US 11,852,754 B2
Ultrafast ultrasound imaging with cascaded dual-polarity waves
Yang Zhang, Hong Kong (CN); Yuexin Guo, Hong Kong (CN); and Wei-Ning Lee, Hong Kong (CN)
Assigned to Versitech Limited, Hong Kong (CN)
Appl. No. 16/767,009
Filed by VERSITECH LIMITED, Hong Kong (CN)
PCT Filed Dec. 5, 2018, PCT No. PCT/CN2018/119321
§ 371(c)(1), (2) Date May 26, 2020,
PCT Pub. No. WO2019/114585, PCT Pub. Date Jun. 20, 2019.
Claims priority of provisional application 62/597,708, filed on Dec. 12, 2017.
Prior Publication US 2021/0000450 A1, Jan. 7, 2021
Int. Cl. A61B 8/14 (2006.01); G01S 7/52 (2006.01); G01S 15/89 (2006.01)
CPC G01S 7/52026 (2013.01) [A61B 8/14 (2013.01); G01S 15/8927 (2013.01); G01S 15/8959 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method implemented by an ultrasound imaging system for ultrasound imaging, the method comprising:
transmitting, by a transmitter of the ultrasound imaging system, an incident signal towards an object of interest;
receiving, by a receiver of the ultrasound imaging system, sets of reflected signals from the object of interest;
signal processing, by a processing unit of the ultrasound imaging system, the reflected signals to recover an output;
displaying, by an image display of the ultrasound imaging system, the recovered output;
wherein the incident signal is an array comprised of sets of N number of tilted cascaded waves in a temporal domain and M represents a number of sub-apertures in a spatial domain,
wherein N=2k and k is an integer,
wherein M=2q and q is an integer,
wherein the tilted cascaded waves of the incident signal have predetermined polarities, and
wherein the signal processing comprises spatiotemporal coding generating polarity coefficients of the tilted cascaded waves from each sub-aperture by matrix CNHM based on an M×M Hadamard matrix and Cascaded Dual-polarity Waves (CDW) temporal coding matrix of Cascaded Dual-polarity Waves perform synthetic-transmit-aperture (ST A) imaging, and wherein the spatiotemporal coding generates an SNR increase of 10×log10(N×M), wherein N is the number of tilted cascaded waves and where M is the number of sub-apertures,
wherein the CDW matrix is generated by
determining the number of tilted cascaded waves, N, transmitted in the incident signal;
providing a 2×2 Hadamard matrix comprising

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repeating and rearranging each element of the 2×2 Hadamard matrix in a predetermined manner to obtain a 2×N first matrix, including steps of obtaining a 2×4 CDW matrix comprising C2×4, wherein a first column is a column vector of

OG Complex Work Unit Math
a second column is a column vector of

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a third column is a column vector of

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a first column is a column vector of

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wherein · denotes scalar multiplication, then converting the C2×4 matrix to a 2×8 CDW by partitioning the C2×4 into four groups as

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where A, B, C, and D, each is 1×2 row vector, then, obtaining the first and the second columns of the 2×8 CDW matrix by multiplication of

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by the vector A, obtaining the third and the fourth columns of the 2×8 CDW matrix by multiplication of

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by the vector C, obtaining the fifth and the sixth columns of the 2×8 CDW matrix by multiplication of

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by the vector B, obtaining the seventh and the eighth columns of the 2×8 CDW matrix by multiplication of

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by the vector D to generate the 2×8 CDQ matrix comprising

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providing a 2×N second matrix by taking each element in the 2×N first matrix to form a column vector and concatenating N column vectors formed; and
providing a third 2×N matrix by element wise multiplication of the 2×N first matrix and the 2×N second matrix.