Advanced B-mode Flashcards
1
Q
Scanner diagram
A
2
Q
What is scan conversion?
A
Polar -> cartesian
3
Q
Three factors that affect FR?
A
depth
sector width
line density
4
Q
What are the benefits of spatial compounding?
A
Uncorrelated artefact patterns
=> less speckle, less side lobe clutter etc.
=> improved contrast resolution
5
Q
How does frequency compounding work?
A
Split beamformed RF data into three using BPFs.
Create three separate images, then take average.
Uncorrelated artefacts patterns => improved contrast res.
6
Q
How does coded excitation work?
A
Encode phase of Tx. Convolve with matched filter on Rx.
Sum results for Golay pair.
Improves SNR, and long pulse does not reduce axial res.
7
Q
In coded excitation, what does complimentary pulse in Golay pair used for?
A
Reduces range lobes.
