What is Spatial Resolution or GSD in Remote Sensing?

 

🌍 What is Spatial Resolution in Remote Sensing 🛰️

• Spatial resolution or Ground Sample Distance (GSD) is a key factor in remote sensing, defining the level of detail captured in an image.
• The spatial resolution specifies the pixel size of images from Remote Sensing sensor corresponding to coverage area in the earth surface.
• It is depending on the sensor width, focal length and the altitude at which the images are captured.
• It simply refers the visual clarity of the earth images captured by the remote sensing sensor or how much detail in image is visible to the human eye to distinguish the earth feature.

Spatial Resolution in Remote Sensing Image

From the above picture 0.3-meter resolution is consider as high spatial resolution image because one pixel represents one 30 centimeter object in ground.

#RemoteSensingInsights #SpatialResolution #Geospatial #SatelliteVision #RemoteSensingTech #HighResolutionMapping #EarthObservation #GIS #DataScienceInEarthMonitoring #GSD #AerialSurvey #RemoteSensingImage #AerialImageAcqusition #DroneMapping #AerialMapping #Learnwithleo

Types of Remote Sensing

 

📡Types of Remote Sensing📷

Remote Sensing is classified based on Energy Source 

•  Active Remote Sensing
•  Passive Remote Sensing 

Remote Sensing Types

1. Active Remote Sensing

• Active sensors emit their own energy in order to scan objects and areas whereupon a sensor then detects and measures the radiation that is reflected or backscattered from the target
• RADAR, Ultrasonic and LiDAR technologies are working under Active Remote Sensing technique
• In Active Remote Sensing, the energy is generated using artificial devices

2. Passive Remote Sensing

• Incident solar energy (energy from sun) is absorbed, reflected and transmitted by the object
• The reflected solar energy was detected by the sensor is called Passive Remote Sensing
• RGB camera, multispectral camera and thermal camera-based aerial image acquisition is the best example for passive remote sensing
• It requires sunlight as source. so that the data acquisition can’t be done at night time under this technique

#RemoteSensingTypes #ActiveRemoteSensing #PassiveRemoteSensing #Radiation #LiDAR #SolarEnergy #RemoteSensingSensor #Multispectral #AerialImage #ImageAcqusition #AerialSurvey #AerialMapping

Remote Sensing Electromagnetic Spectrum

🌐 Remote Sensing Electromagnetic Spectrum🛰️

• Electromagnetic energy travels in an atmosphere as wave that are measured in wavelength and at speed measured by frequency 10⁹
• Wavelength is the mean distance between maximums or minimums of a roughly periodic pattern and it is normally measured in micrometers (um) or nanometers (nm 10-9)
• Frequency is the number of wavelengths that pass a point per unit time

Remote Sensing Electromagnet Spectrum

Based on wavelength region the remote sensing classified into 3 major types

1. Visible and Infrared Remote Sensing

2. Thermal Infrared Remote Sensing

3. Microware Remote Sensing

Table 1 Remote Sensing Electromagnetic Spectrum Table

SNo	Name	Wavelength(nm)
1	Optical Wavelength	0.30-15
2	Reflective 1. Visible 2. Near IR 3. Mid IR	0.38-0.72 0.72-1.30 1.30-3.0
3	Far IR(Thermal and Emissivity)	7.0-15

#RemoteSensingSpectrum #ElectromagneticSpectrum #ElectromagneticWaves #Wavelength #Frequency #ThermalInfraRed #Infrared #Microwave

Energy Balance in Remote Sensing

 

🛰️Energy Balance in Remote Sensing?! 🌟🤔

• When the energy falls on the object that energy is neither absorbed nor reflected or transmitted
• The reflected energy recorded by the sensor helps to identify the details about the object
• The amount of reflected energy depends upon the property of the object (physical, structural, and chemical components)

Remote Sensing Energy Balance

#RemoteSensing #Energy #EarthScience #Environment #Technology #Geospatial #Mapping #AerialPhotography #Drones #DataCollection #DroneImageProcessing #AerialMapping  #Learnwithleo

What are the Remote Sensing Components?

 

🛰️🌐Remote Sensing Components🌟🤔

Remote Sensing components are determined by sensing the reflected or emitted energy from the object also, processing, analyzing and applying that information for environmental applications

Remote Sensing Component Life-Cycle 

A - The energy source provides the electromagnetic energy source to the target. The sources may be from sun or manmade sensors

B – Radiation and Atmosphere - It is the media by which the energy is transmitted to the target

C – Energy Interacts with the target – It is depending on the target’s physical, structural, and chemical components

D – Recording Reflected Energy by Sensor - Sensor records the transmitted, emitted or absorbed energy by the target

E & F - Transmission, Reception and Data generation – The energy recorded by the sensor has been transmitted to the receiving and processing station where the data are processed as an image

G - Data Analysis – In this stage, the images are processed, analyzed and visualized to extract the information about object

H - Data Product and Applications – Finally, the outcome of analyzed images is the data product and it is used for spatial decision-making purposes

Example

1. The visible radiation from the sun transmitted via the atmosphere that is absorbed and reflected by objects in our earth

2. The Transmitted energy recorded by optical remote sensing satellite, and the recorded data where transmitted to ground station, as signals where, they are converted as image

3. The converted images are processed and analyzed than the GIS data product such as Land Use / Land Cover Map has been generated which is used for various spatial decision making

#RemoteSensing #EarthScience #Environment #Technology #RemoteSensingComponent #Radiation #GIS #Geospatial #Mapping #AerialPhotography #Drones #DataCollection #DroneImageProcessing #AerialMapping #Learnwithleo

What is Remote Sensing?

 

🛰️ What is Remote Sensing?! 🌟🤔

• Remote Sensing means acquiring information from distance. 

• It is an science and technology of obtaining information about an object without any physical contact with-it typically from satellites, aircraft, drones or from any ground-based sensor.

• These sensors can capture various forms of energy, such as visible light, infrared radiation, microwave signals, and more, to create images and datasets that can be analyzed and interpreted for various purposes. The example for Remote Sensing observations is given below

Example for Remote Sensing Observation

#RemoteSensing #EarthScience #Environment #Technology #Geospatial #Mapping #AerialPhotography #Drones #DataCollection #DroneImageProcessing #AerialMapping  #Learnwithleo #WhatisRemoteSensing