Applications to Real Measured Data - Introduction to Imaging from Scattered Fields - page 120

(g)

k -space data

×10 6

0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.4 -0.2

2.5

2

1.5

1

0.5

0 0.2 0.4

λ

(a) (b) (c)

k -space data k -space causal vsi

×10 6
2.5

×10 6

4 4

3
2
1
0
-1
-2
-3
- -4

4
3
2
1
0
-1
-2
-3
- -4

230 2.5

3
2
1
0
-1
-2
-3
- -4

220
210
200
190
180
170
160
150
140
130

2 2

1.5 1.5

1 1

0.5 0.5

0

-3 -2 -1 01234 -3 -2 -1 01234 -3 -2 -1 01234

λ λ λ

(f ) (e) (d)

Filter Minimum phase vsi

4
3
2
1
0
-1
-2
-3
-4

4
3
2
1
0
-1
-2
-3
-4
-4

4
3
2
1
0
-1
-2
-3
-4
-4

1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0

1
0.5
0
-0.5
-1
-1.5
-2
-2.5

3

2.8

2.6

2.4

2.2

2

1.8

-4 -3 -2 -1 01234 -3 -2 -1 01234 -3 -2 -1 01234

λ λ λ

Figure 9.3 Cepstral inversion steps: (a) Born reconstruction, (b) k -space data, (c) causal k -space data with reference added at origin, (d) minimum phase V 〈Ψ〉 , (e) Gaussian ilter, (f)
cepstral reconstruction, and (g) zoomed k -space data.