Coherent synthesis of ultrasound images, and related systems, methods, and apparatus.

Abstract

The ultrasound imaging system includes an acoustic element configured to transmit ultrasonic energy and receive associated echoes. The system further includes a processor circuit in communication with the acoustic element. The processor circuit is configured to receive data corresponding to a set of subframes based on the echoes. The set of subframes includes first and second subframes. The processor circuit is configured to coherently combine data corresponding to a first portion of the first subframe and data corresponding to a first portion of the second subframe, both of which include phase information. The processor circuit is configured to generate an image based on the coherent combination of the first portion of the first subframe and the first portion of the second subframe and output the generated image to a display in communication with the processor circuit.

Description

Technical Field

[0001] The subject matter described herein relates to a system for medical imaging. In particular, the present disclosure describes aspects related to the generation of ultrasonic images based on the coherent combination of a set of sub-frames associated with an ultrasonic image.

Background Art

[0002] An ultrasonic imaging system includes a probe that houses a transducer array operable to transmit ultrasonic energy and receive echoes related to the transmitted energy. In some cases, a console device (e.g., a host system) of the ultrasonic imaging system controls the transmission and reception of such ultrasonic energy at the probe to generate an ultrasonic image. For example, the console device addresses (e.g., controls) a set of acoustic elements within the transducer array to transmit ultrasonic energy and receive related echoes. In particular, the console device interfaces with the probe via a set of data channels and uses the data channels to control the operation of the set of acoustic elements. In some cases, an active aperture associated with the transmission and / or reception of ultrasonic energy is defined by the number and position of acoustic elements addressed (e.g., utilized in the transducer array) by the console device for the generation of image data. As the number of acoustic elements used to transmit ultrasonic energy increases, as a result, the size of the active aperture also increases, and the resolution of the resulting ultrasonic image also increases. However, in some cases, the number of data channels in an ultrasonic system is fixed, so the number of acoustic elements that can be addressed, and thus the size of the active aperture, is limited. Additionally, or alternatively, modifications to an ultrasonic system to accommodate additional data channels are costly in terms of time and / or resources. Thus, when the number of acoustic elements within the probe exceeds the number of elements that can be addressed by the console device, an ultrasonic image will be generated using a subset of the total number of acoustic elements within the probe. [Overview of the Initiative]

[0003] Disclosed are systems, methods, and apparatus for generating ultrasound images based on the coherent coupling of at least a portion of a set of subframes associated with an image. For example, an ultrasound imaging system includes a transducer array having several acoustic elements. The ultrasound imaging system is configured to acquire ultrasound imaging data of an object (e.g., an anatomical object) using different subsets of acoustic elements (e.g., sub-apers) and / or different beam steering angles. The acquired ultrasound imaging data, when coupled, correspond to a set of subframes that produce an image of the object. In particular, the ultrasound system is configured to deal with a subset of acoustic elements and / or select a beam steering angle, and then reconstruct an effective aperture exceeding the size of the sub-apers. That is, for example, the ultrasound system is configured to deal with a subset of acoustic elements and / or select a beam steering angle such that the set of subframes are coupled to produce an image corresponding to the image (e.g., acquired) generated by the effective aperture. Furthermore, the ultrasound imaging system is configured to coherently combine (e.g., sum) at least a portion of the set of subframes (for example, with the data corresponding to the set of subframes containing phase information), thereby improving the resolution and / or penetration of the image compared to images produced by alternative techniques. In some cases, the ultrasound imaging system is configured to sum the data corresponding to the set of subframes based on incoherent and coherent data combination. For example, the ultrasound imaging system weights (e.g., masks) incoherently combined and coherent combined subframes to produce an ultrasound image having a mixture of incoherent and coherent combined features. In particular, incoherent combination of data corresponding to a set of subframes reduces speckle in the ultrasound image, coherent combination of data corresponding to a set of subframes improves the depth and penetration of the ultrasound image, and combination of incoherently combined and coherent combined data produces an ultrasound image having both reduced speckle and improved resolution and penetration.

[0004] In an exemplary embodiment, the ultrasonic imaging system includes an array of acoustic elements configured to transmit ultrasonic energy and receive echoes associated with the ultrasonic energy, and a processor circuit that communicates with the array of acoustic elements. The processor circuit is configured to receive data corresponding to a set of subframes based on the received echoes. The set of subframes includes a first subframe and a second subframe. The processor circuit is configured to coherently combine data corresponding to a first portion of the first subframe and data corresponding to a first portion of the second subframe. The data corresponding to the first portion of the first subframe and data corresponding to a first portion of the second subframe include phase information. The processor circuit is configured to generate an image based on the coherent combination of the first portion of the first subframe and the first portion of the second subframe, and to output the generated image to a display that communicates with the processor circuit.

