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Microwave Remote Sensing

Chris Allen (callen@eecs.ku.edu)

Course website URL people.eecs.ku.edu/~callen/823/EECS823.htm

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OutlineSyllabus

Instructor information, course description, prerequisites

Textbook, reference books, grading, course outline

Preliminary schedule

Introductions

What to expect

First assignment

Microwave remote sensing backgroundMicrowave remote sensing compared to optical remote sensing

Overview of radar

Microwave scattering properties

Radiometry principles and example

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SyllabusProf. Chris Allen

Ph.D. in Electrical Engineering from KU 1984

10 years industry experience

Sandia National Labs, Albuquerque, NM

AlliedSignal, Kansas City Plant, Kansas City, MO

Phone: 785-864-8801

Email: callen@eecs.ku.edu

Office: 3024 Eaton Hall

Office hours: Tuesdays and Thursdays10:00 to 10:45 am

Course descriptionDescription and analysis of basic microwave remote sensing systems including radars and radiometers as well as the scattering and emission properties of natural targets. Topics covered include plane wave propagation, antennas, radiometers, atmospheric effects, radars, calibrated systems, and remote sensing applications.

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SyllabusPrerequisites

Introductory course on electromagnetics (e.g., EECS 420 or 720)

Introductory course on RF transmission systems (e.g., EECS 622)

TextbookMicrowave Radar and Radiometric Remote Sensing

by F.T. Ulaby, D.G. Long

University of Michigan Press, 2013,ISBN 04721193541116 pages

This is a new textbook that containswhat was previously availablein the Volume I of the Microwave Remote Sensing series.

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SyllabusReference books

Microwave Remote Sensing: Active and Passive, Volume I: Microwave remote sensing fundamentals and radiometry

by F. Ulaby, R. Moore, A. Fung

Artech House, 1981, ISBN 0890061904

Unfortunately this textbook is out of print and is only available in the used book market.

Unfortunately this textbook is out of print and is only available in the used book market.Nice-quality, affordable copies were available through the KU bookstore but no longer.

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SyllabusReference books

Microwave Remote Sensing, Vol. IIby F. Ulaby, R. Moore, A. Fung Artech House, 1986, ISBN 0890061920

Microwave Remote Sensing, Vol. IIIby F. Ulaby, R. Moore, A. Fung Artech House, 1986, ISBN 0890061920

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Grades and course policiesThe following factors will be used to arrive at the final course grade:

Homework, quizzes, and class participation 40 %Research project 20 %

Final exam 40 %

Grades will be assigned to the following scale:A 90 - 100 %B 80 - 89 %C 70 - 79 %D 60 - 69 %F < 60 %

These are guaranteed maximum scales and may be revised downward at the instructor's discretion.

Read the policies regarding homework, exams, ethics, and plagiarism.

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Preliminary scheduleCourse Outline (subject to change)

Introductory material 1 week(overview, expectations, review of complex math)

Plane wave propagation, reflection, refraction, and attenuation 1 week(conductive media, layered media, Riccati equation)

Antenna systems in microwave remote sensing 2 weeks(antenna concepts, arrays)

Passive microwave remote sensing and radiometry 2 weeks(brightness temperature and emissivity)

Microwave interaction with the atmosphere 2 weeks(physical properties, precipitation effects)

Radiometer systems 1 week(system noise, Dicke radiometer)

Radar systems 2 weeks(range equation, Doppler effects, fading)

Calibrated systems and scattering measurements 1 week(internal/external calibration, measurement precision)

Scattering and emission from natural targets 2 weeks(surface scatter, volume scatter, the sea, ice, snow, vegetation)

Microwave remote sensing applications (guest lecturers) 1 week(sea ice, oceans, vegetation, etc.)

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Preliminary scheduleFall 2014 Class Meeting Schedule

August: 26, 28September: 2, 4, 9, 11, 16, 18, 23, 25, 30October: 2, 7, 9, (14th is Fall Break), 16, 21, 23, 28, 30November: 4, 6, 11, 13, 18, 20, 25, (27th is Thanksgiving)December: 2, 4, 9, 11

Final exam scheduled forMonday, December 15

10:30 to 1:00 p.m.

