MICROWAVE IMAGING

ICT/2013/2014GROUP Jaspers

Microwave Imaging

CONTENTSwhat is microwave imaging

Microwave imaging techniques

Principles of microwave imaging

How it happens

Applications of microwave imaging

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Microwave Imaging

WHAT IS MICROWAVE IMAGING?

Microwave imaging is a science which has been evolved from older detecting/locating techniques in order to evaluate hidden or embedded objects in a structure or media using electromagnetic in microwave regime (i.e., ~300 MHz-300 GHz)

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Microwave Imaging

MICROWAVE IMAGING TECHNIQUESMicrowave imaging techniques are two

foldas

Quantitative imaging techniques

Qualitative imaging techniques

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Microwave Imaging

QUANTITATIVE IMAGING TECHNIQUES

Quantitative imaging techniques give the electrical (i.e., electrical and magnetic property distribution) and geometrical parameters (i.e., shape, size and location) of an imaged object by solving a nonlinear inverse problem

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Microwave Imaging

QUALITATIVE IMAGING TECHNIQUES

Qualitative microwave imaging methods calculate a qualitative profile (which is called as reflectivity function or qualitative image) to represent the hidden object.

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Microwave Imaging

PRINCIPLES OF THE MICROWAVE IMAGING A microwave imaging system has two

parts

Hardware; responsible to collect data from the sample under

testSoftware (or post-processing)

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Microwave Imaging

HOW IT HAPPENS?

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Microwave Imaging

A transmitter antenna sends EM waves toward sample under test(E.g. human body for medical imaging)

If the sample is made of only homogeneous material which extends to infinity,no EM wave will be reflected

If the sample has any anomaly,in comparison with the surrendering homogeneous medium may reflect a portion of EM wave

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Microwave Imaging

This reflection will be collected and measured by the same antenna (in monostatic case) or a different receiver antenna (in bistatic case).

When the antenna finishes scanning the entire sampling area, one can put together collected data all over the sampling area and process them together, simultaneously.

The collected data which is sometimes referred as raw data is fed into the software part to get processed.

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Microwave Imaging

APPLICATIONS OF MICROWAVE IMAGINGMicrowave imaging has been used in a

variety of applications Medical imaging Nondestructive testing and evaluation Structural health monitoring Concealed weapon detection at security

check points Through-the-wall imaging Radar

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Microwave Imaging

Nondestructive testing and evaluation

Flaw detection in spray-on foam insulation and the acreage heat tiles of the Space Shuttle.

Corrosion and precursor pitting detection in painted aluminum and steel substrates,

Disbond detection in strengthened concrete bridge members retrofitted with carbon fiber reinforced (CFRP) composite laminates

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Microwave Imaging

Structural health monitoring

Electromagnetic waves in low frequency (e.g., <10 GHz) can easily penetrate inside concrete and reach to object of interest which is usually radar

Microwave imaging also can be used to detect any embedded anomaly inside concrete

Medical imaging

Microwave imaging is a method for the detection of early stage breast cancer.

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Microwave Imaging

Concealed weapon detection at security check pointsThese security systems employ methods

derived from microwave holography techniques that utilize phase and amplitude information recorded over a two-dimensional aperture to reconstruct a focused image of the target.

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Microwave Imaging

Through-the-wall imagingThrough-the-Wall Microwave Imaging

(TWMI) radar system facilitates us to detect and localize objects behind the wall.

Through wall imaging of moving targets

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Microwave Imaging

RadarThis is the major application of microwave

band.Its unique ability is to collect data over

virtually any region at any time without regarding the weather or ambient light condition.

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Microwave Imaging 17

Thank You!

Referenced:https://nsidc.org/cryosphere/seaice/study/active_remote_sensing.htmlhttps://en.wikipedia.org/wiki/Microwave_imaging