[0005] In some embodiments, the ultrasonic energy includes a first ultrasonic energy and a second ultrasonic energy, and to transmit the ultrasonic energy, the array of acoustic elements is configured to transmit the first ultrasonic energy using a first subset of the array of acoustic elements and to transmit the second ultrasonic energy using a second subset of the array of acoustic elements. In some embodiments, a first subframe corresponds to a received echo associated with the first ultrasonic energy, and a second subframe corresponds to a received echo associated with the second ultrasonic energy. In some embodiments, to receive echoes associated with ultrasonic energy, the array of acoustic elements is configured to receive echoes associated with the first ultrasonic energy using a first subset of the array of acoustic elements and to receive echoes associated with the second ultrasonic energy using a second subset of the array of acoustic elements.

[0006] In some embodiments, the processor circuit is configured to generate an image based on envelope detection of coherent coupling. In some embodiments, the processor circuit is configured to generate an image based on log compression of coherent coupling. In some embodiments, the processor circuit is configured to perform a scan transform on data corresponding to a set of subframes. The processor circuit is further configured to coherently combine data corresponding to a first part of a first subframe and data corresponding to a first part of a second subframe based on the scan transform. In some embodiments, the processor circuit is configured to incoherently combine data corresponding to a second part of a first subframe and data corresponding to a second part of a second subframe, and to generate an image based on the incoherent combination of a second part of a first subframe and a second part of a second subframe.

[0007] In some embodiments, the processor circuit is configured to generate an image based on generating a first image based on a coherent coupling between a first portion of a first subframe and a first portion of a second subframe, generating a second image based on an incoherent coupling between a first portion of a first subframe and a first portion of a second subframe, and further combining the first image and the second image. In some embodiments, the processor circuit is configured to combine the first image and the second image based on the spatial frequency of the first portion of the first subframe. In some embodiments, the processor circuit is configured to combine the first image and the second image based on the location of the first portion of the first subframe within the first subframe.

[0008] In some embodiments, the processor circuit is configured to align a first portion of a first subframe with a first portion of a second subframe. The processor circuit is further configured to coherently combine data corresponding to the first portion of the first subframe with data corresponding to the first portion of the second subframe based on the alignment. In some embodiments, the processor circuit is configured to align a first portion of a first subframe with a first portion of a second subframe based on identifying the difference between data corresponding to the first portion of the first subframe and data corresponding to the first portion of a third subframe of the set of subframes, and adjusting the data corresponding to the first portion of the first subframe based on the identified difference. In some embodiments, the processor circuit includes a graphics processing unit (GPU).

[0009] In an exemplary embodiment, the method includes controlling an array of acoustic elements communicating with a processor circuit to transmit ultrasonic energy and receive echoes associated with the ultrasonic energy, and receiving data corresponding to a set of subframes based on the received echoes, the processor circuit including a first subframe and a second subframe. The method further includes coherently coupling data corresponding to a first portion of the first subframe and data corresponding to a first portion of the second subframe by the processor circuit. The data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe include phase information. The method further includes generating an image based on the coherent coupling of the first portion of the first subframe and the first portion of the second subframe by the processor circuit, and outputting the generated image to a display communicating with the processor circuit.

[0010] Additional aspects, features, and advantages of this disclosure will become apparent from the following detailed description.

[0011] Exemplary embodiments of this disclosure will be described with reference to the accompanying drawings. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram of an ultrasonic imaging system according to an aspect of the present disclosure. [Figure 2] This is a schematic diagram of a processor circuit according to an aspect of the present disclosure. [Figure 3] This figure shows an ultrasound image according to an aspect of the present disclosure. [Figure 4] This is a schematic diagram of the combination of a set of sub-openings for forming an effective opening, according to an aspect of the present disclosure. [Figure 5a-5b] This is a schematic diagram of ultrasonic imaging using a secondary aperture according to an aspect of the present disclosure. [Figure 6] This is a block diagram of a signal path for generating an ultrasound image using incoherent coupling of a set of subframes, according to an aspect of the present disclosure. [Figure 7] This figure shows an ultrasound image according to an aspect of the present disclosure. [Figure 8] This is a flowchart of a method for coherently combining data corresponding to a set of subframes for generating an ultrasound image, according to an aspect of the present disclosure. [Figure 9] This is a block diagram of a signal path for generating an ultrasound image using coherent coupling of a set of subframes, according to an aspect of the present disclosure. [Figure 10] This figure shows an ultrasound image according to an aspect of the present disclosure. [Figure 11] This is a block diagram of a signal path for generating ultrasonic image data based on coherent coupling and incoherent coupling of sets of subframes, according to an aspect of the present disclosure. [Figure 12] This is a block diagram of a signal path for generating ultrasonic image data based on coherent coupling of a first portion of a set of subframes and incoherent coupling of a second portion of a set of subframes, according to an aspect of the present disclosure. [Figure 13] This figure shows an ultrasound image according to an aspect of the present disclosure. [Modes for carrying out the invention]

[0013] For the purpose of facilitating understanding of the principles of this disclosure, the embodiments will be described using specific language and references to the embodiments shown in the drawings below. Nevertheless, it will be understood that the scope of this disclosure is not intended to be limited. Any modifications and further alterations to the apparatus, systems, and methods described, as well as any further applications of the principles of this disclosure, are included in this disclosure entirely as conscientiously conceived by peers relating to this disclosure. In particular, features, components, and / or steps described in relation to one embodiment are entirely conscientiously intended to be combined with features, components, and / or steps described in relation to other embodiments of this disclosure. However, for the sake of brevity, numerous repetitions of these combinations will not be described separately.

