These lectures are related to Environmental sciences applications

1. October 14, 2020
Fundamentals of RS
1
Lecture 3-RS

2. Lecture # 03 Dated:14/10/2020
Course(502) Introduction
to GIS and RS
Fundamentals of Remote Sensing
Topic
Presented by
Rehana Jamal (Geometiciation, GIS Specialist & Geographer)
Visiting lecturer
studentsdatafiles@gmail.com
Faculty of Agricultural Engineering, Arid Agriculture University,
Rawalpindi
2
 What is Remote sensing
 Characteristics of Electromagnetic radiation
 Energy Sources or Illumination
 How Remote Sensing works?
 Energy interaction with the Atmosphere
 Energy Interactions wit the Earth
October 14, 2020
Fundamentals of RS
Let-3
Let-4

3. “Remote Sensing (RS) is the
science and art of acquiring
information about material
objects, area, or phenomenon,
without coming into physical
contact with the objects, area, or
phenomenon under investigation”
What is Remote sensing?
October 14, 2020
3
Fundamentals of RS
Source: https://www.google.com/

4. October 14, 2020
Fundamentals of RS
4
Source: https://www.google.com/

5. October 14, 2020
Fundamentals of RS
5
RS happens due to the radiation of Electromagnetic waves from coming the sun
C (Velocity of light)
Source of Electromagnetic waves

6. October 14, 2020
Fundamentals of RS
6

7. October 14, 2020
7
Source: https://phys.org/news/2018-04-vr-focus-nanostructure-meta-lenses.html
Visible Band of Electromagnetic waves
Fundamentals of RS

8. October 14, 2020
Fundamentals of RS
8
Characteristics of Electromagnetic radiation
Electromagnetic Energy can be modelled in two ways
i. By waves ii. By Photons (Energy bearing particles)
Electromagnetic waves consist of a combination of oscillating electrical
and magnetic fields, perpendicular to each other.
C (Velocity of light)

9. October 14, 2020
Fundamentals of RS
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Electromagnetic Spectrum
Source: https://www.google.com/

10. October 14, 2020
Fundamentals of RS
10
Source: https://www.google.com/
Electromagnetic Spectrum

11. October 14, 2020
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i. It can travel through empty space.
ii. The speed of light is constant in space.
iii. Wavelength: Distance between crests or troughs through visible light
iv. Velocity: 186,000 miles per second or 300,000 kilometers per second or
299,790,000m/s or 3*108 m/s
v. Amplitude: The amplitude of electromagnetic waves relates to its intensity or
brightness(as in the case of visible light) or the maximum extent of a vibration or
oscillation, measured from the position of equilibrium (mid point of wavelength)
vi. Frequency:
 The number of crests of the waves that pass by a point per second.
 Measured in units of hertz(Hz)
 1 hertz = 1 wave crest/second
Characteristics of Electromagnetic radiation / Crest

12. October 14, 2020
Fundamentals of RS
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/ Crest
Velocity of light, c

13. October 14, 2020
Fundamentals of RS
13 Note the trends: bluer light has shorter wavelength, higher frequency,
and more energy. Redder light has longer wavelength, lower frequency,
and less energy.
Wavelength is a reciprocal of Frequency

14. October 14, 2020
Fundamentals of RS
14
f or V = c/
Relation between the speed of light (c),
wavelength ( ), and frequency (f or V ):
Thus, there is an inverse relationship between
wavelength and frequency

15. October 14,
2020
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Thus (frequency [f or V] * wavelength[lambda]) is equal to a constant (c)
Relation between the speed of light (c), wavelength ( ),
and frequency ( ƒ or v):
Fundamentals of RS

16. October 14, 2020
Fundamentals of RS
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Measurement of Electromagnetic Energy(E/Q)
The amount of energy held by a photon of a
specific wavelength is given by
E or Q = h v
Since c = v
v/ƒ = frequency
v/ƒ = c/
h = 6.6262 x 10 -34 j/s Plank’s constant
E or Q = h x c/
c = 3 x 10 8 m/s Speed of light is constant
E or Q =
6.6262 x 10 -34
(3 x10 8)
x
(500nm x 10 – 9 m)
E or Q = (3.98 x 10 -19 j)
(500 x 10 – 9 m)
= 500nm

17. October 14, 2020
Fundamentals of RS
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Types of Energy Resources/Types of RS on the basis of Energy
(1.Passive & 2.Active)
Source: https://www.google.com/

18. October 14, 2020
Fundamentals of RS
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1. Passive Remote Sensing: Makes use of sensors that detect the
reflected or emitted electro-magnetic radiation from natural sources.
Source: https://www.google.com/

19. October 14, 2020
Fundamentals of RS
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2. Active remote Sensing: Makes use of sensors that detect reflected
responses from objects that are irradiated from artificially-generated
energy sources, such as radar.
Source: https://www.google.com/

20. October 14, 2020
Fundamentals of RS
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Source:
https://en.wikipedi
a.org/wiki/Remote
_sensing#/media/F
ile:Remote_Sensin
g_Illustration.jpg

21. October 14, 2020
Fundamentals of RS
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How Remote Sensing works?/How the Energy
is recorded by the Sensor (D)?
Source: https://www.google.com/
Elements of RS

22. October 14, 2020
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Source:http://giswin.geo.tsukuba.ac.jp/sis/tutorial/koko/remotesensing/Fundamental
RemoteSensing.pdf
Fundamentals of RS

23. October 14, 2020
Fundamentals of RS
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Source: https://www.google.com/
Recording of Energy by the Sensor in the form of Digital Number(DN values)

24. October 14, 2020
Fundamentals of RS
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 What is Remote sensing: Spatial data acquisition technique
 Characteristics of Electromagnetic radiation: wavelength,
frequency, amplitude, Energy(Q)
 Energy Sources or Illumination: Active & Passive
 Process of RS/Working of RS:
Summary

25. October 14, 2020
Fundamentals of RS
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References:
• www.google.com
• www.wikipedia.com
•https://www.nrcan.gc.ca/maps-tools-publications/satellite-imagery-air-photos/remote-
sensing-tutorials/fundamentals-remote-sensing-introduction/9363
• https://staff.aub.edu.lb/~webeco/rs%20lectures.htm
• Principles of Remote sensing
• edited by Lucas L.F. Janssen
•https://www.nrcan.gc.ca/sites/www.nrcan.gc.ca/files/earthsciences/pdf/resource/tutor/fu
ndam/pdf/fundamentals_e.pdf
•http://giswin.geo.tsukuba.ac.jp/sis/tutorial/koko/remotesensing/FundamentalRemoteSe
nsing.pdf