, etc. Therefore, it is necessary to develop a satellite-based system/algorithm for estimating the soil moisture at regional and global levels. Passive microwave remote sensing has been widely used to estimate soil moisture globally [1] and some of the passive sensors include Scanning Multichannel Microwave Radiometer (SMMR), Advanced Microwave Scanning Radiometer (AMSR-E), WindSat, and Soil Moisture and Ocean Salinity (SMOS). Soil moisture retrieval using active remote sensing has also been extensively researched. SM retrieval for regional scales using synthetic aperture radar (SAR) data, such as phased array L band synthetic aperture radar (PALSAR), PALSAR-2, RADARSAT-2 and Sentinel-1, is carried out [2–6] and for global scales scatterometer data are used, such as ASCAT, ERS 1 and QuickSCAT [7,8]. Soil Moisture Active Passive (SMAP) satellite launched with combination of scatterometer and radiometer for global soil moisture retrieval. But due to failure of the scatterometer, it currently works as a radiometer and is actively used to retrieve global soil moisture.
Earth observation and sustainable development goals
Published in Geomatics, Natural Hazards and Risk, 2020
Raj (2010) has used satellite remote sensing data for a hazard assessment of glacial lakes in the Zanskar basin, Jammu and Kashmir, India. Using multi-temporal satellite data, Bhatt et al. (2017) performed an assessment of one of the worst floods in the past 60 years in the state of Jammu and Kashmir in North India, which occurred in the first week of September 2014. The flood disaster footprints were extracted by using Indian Remote Sensing (IRS) satellite RISAT-1 and Canadian satellite Radarsat-2. The spatial and temporal dynamics of flood inundation and an evaluation of impacts were undertaken. Aggarwal et al. (2016) used multispectral satellite images of Landsat and IRS satellites and have mapped glacial lake outburst flood (GLOF) and evaluated risk assessment in the Teesta river basin in the Sikkim state of India. They have utilized normalized difference snow index and slope map of the area for risk evaluation from the GLOF in 140 lakes in Sikkim area.
Evaluation of Radarsat-2 quad-pol SAR time-series images for monitoring groundwater irrigation
Published in International Journal of Digital Earth, 2019
Amit Kumar Sharma, Laurence Hubert-Moy, Buvaneshwari Sriramulu, M. Sekhar, Laurent Ruiz, S. Bandyopadhyay, Shiv Mohan, Samuel Corgne
Radarsat-2 is an active SAR (synthetic aperture radar) microwave satellite with a payload of C-band (frequency = 5.4 GHz) (MacDonald Dettwiler and Associates Ltd. 2014). Nine Radarsat-2 satellite quad pol (HH, HV, VH, VV) images at fine-quad (FQ6) mode were acquired for the period from June 2013 to December 2013 (Table 1). The quad pol images consist of four polarization combinations (quad pol) includes horizontal transmission & horizontal receiving (HH pol), horizontal transmission & vertical receiving (HV pol), vertical transmission & vertical receiving (VV pol) and vertical transmission & horizontal receiving (VH pol). The low incidence angle (∼25°) with 5.3 GHz frequency antenna (C-band SAR) is one of the ideal conditions to estimate surface soil moisture (Zribi et al. 2014; Tomer et al. 2015). Low incidence angle has the least attenuation with the crop canopy, and the backscattering coefficient is mainly representing the surface soil humidity (Ulaby 1975; Srivastava et al. 2009). The ground and azimuth resolutions for all acquired images were respectively 10.9 and 4.7 m. More characteristics of the satellite images were presented in Table 1.