[0014] Figure 1 is a schematic diagram of an ultrasound imaging system 100 according to an aspect of the present disclosure. The system 100 is used to scan an area or volume of a patient's body. The system 100 includes an ultrasound imaging probe 110 that communicates with a host 130 via a communication interface or link 120. The probe 110 includes a transducer array 112, a beamformer 114, a processor 116, and a communication interface 118. The host 130 includes a display 132, a processor circuit 134, a communication interface 136, and a memory 138 for storing patient information. The host 130, and / or the processor 134 of the host 130, additionally communicate with a memory 140.

[0015] In some embodiments, the probe 110 is an external ultrasound imaging device including a housing 111 configured for user-held operation. The transducer array 112 can be configured to acquire ultrasound data while the user grasps the housing 111 of the probe 110 so that it is positioned adjacent to or in contact with the patient's skin. The probe 110 is configured to acquire ultrasound data of anatomical tissue inside the patient's body while being located outside the patient's body. In some embodiments, the probe 110 can be a patch-based external ultrasound probe.

[0016] In other embodiments, the probe 110 may be an internal ultrasound imaging device and comprises a housing 111 configured to be positioned within a cavity or body cavity of the patient's body, including the patient's coronary vascular structure, peripheral vascular structure, esophagus, cardiac chambers, or other body cavities. In some embodiments, the probe 110 is an intravascular ultrasound (IVUS) imaging catheter or an intracardiac echocardiography (ICE) catheter. In other embodiments, the probe 110 is a transesophageal echocardiography (TEE) probe. The probe 110 is in any preferred form for any preferred ultrasound imaging application, including both external and internal ultrasound imaging.

[0017] In some embodiments, aspects of the present disclosure can be carried out using medical images of a patient acquired using any suitable medical imaging device and / or modality. Examples of medical images and medical imaging devices include X-ray images (angiographic images, fluoroscopic images, images with or without contrast) acquired by an X-ray imaging device, computed tomography (CT) images acquired by a CT imaging device, positron emission tomography (PET-CT) images acquired by a PET-CT imaging device, magnetic resonance imaging (MRI) images acquired by an MRI device, single-photon emission computed tomography (SPECT) images acquired by a SPECT imaging device, optical coherence tomography (OCT) images acquired by an OCT imaging device, and intravascular photoacoustic (IVPA) images acquired by an IVPA imaging device. Medical imaging devices can acquire medical images while being located outside the patient's body, at a distance from the patient's body, adjacent to the patient's body, in contact with the patient's body, and / or inside the patient's body.

[0018] The transducer array 112 for an ultrasonic imaging device radiates an ultrasonic signal toward a patient's anatomical object 105 and receives an echo signal that is reflected from the object 105 and returns to the transducer array 112. The transducer array 112 can include any suitable number of acoustic elements, including one or more acoustic elements, and / or a plurality of acoustic elements. In some cases, the transducer array 112 includes a single acoustic element. In some cases, the transducer array 112 includes an array of acoustic elements that includes any number of acoustic elements of any suitable configuration. For example, the transducer array 112 can include values such as 2 acoustic elements, 4 acoustic elements, 36 acoustic elements, 64 acoustic elements, 128 acoustic elements, 500 acoustic elements, 812 acoustic elements, 1000 acoustic elements, 1920 acoustic elements, 3000 acoustic elements, 8000 acoustic elements, etc., and / or other values that are larger or smaller, and can include between 1 and 10,000 acoustic elements. In some cases, the transducer array 112 includes an array of acoustic elements that includes any number of acoustic elements of any suitable configuration, such as a linear array, a planar array, a curved array, an array surrounded by a curve, a circumferential array, an annular array, a phased array, a matrix array, a one-dimensional (1D) array, a 1.x-dimensional array (e.g., a 1.5D array), or a two-dimensional (2D) array. The array of acoustic elements (e.g., one or more rows, one or more columns, and / or one or more orientations) can be controlled and actuated uniformly or separately. The transducer array 112 can be configured to acquire one-dimensional, two-dimensional, and / or three-dimensional images of a patient's anatomical tissue. In some embodiments, the transducer array 112 includes piezoelectric micromachined ultrasonic transducers (PMUTs), capacitive micromachined ultrasonic transducers (CMUTs), single crystals, lead zirconate titanate (PZT), PZT composite materials, other suitable transducer types, and / or combinations thereof.

