Remote sensing is the acquisition of information about an object or phenomenon, without making physical contact with the object. It primarily concerned with deriving information about the earth’s surface using an elevated platform. History of RS is not so old. It started from manual aerial photo capturing and interpretation and now running with modern satellite image capturing. A Remote sensing system comprises all the available components (both hard and soft wares), the online server, their interactions and interrelations in doing a particular job like image processing from satellite data. RSS comprises Platforms, Sensor, Computer system, Server, Institutional setups, Energy source and finally Image interpretation. Energy interactions with the atmosphere dictate the spectral regions through which only we can do the remote sensing which are known as spectral windows. The total incident energy will interact with earth’s surface materials in three ways. These are: Absorption, Transmission, and Reflection. Radiometric and Geometric characteristics of remotely sensed images comprise Radiant energy, flux, intensity, Irradiance, emittance, Radiance, Radiometric resolution, Film exposure of sensor, Instantaneous Field Of View and Extraneous Geometric effect. Locations and other characteristics of natural features and human activities on, above and beneath the earth’s surface are recorded as information for RS. The raster (or grid-cell) data model has developed from aerial and satellite-imaging technology, which represents geographical objects as grid-cell structures known as pixels. The location of geographic objects or conditions is defined by the row and column position of the cells they occupy. Information available on remotely sensed images may have three modes or dimensions, i.e. spatial, temporal, or thematic. After image capturing and storing, images are manipulated and interpreted. The process of image processing are consists of Georeferencing, Classification and analysis. A remotely sensed data comprises following spectral characteristics like Bandwidth, Band placement, Number of bands etc.
Table of Contents
1. Definition of Remote Sensing (RS)
2. Brief history of RS
3. RS system
4. Interactions of EME with earth surface
5. Platforms and Sensors used in RS
Platforms
Sensors
6. Radiometric and Geometric characteristics of remotely sensed images
Radiometric characteristics
Geometric Characteristics
7. Information available on remotely sensed images
8. Processing of remotely sensed images
Georeferencing
Classification
Analysis
9. Spectral characteristics of remotely sensed data (Landsat TM)
Objectives and Research Themes
The report aims to provide a foundational overview of remote sensing principles, covering the historical development, technical systems, and the interaction of electromagnetic energy with the Earth's surface to facilitate data interpretation and analysis.
- Fundamental definitions and the historical evolution of remote sensing technology.
- Components of a remote sensing system and the interaction of electromagnetic energy with the Earth's surface.
- Classification of platforms and sensors utilized for data acquisition.
- Radiometric and geometric characteristics relevant to image analysis.
- Methodological approaches to processing remotely sensed images, including georeferencing and classification.
Excerpt from the Book
4. Interactions of EME with earth surface
Electro-magnetic energy (EME) interactions with atmosphere and with the earth surface play a vital role in remote sensing. Energy interactions with the atmosphere dictate the spectral regions through which only we can do the remote sensing which are known as Spectral windows (the spectral regions where atmosphere is more or less transparent).
The total incident energy will interact with earth’s surface materials in three ways. These are: Absorption, Transmission, and Reflection. Absorption (A) occurs when radiation (energy) is absorbed into the target while transmission (T) occurs when radiation passes through a target.
Reflection (R) occurs when radiation "bounces" off the target and is redirected.
Summary of Chapters
1. Definition of Remote Sensing (RS): Defines remote sensing as the acquisition of information about an object without physical contact via elevated sensors.
2. Brief history of RS: Outlines the chronological progression of remote sensing from early ballooning and photography to the era of satellites.
3. RS system: Describes the hardware and software components essential for capturing and processing satellite imagery.
4. Interactions of EME with earth surface: Explains how electromagnetic energy behaves through the atmosphere and interacts with surface materials via absorption, transmission, and reflection.
5. Platforms and Sensors used in RS: Details the various vehicles for sensors, such as aircraft and spacecraft, and categorizes sensors by their technical specifications.
6. Radiometric and Geometric characteristics of remotely sensed images: Discusses the physical units of radiant energy and the geometric challenges involved in digital image acquisition.
7. Information available on remotely sensed images: Examines the spatial, temporal, and thematic dimensions of data stored in raster or grid-cell models.
8. Processing of remotely sensed images: Covers the necessity of computer processing for repeatable interpretation, including georeferencing, classification, and spatial analysis.
9. Spectral characteristics of remotely sensed data (Landsat TM): Provides a technical breakdown of the Landsat Thematic Mapper bands and their specific applications in Earth observation.
Keywords
Remote Sensing, Electromagnetic Energy, Satellite Imagery, Georeferencing, Image Classification, Spectral Windows, Sensors, Platforms, Radiometry, Spatial Resolution, Landsat TM, Data Acquisition, Raster Model, Spectral Bands, Earth Observation
Frequently Asked Questions
What is the core focus of this report?
The report focuses on the fundamental concepts of remote sensing, including the physics of electromagnetic interaction, system architecture, and the methodologies used to process and interpret captured satellite imagery.
What are the primary thematic areas covered?
The main themes include the history of remote sensing, the technical components of RS systems, physical principles of energy interaction, sensor platforms, image characteristics, and data processing techniques.
What is the primary objective of this work?
The objective is to establish a comprehensive overview of remote sensing as a scientific tool for gathering Earth surface data without direct physical contact.
Which scientific methods are discussed in this context?
The text discusses methodologies such as image classification, georeferencing of map coordinates, spatial analysis, and spectral band identification for various environmental assessments.
What is covered in the main body of the document?
The main body covers the transition from traditional photography to modern satellite remote sensing, the specific behavior of EME on the Earth's surface, and the technical parameters of sensors used on satellites like Landsat.
How would you characterize this work using keywords?
This work is characterized by terms such as Remote Sensing, Spectral characteristics, Georeferencing, Radiometric resolution, and Earth observation systems.
How does the atmosphere influence remote sensing capabilities?
The atmosphere dictates specific spectral regions known as "spectral windows," where the atmosphere is transparent enough to allow for effective remote sensing observation.
What is the significance of the Landsat TM sensor bands?
The Landsat TM bands are specifically designed for different analytical purposes, such as water penetration, vegetation discrimination, and hydrothermal mapping, based on their unique spectral range and resolution.
What is the difference between supervised and unsupervised classification?
The text introduces these as the two types of image classification used to organize pixels into discrete, meaningful categories for map creation.
Why is georeferencing necessary for image data?
Georeferencing is essential to align image data with a proper coordinate system, enabling the transformation, scaling, and spatial positioning of the captured imagery relative to the Earth's surface.
- Quote paper
- Md. Siddiqur Rahman (Author), 2011, Introduction to Remote Sensing, Munich, GRIN Verlag, https://www.hausarbeiten.de/document/194960
