Microwave Tomography

Question 1

What are the general pros and cons with the microwave diagnostic technology?

Answer 1

Microwave Tomography

Advantages:

+ No Harmful Radiation

+ Relatively Cheap

+ Relatively Simple

Disadvantages:

• Low resolution due to scattering of microwaves

Question 2

What are the main challenges with Microwave Tomography?

Answer 2

Challenges with Microwave Tomography are:

• Scattering of microwave and executed approximations limit the ouput image resolution
• Inefficient reconstruction algorithms

Question 3

Short description of Chirp-Pulse Microwave CT?

Answer 3

Chirp-Pulse Microwave CT

Linear, low contrast method that attempts to mimic the Radon transform approach used in x-ray computed tomography

CP-MCT is only good in low contrast objects

Question 4

Compare advantages and disadvantages of Microwave Imaging, CT-imaging and Ultrasound.

Answer 4

Question 5

Which are the three microwave image reconstruction methods discussed during lectures?

Answer 5

Microwave Image Reconstruction Methods

1. Chirp-Pulse Microwave Computed Tomography (CP-MCT)
2. Iterative Algorithm
3. Priori Algorithm

Question 6

Which algorithm is best to use for high-resolution object? What are the differences between Iterative and Priori algorithms?

Answer 6

Both Iterative and Priori algorithm deals with high resolution objects and both are iterative algorithms, but Priori can incorporate priori object information and therefore converges faster and gives better resulting images.

Question 7

What can a priori information be useful for?

Answer 7

Different kind of a priori information can be used for

1. Regularization of the problem
2. Overcoming the non linear effects
3. Improve convergence rate

Question 8

Describe the steps of an iterative algorithm

Answer 8

Algorirthm steps:

1. Start with initial estimated image
2. Compare with the projection and get error
3. Update initial estimate
4. Go to step 1 until convergence (i,e until error is minimized)

Question 9

What is the purpose of an Iterative Reconstruction Method?

Answer 9

An Iterative Reconstruction Method

1. To overcome the problem with large and high contrast objects iterative methods are used
2. A penalty function is defined and minimized