[0019] Object 105 includes any anatomical tissue or feature, such as diaphragms, blood vessels, nerve fibers, airways, mitral valves, cardiac structures, abdominal tissue structures, appendix, large intestine (or colon), small intestine, kidneys, liver, and / or any other anatomical tissue of the patient. In some embodiments, Object 105 includes at least a portion of the patient's large intestine, small intestine, cecal pouch, appendix, terminal ileum, liver, upper abdomen, and / or psoas muscle. This disclosure can be implemented in the context of any number of anatomical locations and tissue types, including, but not limited to, organs including the liver, heart, kidneys, gallbladder, pancreas, lungs, tubules, intestines, brain, dural sac, spinal cord and peripheral nerves, nervous system structures including the urinary tract and valves in blood vessels, blood, cardiac chambers or other parts of the heart, abdominal organs, and / or other systems of the body. In some embodiments, Object 105 includes malignant diseases such as tumors, cysts, trauma, hemorrhage, or blood pools in any part of human anatomical tissue. Anatomical tissues include arterial or venous vessels of the patient's vascular system, including cardiac vascular structures, peripheral vascular structures, neurovascular structures, renal vascular structures, and / or any other suitable lumens within the body. In addition to natural structures, this disclosure can be implemented in the context of artificial structures such as heart valves, stents, shunts, filters, implants, and other devices, but is not limited thereto.

[0020] The beamformer 114 is coupled to the transducer array 112. The beamformer 114 controls the transducer array 112, for example, for transmitting ultrasonic signals and for receiving ultrasonic echo signals. In some embodiments, the beamformer 114 applies a time delay to the signals sent to the individual acoustic transducers within the array in the transducer array 112 so that the acoustic signals propagate out of the probe 110 and are steered in any suitable direction. The beamformer 114 further supplies an image signal to the processor 116 based on the response of the received ultrasonic echo signals. The beamformer 114 includes a plurality of stages of beamforming. Beamforming can reduce the number of signal lines for coupling to the processor 116. In some embodiments, the transducer array 112, in combination with the beamformer 114, is referred to as an ultrasonic imaging component.

[0021] The processor 116 is coupled to the beamformer 114. The processor 116 is further described as a processor circuit that may include other components such as memory, the beamformer 114, a communication interface 118, and / or other suitable components that communicate with the processor 116. The processor 116 includes a central processing unit (CPU), a graphical processing unit (GPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a controller, a field-programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 116 is also implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. The processor 116 is configured to process the beamformed image signal. For example, the processor 116 performs filtering and / or quadrature demodulation to condition the image signal. The processors 116 and / or 134 can be configured to control the array 112 in order to acquire ultrasonic data associated with the object 105.

[0022] The communication interface 118 is coupled to the processor 116. The communication interface 118 includes one or more transmitters, one or more receivers, one or more transceivers, and / or circuit configurations for transmitting and / or receiving communication signals. The communication interface 118 may include hardware components and / or software components that implement a specific communication protocol suitable for carrying signals to the host 130 via the communication link 120. The communication interface 118 may be referred to as a communication device or a communication interface module.

[0023] Communication link 120 is any suitable communication link. For example, communication link 120 is a wired link such as a Universal Serial Bus (USB) link or an Ethernet link. Alternatively, communication link 120 is a wireless link such as an ultra-wideband (UWB) link, an IEEE 802.11 WiFi link, or a Bluetooth link.

[0024] In host 130, communication interface 136 receives image signals. Communication interface 136 is substantially similar to communication interface 118. Host 130 is any suitable computing device and display device, such as a workstation, personal computer (PC), laptop, tablet, or mobile phone.

[0025] The processor 134 is coupled to the communication interface 136. The processor 134 is further described as a processor circuit that may include other components such as memory 138, the communication interface 136, and / or other suitable components that communicate with the processor 134. The processor 134 is implemented as a combination of software and hardware components. The processor 134 includes a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 134 is also implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. The processor 134 can be configured to generate image data from an image signal received from the probe 110. The processor 134 can apply advanced signal processing and / or image processing techniques to the image signal. Examples of image processing include performing pixel-level analysis to evaluate whether there are color changes in pixels corresponding to the edges of an object (e.g., edges of anatomical features). In some embodiments, the processor 134 can form a three-dimensional (3D) volumetric image from the image data. In some embodiments, the processor 134 can perform real-time processing on the image data to provide a streaming video of the ultrasound image of the object 105.

[0026] Memory 138 is coupled to processor 134. Memory 138 is any suitable storage device such as cache memory (e.g., the cache memory of processor 134), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state memory device, hard disk drive, solid-state drive, other forms of volatile and non-volatile memory, or combinations of different types of memory.

[0027] Memory 138 can be configured to store not only the patient's medical history, history of procedures performed, patient information, measurements, data, or files relating to the patient's anatomical or biological features, characteristics, or medical conditions, as well as computer-readable instructions such as code, software, or other applications, but also any other suitable information or data. Memory 138 is located within host 130. Patient information includes, but is not limited to, measurements, data, files, and other forms of medical history such as ultrasound images, ultrasound footage, and / or any imaging information relating to the patient's anatomical tissues.

