T1-weighted 3D gradient echo LAVA fat-suppressed sequence, in the sagittal, coronal and axial planes (TR/TE range 4.4/2.1; flip angle 12°; section thickness 3.4 mm; overlap locations −1.7 mm; bandwidth 62.5 kHz; FOV 40 cm; matrix 320 × 192; number of averages 0.75; number of images 104; acquisition time 22 s).
First, functional images were aligned with the high-resolution co-planar T2-weighted image (TR = 5000 ms, TE = 31 ms, flip angle = 90 degrees, FOV = 200×200 mm, slice thickness = 3 mm, slices = 29, inter-slice gap = 1 mm, bandwidth = 1628) using 6 degrees of freedom rigid-body warping procedure.
Functional images were acquired in the AC-PC orientation using T2*-weighted echo-planar scans (TR = 2000 ms, TE = 35 ms, flip angle = 80 degrees, FOV = 192×192 mm, slice thickness = 3 mm, number of slices = 29, inter-slice gap = 1 mm, bandwidth = 3256 Hz/pixel).
Next, the co-planar volume was registered to the T1-weighted MP-RAGE (TR = 1900 ms, TE = 3.43 ms, TI = 900 ms, flip angle = 9 degrees, FOV = 256×256 mm, slice thickness = 1 mm, number of slices = 160, inter-slice gap = .5 mm, bandwidth = 180 Hz/pixel) using a six degrees of freedom rigid-body warp.
Twenty-seven whole brain T2*-weighted echo planar images per volume with BOLD contrast were obtained (TR = 3000 ms, TE = 40 ms, flip angle 90°, matrix: 64 × 64, FoV: 24 × 24 cm, slice thickness 5 mm, bandwidth 62.5 kHz).
SSFP cine images were obtained during the 20-min post-stress period (TR 2.90 ms, TE 1.19 ms, flip angle 50°, voxel size 1 × 1 × 6 mm, bandwidth 930 Hz/ pixel).
Att = 2 mm, the bandwidth corresponding to reflection loss below −10 dB (i.e., over 90% microwave absorption) is higher than 1.5 GHz.
The imaging parameters were as follows: 3D TOF: 18/2.84 (TR/TE); flip angle, 20°; section thickness, 0.77 mm; readout bandwidth, 300 Hz/pixel; rectangular field of view, 210 mm; matrix, 256 × 256; unenhanced true FISP: 6.82/3.41 (TR/TE); flip angle, 70°; section thickness, 0.7 mm; readout bandwidth, 501 Hz/pixel; rectangular field of view, 210 mm; matrix, 256 × 256.
The reflection loss (RL) was calculated from complex permittivity and permeability data and maximum RL of −37.7 dB at 10.2 GHz with a sample thickness of 2.5 mm and bandwidth of 0.53 dB.
The minimum RL of −17.18 dB has been observed for 2 wt% Cu dispersed SiC composite at 11.81 GHz with a thickness of 1.3 mm and bandwidth corresponding to −10 dB is 1.77 GHz.
Simulated results demonstrate that, with the same area of 5.5mm by 10 mm, rejection bandwidth of the proposed filter is from 4.4 GHz to 10.5 GHz for the common-mode noise (CM) while that of the traditional dumbbell-shaped DGS is from 5.3 GHz to 7.3 GHz.
