TY - GEN
T1 - Estimation of phase velocity and attenuation of visco-elastic plate with adaptive beamforming technique for cortical bone assessment
AU - Okumura, Shigeaki
AU - Taki, Hirofumi
AU - Nguyen, Vu Hieu
AU - Sato, Toru
N1 - Funding Information:
This work was supported in part by a Grant-in-Aid for Scientific Research (A) (Grant No. 25249057) and a Grant-in-Aid for JSPS Fellows (Grant No. 15J05687)
Publisher Copyright:
© 2017 IEEE.
PY - 2017/10/31
Y1 - 2017/10/31
N2 - The non-invasive cortical bone quality assessments using ultrasound axial transmission technique have attracted strong attention. The estimation of phase velocity and attenuation of absorbing plate should help the assessment. To get the high-resolution estimation, we employ an adaptive beamforming technique that uses an eigenvalue decomposition. The technique can estimate not only the phase velocities but also intensities of the multiple propagation modes separately. We situate two arrays in the whole array and compare the estimated intensities at the adjacent arrays. To remove unreliable estimates, we also situate sub-arrays with multiple sizes in the two arrays and evaluate the correspondences between the results with different sub-array sizes. The proposed method was evaluated by using numerical simulation. We used one transmitter and 28 receivers and a 5-mm-thick plate with longitudinal and shear wave velocities of 4430 m/s and 2120 m/s, respectively. The attenuations of the longitudinal and shear waves were 320 dB/MHz/m and 400 dB/MHz/m, respectively. The estimation error of the phase velocity and attenuation was 3.6 m/s and 2.4 dB/m, respectively. The proposed method accurately estimated the phase velocity and attenuation. We believe the method is suitable for bone quality assessments.
AB - The non-invasive cortical bone quality assessments using ultrasound axial transmission technique have attracted strong attention. The estimation of phase velocity and attenuation of absorbing plate should help the assessment. To get the high-resolution estimation, we employ an adaptive beamforming technique that uses an eigenvalue decomposition. The technique can estimate not only the phase velocities but also intensities of the multiple propagation modes separately. We situate two arrays in the whole array and compare the estimated intensities at the adjacent arrays. To remove unreliable estimates, we also situate sub-arrays with multiple sizes in the two arrays and evaluate the correspondences between the results with different sub-array sizes. The proposed method was evaluated by using numerical simulation. We used one transmitter and 28 receivers and a 5-mm-thick plate with longitudinal and shear wave velocities of 4430 m/s and 2120 m/s, respectively. The attenuations of the longitudinal and shear waves were 320 dB/MHz/m and 400 dB/MHz/m, respectively. The estimation error of the phase velocity and attenuation was 3.6 m/s and 2.4 dB/m, respectively. The proposed method accurately estimated the phase velocity and attenuation. We believe the method is suitable for bone quality assessments.
KW - Adaptive signal processing
KW - Axial transmission
KW - Cortical bone
KW - Guided wave
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U2 - 10.1109/ULTSYM.2017.8091594
DO - 10.1109/ULTSYM.2017.8091594
M3 - Conference contribution
AN - SCOPUS:85039413469
T3 - IEEE International Ultrasonics Symposium, IUS
BT - 2017 IEEE International Ultrasonics Symposium, IUS 2017
PB - IEEE Computer Society
T2 - 2017 IEEE International Ultrasonics Symposium, IUS 2017
Y2 - 6 September 2017 through 9 September 2017
ER -