[0028] Any or all of the previously mentioned computer-readable media, such as patient information, code, software, or other applications, or any other suitable information or data, are further stored in memory 140. Memory 140 serves a substantially similar purpose to memory 138 but is not located within host 130. For example, in some embodiments, memory is a cloud-based server, an external storage device, or any other device for memory storage. Host 130 communicates with memory 140 by any preferred means as described. Host 130 communicates with memory 140 continuously or intermittently when requested by host 130 or when requested by a user of ultrasound system 100.

[0029] The host 130 communicates with the memory 140 by any preferred communication method. For example, the host 130 communicates with the memory 140 via a wired link such as a USB link or an Ethernet link. Alternatively, the host 130 communicates with the memory 140 via a wireless link such as a UWB link, an IEEE 802.11 WiFi link, or a Bluetooth link.

[0030] The display 132 is coupled to the processor circuit 134. The display 132 is a monitor or any suitable display. The display 132 is configured to display an ultrasound image, video image, and / or any imaging information of the object 105.

[0031] System 100 is used to assist the ultrasound technician in performing ultrasound scans. Scans are performed within or while in a point-of-care environment. In some cases, the host 130 is a console or a mobile cart. In some cases, the host 130 is a portable device such as a tablet, mobile phone, or portable computer.

[0032] Figure 2 is a schematic diagram of a processor circuit 210 according to an aspect of the present disclosure. The processor circuit 210 is implemented in the probe 110, the host system 130 in Figure 1, or any other preferred location. One or more processor circuits can be configured to perform the operations described herein. The processor circuit 210 may be part of circuit configuration 116 and / or circuit configuration 134, or it may be a separate circuit configuration. In an example, the processor circuit 210 communicates with the transducer array 112, the beamformer 114, the communication interface 118, the communication interface 136, the memory 138, the memory 140, and / or the display 132, and any other preferred components or circuits in the ultrasonic system 100. As shown, the processor circuit 210 includes a processor 260, a memory 264, and a communication module 268. These elements communicate directly or indirectly with each other, for example, via one or more buses.

[0033] The processor 260 includes a CPU, GPU, DSP, application-specific integrated circuit (ASIC), controller, FPGA, other hardware device, firmware device, or any combination thereof configured to perform the operations described herein. The processor 260 is further implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. The processor 260 further implements various deep learning networks, including hardware or software implementations.

[0034] Memory 264 includes cache memory (e.g., the cache memory of processor 260), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state memory devices, hard disk drives, other forms of volatile and non-volatile memory, or combinations of different types of memory. In embodiments, memory 264 includes non-temporary computer-readable media. Memory 264 stores instructions 266. Instructions 266, when executed by processor 260, include instructions that cause processor 260 to perform operations described herein with reference to probe 110 and / or host 130 (Figure 1). Instructions 266 are also referred to as code. The terms “instruction” and “code” should be interpreted broadly to include any type of computer-readable statement. For example, the terms “instruction” and “code” refer to one or more programs, routines, subroutines, functions, procedures, etc. “Instruction” and “code” include a single computer-readable statement or many computer-readable statements. Instruction 266 includes various aspects of image generation, such as the coherent joining of multiple subframes of an image, or various other instructions or code.

[0035] The communication module 268 may include any electronic and / or logic circuit configurations to facilitate direct or indirect data communication between the processor circuit 210, the probe 110, and / or the display 132. In this regard, the communication module 268 may be an input / output (I / O) device. In some cases, the communication module 268 facilitates direct or indirect communication between various elements of the processor circuit 210, the probe 110 (Figure 1), and / or the host 130 (Figure 1).

[0036] Figure 3 shows an exemplary ultrasonic image 300 (e.g., a B-mode ultrasonic image) acquired without transmitting beam steering (e.g., at a beam steering angle of 0°). In particular, Figure 3 shows an ultrasonic image acquired by transmitting ultrasonic energy along a linear path (e.g., perpendicularly) from a transducer array such as transducer array 112 (Figure 1). For this purpose, the ultrasonic image 300 is produced based on echoes associated with the ultrasonic energy reflected by the imaged object. As further shown, the ultrasonic image 300 is shown with respect to an axial distance representing the distance from the transducer array (e.g., depth) and a lateral distance corresponding to the position along the transducer array (e.g., the position of the acoustic elements of the transducer array), with the axial distance shown in centimeters (cm). The intensity of the ultrasonic imaging data (e.g., received echoes) is further shown in decibels (dB) by a color-coded scale 302.