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Introductions

Name

Major

Specialty

What you hope to get from of this experience(Not asking what grade you are aiming for )

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What to expectCourse is being webcast, therefore …

Most presentation material will be in PowerPoint format Presentations will be recorded and archived (for duration of semester)

Student interaction is encouragedRemote students must activate microphone before speaking

Please disable microphone when finished

Homework assignments will be posted on websiteElectronic homework submission logistics to be worked out

We may have guest lecturers later in the semester

To break the monotony, we’ll try to take a couple of 2-minute breaks during each session (roughly every 15 to 20 min)

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Course coverage areas

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Course coverage areas

Course will focus on

• electromagnetic propagation & scattering

• antennas

• atmospheric effects

• radiometry and radiometers

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Your first assignmentSend me an email (from the account you check most often)

To: callen@eecs.ku.edu

Subject line: Your name – 823

Tell me a little about yourself

Attach your ARTS form (or equivalent)

ARTS: Academic Requirements Tracking System

Its basically an unofficial academic record

I use this to get a sense of what academic experiences you’ve had

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Microwave remote sensing backgroundOptical remote sensing has been around a long time• Uses the visible part of the electromagnetic spectrum• Instrumentation includes the human eye, cameras, telescopes• Has problems with clouds, rain, fog, snow, smoke, smog, etc.• Cannot penetrate soil, vegetation, snowpack, ice• Relies on ambient light sources (e.g., sunlight)

Microwave remote sensing is less than 100 years old• Uses the microwave and RF parts of the spectrum• Instrumentation includes radars and radiometers• Is largely immune to clouds, precipitation, smoke, etc.• Penetrates sand, soil, rock, vegetation, dry snow, ice, etc.• Does not rely on sunlight – radar provides its own illumination,

radiometers use the target’s thermal emission

Data from microwave sensors complement data from optical sensors

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Microwave remote sensing backgroundWhereas shorter wavelengths (e.g., optical and infrared) provide information on the upper layers of vegetation, the longer wavelengths of microwave and RF signals penetrate deeper into the canopy and substructure providing additional information.

Visible wavelengths400 to 700 nm

Infrared wavelengths700 nm to 1 mm

Microwave wavelengths1 mm to 30 cm

Radio wavelengths> 30 cm

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Microwave remote sensing backgroundA brief overview of radar

Radar – radio detection and ranging

Developed in the early 1900s (pre-World War II)• 1904 Europeans demonstrated use for detecting ships in fog• 1922 U.S. Navy Research Laboratory (NRL) detected wooden ship on Potomac

River• 1930 NRL engineers detected an aircraft with simple radar system

World War II accelerated radar’s development• Radar had a significant impact militarily• Called “The Invention That Changed The World” in two books by Robert

Buderi

Radar’s has deep military roots• It continues to be important militarily• Growing number of civil applications • Objects often called ‘targets’ even civil applications

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Microwave remote sensing backgroundA brief overview of radar

Uses electromagnetic (EM) wavesFrequencies in the MHz, GHz, THz

Shares spectrum with FM, TV, GPS, cell phones, wireless technologies, satellite communications

Governed by Maxwell’s equationsSignals propagate at the speed of lightAntennas or optics used to launch/receive waves

Related technologies use acoustic wavesUltrasound, seismics, sonar

Microphones, accelerometers, hydrophones used as transducers

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Microwave remote sensing backgroundA brief overview of radar

Active sensorProvides its own illumination

Operates in day and nightLargely immune to smoke, haze, fog, rain, snow, …

Involves both a transmitter and a receiverRelated technologies are purely passive

Radio astronomy, radiometers

ConfigurationsMonostatic

transmitter and receiver co-locatedBistatic

transmitter and receiver separatedMultistatic

multiple transmitters and/or receiversPassive

exploits non-cooperative illuminator

Radar image of Venus

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Microwave remote sensing backgroundA brief overview of radar

Various classes of operationPulsed vs. continuous wave (CW)Coherent vs. incoherent

Measurement capabilitiesDetection, RangingPosition (range and direction), Radial velocity (Doppler)Target characteristics (radar cross section – RCS)Mapping, Change detection

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Microwave remote sensing backgroundMicrowave scattering properties reveal target characteristics

Backscattering from precipitation depends strongly on particle diameter enabling a mapping of precipitation rates using radar data.

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Microwave remote sensing backgroundRadiometry principles

Materials above 0 K emit electromagnetic radiation that follows a well-defined pattern. This radiation can be measured at a variety of frequencies and polarizations. Analysis of the measured emission characteristics reveal properties about the scene.

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Microwave remote sensing background

Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) instrument was launched aboard NASA's Earth Observing System (EOS) Aqua Satellite on 4 May 2002. The AMSR-E is a twelve-channel, six-frequency, conically-scanning, passive-microwave radiometer system. It measures horizontally and vertically polarized microwave radiation (brightness temperatures) ranging from 6.9 GHz to 89.0 GHz. Spatial resolution of the individual measurements varies from 5.4 km at 89 GHz to 56 km at 6.9 GHz.