US 12,216,234 B2
Measurement and imaging instruments and beamforming method
Chikayoshi Sumi, Saitama (JP); and Naoto Yamazaki, Kanagawa-ken (JP)
Assigned to Chikayoshi Sumi, Saitama (JP)
Filed by Chikayoshi Sumi, Saitama (JP)
Filed on Feb. 28, 2024, as Appl. No. 18/589,890.
Application 18/589,890 is a continuation of application No. 17/394,615, filed on Aug. 5, 2021, granted, now 11,965,993.
Application 17/394,615 is a continuation of application No. 15/951,459, filed on Apr. 12, 2018, granted, now 11,125,866, issued on Sep. 21, 2021.
Application 15/951,459 is a continuation in part of application No. 14/730,583, filed on Jun. 4, 2015, granted, now 10,624,612, issued on Apr. 21, 2020.
Claims priority of application No. 2017-100947 (JP), filed on May 22, 2017; application No. 2017-122554 (JP), filed on Jun. 22, 2017; application No. 2017-137185 (JP), filed on Jul. 13, 2017; application No. 2017-144588 (JP), filed on Jul. 26, 2017; application No. 2017-157256 (JP), filed on Aug. 16, 2017; application No. 2017-157590 (JP), filed on Aug. 17, 2017; application No. 2017-207592 (JP), filed on Oct. 26, 2017; application No. 2017-225982 (JP), filed on Nov. 24, 2017; application No. 2017-242013 (JP), filed on Dec. 18, 2017; and application No. 2017-245377 (JP), filed on Dec. 21, 2017.
Prior Publication US 2024/0241238 A1, Jul. 18, 2024
Int. Cl. G01S 7/52 (2006.01); A61B 6/00 (2024.01); A61B 8/00 (2006.01); G01S 15/89 (2006.01); G01S 17/90 (2020.01)
CPC G01S 7/52039 (2013.01) [A61B 6/00 (2013.01); A61B 8/00 (2013.01); G01S 7/52019 (2013.01); G01S 7/52023 (2013.01); G01S 7/52025 (2013.01); G01S 7/52033 (2013.01); G01S 7/52038 (2013.01); G01S 7/52041 (2013.01); G01S 7/52046 (2013.01); G01S 7/52047 (2013.01); G01S 15/89 (2013.01); G01S 15/8915 (2013.01); G01S 15/8997 (2013.01); G01S 17/90 (2020.01); A61B 8/4488 (2013.01)] 46 Claims
OG exemplary drawing
 
1. A measurement imaging apparatus for generating an image signal of a measurement object when at least one wave is transmitted toward said measurement object from at least one wave source located in at least one arbitrary direction, said measurement imaging apparatus comprising:
a plurality of reception aperture elements configured to receive at least one wave arriving from said measurement object and generate reception signals respectively;
a signal processing unit configured to generate said image signal in a desired coordinate system having coordinate axes in at least two directions by applying beamforming processing for at least one of transmission and reception, said beamforming processing including steering for said at least one of transmission and reception to form a steering angle expressed in terms of zero or non-zero deflection angle or elevation and azimuth angles with respect to a frontal direction of said plurality of reception aperture elements based on delay-and-summation processing regarding plural signals obtained for said plurality of reception aperture elements,
wherein said plural signals are obtained as interpolation-approximate signals at a desired time point or a desired spatial location where said beamforming processing is applied, by performing at least phase rotation to one of said reception signals, quadrature detection signals of said reception signals, IQ signals (in-phase signals and orthogonal phase signals) of said reception signals, and analytic signals of said reception signals, and said phase rotation is based on one of:
(a) multiplication by a complex exponential function having an exponential part which is a product of a single angular frequency selected at a sampling time point near said desired time point and a time difference between said desired time point and said sampling time point; and
(b) multiplication by a complex function having an exponential part which is a product of a single angular wavenumber selected at a spatial sampling location near said desired spatial location and a spatial difference between said desired spatial location and said spatial sampling location.