[0037] In some cases, ultrasound images contain distortions such as noise and / or lack of resolution, which limit the accuracy, reliability, and / or usefulness of ultrasound imaging for clinical purposes. For example, ultrasound images may appear as noise and / or distortion, including speckle resulting from the irregular scattering of ultrasound energy and / or echoes. As an exemplary example, within region 310 (e.g., the near-field region) of ultrasound image 300, speckle appears as a grainy or noisy appearance. Thus, within region 310, ultrasound image 300 includes a non-uniform background due to the speckle. Furthermore, the resolution of ultrasound images varies across the depth of the image (with respect to the axial distance acquired). For example, points in region 320 (e.g., the far-field region), which covers a relatively greater depth, appear less resolved compared to points in region 310, which covers a relatively shallow depth. In particular, the contours of objects 330 appear spread out and blurred instead of appearing as relatively resolved (e.g., sharp) circles. Therefore, distortion in ultrasound images, as indicated by the speckles and lack of resolution in each of the ultrasound images 300 (for regions 310 and 320 respectively), obscures the features of the imaged object, which affects the clinician's ability to interpret the image and / or make an accurate diagnosis.

[0038] Figure 4 illustrates the generation of an effective aperture 410 from a set of sub-apertures 420. In particular, Figure 4 shows the use of different subsets of acoustic elements of a transducer array (e.g., transducer array 112) to reconstruct (e.g., create) an effective aperture 410 across the open apertures of the transducer array (e.g., apertures using each of the acoustic elements of the transducer array). For example, each of the sub-apertures 422a-d is created by activating a subset of acoustic elements of the transducer array. More specifically, each shaded portion of sub-apertures 422a-d represents an acoustic element of the transducer array used to transmit ultrasonic energy and receive echoes associated with the transmitted ultrasonic energy, while each unshaded portion of sub-apertures 422a-d represents the remaining acoustic elements in the transducer array. In some embodiments, first ultrasonic data is acquired using a first sub-aperture 422a of the transducer array at a first time step, second ultrasonic data is acquired using a second sub-aperture 422b of the transducer array at a second time step, third ultrasonic data is acquired using a third sub-aperture 422c of the transducer array at a third time step, and fourth ultrasonic data is acquired using a fourth sub-aperture 422d of the transducer array at a fourth time step. For example, acoustic elements corresponding to the set of sub-apertures are operated sequentially (e.g., used to transmit ultrasonic energy). Furthermore, the first, second, third, and fourth ultrasonic data correspond to subframes of an ultrasonic image. That is, for example, an image (e.g., an image frame) is generated based on the combination of subframes corresponding to each of the set of sub-apertures 420. Furthermore, the generated image corresponds to an image generated using an effective aperture 410. For example, the width of the generated image corresponds to the width of an image generated using the open aperture of the transducer array.

[0039] Figures 5A and 5B further illustrate the use of sub-apertures for generating images. In particular, Figure 5A shows the use of a first sub-aperture 510a of the transducer array 520 for imaging an object 530, which is substantially similar to sub-apertures 422a-d, and the transducer array 520 is substantially similar to the transducer array 112. Figure 5B shows the use of a second sub-aperture 510b of the transducer array 520 for imaging an object 530. As further shown, each of the sub-apertures 510a-b is used to transmit ultrasonic energy using a plurality of angles 540 (e.g., a plurality of beam steering angles). That is, for example, beam steering transmission is used for transmitting ultrasonic energy from sub-apertures 510a-d. In some embodiments, for example, beam steering angles of 0°, 5°, -5°, 10°, -10° or any other preferred angle are used to transmit ultrasonic energy.

[0040] In some embodiments, the ultrasonic image data resulting from the transmission of ultrasonic energy in different combinations of sub-apertures (510a-b) and angles among a plurality of angles 540 is combined (e.g., synthesized) to correspond to each subframe of a set of subframes that generate an image of the object 530. As an exemplary example, ultrasonic image data acquired through the first sub-aperture 510a using the first angle 540a corresponds to the first subframe of the image of the object 530, and ultrasonic image data acquired through the second sub-aperture 510b using the second angle 540b corresponds to the second subframe of the image of the object 530. Thus, both the first and second subframes capture features of the same object (e.g., object 530) from their respective sub-apertures and angles. Furthermore, the combination of the first and second subframes reduces distortion in the resulting image compared to an image generated using a single aperture and / or a single angle to transmit ultrasonic energy. An example of image data merging is described in U.S. Patent No. 8,317,712, titled "Retrospective Dynamic Transmit Focusing for Spatial Compounding," filed on April 17, 2017, which is incorporated herein by reference in its entirety. Mechanisms for merging (e.g., compositing) subframes of an image are described in more detail herein.

[0041] Figure 6 is a block diagram of a signal path 600 for generating an ultrasound image using incoherent coupling of a set of subframes, according to an embodiment of the present disclosure. The signal path 600 is associated with a method or process for image generation. It will be understood that the elements of the signal path 600 comprise computer program code or instructions executable by a processor circuit, such as the processor circuit 210 shown in Figure 2. For example, in some embodiments, the elements of the signal path 600 comprise different processing (e.g., software) modules. In some embodiments, the elements of the signal path 600 comprise different hardware components.

