Lrm 111 assignment 3 (case study-3) 13.12.2016

1. SOKOINE UNIVERSITY OF AGRICULTURE
COLLEGE OF AGRICULTURE
DEPARTMENT OF ENGINEERING SCIENCES AND TECHNOLOGY
REMOTE SENSING AND GIS LABORATORY
Course LRM 111: Introduction to Remote Sensing
Assignment-3 (Case Study-3)
1st
SEMESTER B.Sc. Irrigation and Water Resources Engineering (B.Sc. IWRE)
Instructor(s): Prof. D.N. Kimaro
Dr. Proches Hieronimo
Date: 13 December 2016
Remote sensing is the science and art of obtaining information about an object, area, or phenomenon through
the analysis of data acquired by a device that is not in contact with the object, area, or phenomenon under
investigation. Remote sensing which measure energy that is naturally available are called passive sensors.
Passive sensors can only be used to detect energy when the naturally occurring energy is available. Active
sensors, on the other hand, provide their own energy source for illumination.
The purpose of this assignment is to study and write notes on Active remote sensing.
For each practical group write notes on the tasks given in the Table below:
Practical Group
No
Task
1 i. What advantages do sensors carried on board satellites have over those
carried on aircraft? Are there any disadvantages that you can think of?
ii. As a satellite in a near-polar sun-synchronous orbit revolves around the
Earth, the satellite crosses the equator at approximately the same local sun
time every day. Because of the orbital velocity, all other points on the globe
are passed either slightly before or after this time. For a sensor in the visible
portion of the spectrum, what would be the advantages and disadvantages of
crossing times (local sun time) (a) in the early morning, (b) around noon, and
(c) in the mid afternoon?
iii. If you wanted to map the deciduous and the coniferous trees in a forest using
remote sensing data, what would be the best way to go about this and why?
Use the reflectance curves illustrating the spectral response patterns of these
two categories to help explain your answer
iv. What would be the advantage of displaying various wavelength ranges, or
channels, in combination as colour images as opposed to examining each of
the images individually?
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2. 2 i. What is RADAR
ii. Principles of imaging radar
iii. What does a radar system measure?
iv. Geometric properties of radar
v. What is Synthetic Aperture Radar
vi. Application of radar
vii. What are the limitations of radar images in terms of visual interpretation
3 The difference between active and passive remote sensing systems in terms of (a).
Energy sources (b). Regions of spectrum in which they operate (c). Wavelength (d).
Reliance on solar irradiance (c). Providing examples of each system
4 i. The similarities and differences between RADAR and LIDAR technologies
ii. What is Laser scanning
iii. The application of LIDAR technology in Geomorphology and Forestry
iv. The application of LIDAR technology in Agriculture and Geology
5 Write notes on the application of Remote sensing in support of groundwater studies
Prepare a Group assignment/Case Study report. Submit your Group report (hard and soft copy) by 16 January
2016 before 12:30 pm. Submit your soft copy by e-mail.
Note that the all group reports should be shared among all students just after the group report is submitted.
Expect questions in the semester examination from this assignment.
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