remote sensing in digital model elevation

TAE – IISUB : Survey II

Topic : Applications of Remote sensing In Digital Model Elevation

Submiteed By:Shishir M.Meshram (A-71)Piyush R.Nimje (A-72)Akash Dehankar (A-73)Akhil Karumuri (A-74)Faizan R.Khan (A-75)

Submitted To:

Dr. B.V.Khode

Remote Sensing.Remote sensing is the acquisition of information about an

object or phenomenon without making physical contact with the object.

It is done through the Electromagnetic rays signals.Use of aerial sensor technologies to detect and classify

objects on Earth by means of propagated signals.Remote sensing makes it possible to collect data on

dangerous or inaccessible areas.Remote Sensing is broadly classified in 2 types

◦ Active Sensing.

◦ Passive Sensing.

Digital Elevation Model(DEMs)A digital elevation model (DEM) is a digital representation

of ground surface topography or terrain.Digital Elevation Model are commonly built using remote

sensing techniques.Very much used to make terrain maps.The DEMs are generally prepared

◦  random ◦ systematic.

The terrain can only be described by Point Line Area

Production

The older method includes the interpolation of contours for getting DEMs.

The electromagnetic rays are recorded and they processed

Digital elevation models may be prepared in a number of ways But two methods are common◦Two passes of a radar satellite.◦A single pass if the satellite is equipped with two

antenna.

The quality of a DEMThe quality of Digital Elevation Model

depends upon the following points and the pixels◦Terrain roughness;◦Sampling density (elevation data collection

method);◦Grid resolution or pixel size;◦Interpolation algorithm;◦Vertical resolution;◦Terrain analysis algorithm;

Processing Of Data

Following are the steps in processing◦Spatial resolution◦Spectral resolution◦Radiometric resolution◦Temporal resolution◦Radiometric correction◦Atmospheric correction

SatelliteRADARSAT

◦ RADARSAT International (RSI) was formed in 1989 by a consortium to market, process, and distribute data worldwide from Canada's RADARSAT-1 Earth-observation satellite and the data is used for remote sensing.

Magellan (spacecraft)◦ Lauched by the U.S the Satellite provides world wide data.

TerraSAR-X◦ TerraSAR-X, a radar Earth observation satellite is a joint venture

being carried out under a public-private-partnership between the German Aerospace Center (DLR) and EADS Astrium.

A typical view of Magellan (spacecraft)

Images taken by RADARSAT

TerraSAR-X

Error detection and correction

 Errors can be classified in two different categories

1. Positional errors

2. Attribute errorsBoth types of errors are introduced when DEMs are

created manually or automatically.It is necessary to consider certain criteria for their

detection and measurement

Software Used:TacitView from 2d3Socet GXP from BAE Systems,TNTmips from MicroImages,PCI Geomatica made by PCI Geomatics, the

leading remote sensing software package in Canada,

IDRISI from Clark Labs,Image Analyst from Intergraph,and RemoteView made by Overwatch Textron

Systems.

ReferencesSchowengerdt, Robert A. (2007). Remote

sensing: models and methods for image processing.

www.wikipedia.comwww.google.com/aedumenia.inPodobnikar, Tomaz (2008). "Methods for visual

quality assessment of a digital terrain model