[0042] In some embodiments, the components and / or operations of the signal path 600 are implemented by the probe 110 and / or host 130 shown in Figure 1. In particular, the components of the signal path 600 are implemented by the beamformer 114, processor 116, communication interface 118, communication interface 136, and / or processor 134. In some embodiments, for example, the components of the signal path 600 are distributed between the probe 110 and the host 130. Furthermore, the components of the signal path 600 are implemented through a combination of hardware and software components and are executed by the processor circuit 210 described above with respect to Figure 2. For example, in some embodiments, one or more components and / or operations of the signal path 600 can be executed by a GPU.

[0043] In some embodiments, ultrasonic data is received (e.g., input) to a signal path 600. For example, the signal path 600 receives data corresponding to a set of subframes based on received echoes associated with ultrasonic energy transmitted by an array of acoustic elements (e.g., transducer array 112). In particular, the data corresponding to a set of subframes is associated with echoes associated with ultrasonic energy transmitted by a set of subapers described herein and / or at different angle sets. The data corresponding to a set of subframes includes analog or digital data. For example, in some cases, the signal path 600 receives raw analog electrical signals from the array of acoustic elements. In such cases, one or more operations of the signal path 600 are performed on the analog signals. Additionally or alternatively, the signal path 600 includes, or communicates with, an analog-to-digital converter (ADC), which samples the analog signals to supply digital subframe data.

[0044] As illustrated, the signal path 600 includes a beamformer 610. The beamformer 610 is substantially similar to the beamformer 114 in Figure 1. Therefore, in some embodiments, the beamformer 610 is included in the ultrasonic probe (e.g., probe 110). In some cases, data corresponding to a set of subframes is beamformed by the beamformer 610. For example, the beamformer 610 performs a coherent delay-total operation on the data to supply a beamformed signal. In some embodiments, the beamformer 610 includes multiple stages of beamforming. Furthermore, in some embodiments, beamforming can reduce the number of signal lines associated with the data corresponding to a set of subframes for coupling to a host (e.g., host 130). Moreover, as mentioned above, the data corresponding to a set of subframes includes analog or digital signals. Therefore, the beamformer 610 performs beamforming on data in either the analog or digital domain, or both.

[0045] After the data corresponding to the set of subframes has been beamformed, the data corresponding to the set of subframes is output to the envelope detection module 620. The envelope detection module 620 is implemented as an envelope detector (e.g., a rectifier and / or filter) that outputs the envelope of the data corresponding to the set of subframes. Since the envelope of the data corresponding to the set of subframes corresponds to amplitude rather than phase information associated with the data, the envelope detection module 620 suppresses or removes the phase information associated with the data corresponding to the set of subframes.

[0046] In addition to, or alternatively to, the ultrasonic imaging system 100 including an envelope detector for the envelope detection module 620, a beamformer 114 performs baseband conversion and / or demodulation on data corresponding to a set of subframes. In some embodiments, the beamformer 114 includes a rectifier configured to convert real-valued RF samples in the image signal to a baseband (BB) signal, or data including composite in-phase, quadrature-phase (IQ) pairs. The rectifier performs down-conversion, low-pass filtering, and / or decimation. Down-conversion converts the RF output signal data from RF to BB by, for example, downmixing the RF signal with two sinusoidal signals having a 90-degree phase difference. Thus, envelope detection is performed in the beamformer 114. Additionally, or alternatively, a GPU (e.g., processor circuit 210) is implemented to perform envelope detection or a portion of envelope detection on data corresponding to a set of subframes.

[0047] The signal path 600 further includes a log compression module 630 configured to perform log compression on data corresponding to a set of subframes. More specifically, the log compression module 630 performs log compression on data corresponding to a set of subframes after envelope detection has been performed (for example, by an envelope detection module 620). To this end, log compression is applied to the envelope of data corresponding to a set of subframes, thereby capturing amplitude rather than phase information associated with the data corresponding to the set of subframes. In some embodiments, a processor circuit, such as the processor circuit 210 in Figure 2, implements the log compression module 630. In some embodiments, for example, a GPU performs log compression on data corresponding to a set of subframes.

[0048] The scan transformation module 640 is coupled to the log compression module 630 and performs scan transformation on the image data output by the log compression module 630 (e.g., data corresponding to a set of subframes) to a suitable display format. In an example, the image data is in polar coordinates, and the scan transformation module 640 transforms the image data into Cartesian coordinates for display. In some embodiments, a processor circuit, such as the processor circuit 210 in Figure 2, implements the scan transformation module 640. In some embodiments, for example, a GPU performs scan transformation on the data corresponding to a set of subframes.

[0049] The signal path 600 further includes an incoherent coupling module 650. The incoherent coupling module 650 is configured to incoherently combine (e.g., synthesize) data corresponding to a set of subframes. For example, the incoherent coupling module 650 incoherently combines the data corresponding to a set of subframes by summing (e.g., averaging) the data corresponding to the first subframe of the set of subframes and the data corresponding to the second subframe of the set of subframes. Furthermore, the incoherent combination of image data corresponds to the sum (e.g., average) of phase-inactive data corresponding to the set of subframes. For this reason, although the illustrated incoherent coupling module is located at the end of the signal path, the incoherent coupling module can be additionally or alternatively located at any part of the signal path 600, such as any part of the signal path 600 following envelope detection (e.g., in the envelope detection module 620), where the data corresponding to a set of subframes lacks phase information.

[0050] In some embodiments, the incoherent coupling module 650 is implemented as a totalizer, such as a digital or analog totalizer. Additionally or alternatively, a processor circuit, such as the processor circuit 210 in Figure 2, implements the incoherent coupling module 650. In some embodiments, for example, a GPU incoherently combines data corresponding to a set of subframes.

[0051] While the signal path 600 is illustrated and described herein to include a particular set of components and / or be involved in a particular operation, embodiments are not limited thereto. For this purpose, additional components and / or operations may be included, and / or components and / or operations may be omitted. For example, the signal path 600 may additionally or alternatively include an ADC (e.g., including analog-to-digital converters), any suitable filters (e.g., low-pass filters, high-pass filters, and / or band-pass filters), buffers for temporarily storing and / or copying data, and / or memory devices. In some embodiments, for example, image data is buffered in the buffer until data corresponding to each of a set of subframes is received in the signal path 600 and / or received in a particular portion of the signal path 600. Furthermore, while the signal path 600 is illustrated in a particular order, one or more of the components and / or operations may be performed in a different order or in parallel.

[0052] Figure 7 shows an exemplary ultrasound image 700 (e.g., a B-mode ultrasound image) generated based on incoherent coupling of data corresponding to a set of subframes using the techniques described herein with respect to Figures 4, 5A, 5B, and 6. In particular, the ultrasound image 700 is generated using one or more subapers and / or beam steering angles, and the resulting incoherent coupling of subframes. For this purpose, the ultrasound image 700 is produced by the signal path 600 in Figure 6. As further shown, the ultrasound image 700 is shown with respect to an axial distance representing the distance from the transducer array (e.g., depth) and a lateral distance corresponding to the position along the transducer array (e.g., the position of the acoustic elements on the transducer array), with the axial distance shown in centimeters (cm). The intensity of the ultrasound imaging data (e.g., received echoes) is further shown in decibels (dB) by a color-coded scale 702.

[0053] Compared to ultrasound image 300 in Figure 3, the speckle present in ultrasound image 700 is reduced. In particular, region 710 of ultrasound image 700 (e.g., the near-field region) is less distorted than region 310 of ultrasound image 300. This improvement in image quality is brought about by the incoherent combination of data corresponding to subframes of ultrasound image 700. More specifically, since multiple subframes contain data associated with specific locations in the imaging field (e.g., as shown in Figures 5A and 5B), the combination of subframes smooths (averages) noise such as speckle from the resulting composite image.

[0054] Speckle is reduced in the near-field portion of the ultrasound image 700, but as the depth of the ultrasound image 700 increases, the resolution decreases as described above with reference to Figure 3. Therefore, in some embodiments, additional or alternative techniques are used to improve the resolution of the ultrasound image. For example, the resolution of an ultrasound image depends in part on the phase interference between the subframes synthesized in the image. For this reason, incoherent coupling is performed without phase information about the subframes, so a mechanism for coherently coupling data corresponding to subframes to produce a better-resolved ultrasound image is described herein.

[0055] Figure 8 is a flowchart of Method 800, according to an aspect of the present disclosure, for coherently combining data corresponding to a set of subframes for generating an ultrasound image (e.g., a composite ultrasound image). As illustrated, Method 800 includes several enumerated steps, but embodiments of Method 800 include additional steps before, after, or between the enumerated steps. In some embodiments, one or more of the enumerated steps are omitted, performed in a different order, or performed simultaneously. The steps of Method 800 can be performed by any preferred component within the ultrasound imaging system 100, and not all steps need to be performed by the same component. In some embodiments, one or more steps of Method 800 can be performed by, for example, a processor circuit of the ultrasound imaging system 100, including a processor 260 (Figure 2) or any other component, or at the direction of the processor circuit.

[0056] Step 802 of Method 800 includes controlling an array of acoustic elements to transmit ultrasonic energy and receive echoes associated with the ultrasonic energy. In some embodiments, for example, the ultrasonic imaging system 100 controls the transducer array 112 of the probe 110 to transmit first ultrasonic energy using a first subset of the array of acoustic elements (e.g., a first sub-aperture) and to transmit second ultrasonic energy using a second subset of the array of acoustic elements (e.g., a second sub-aperture). The first subset is distinct from the second subset. In some cases, the first and second subsets are completely separate (e.g., spaced apart from each other) or overlap (e.g., sharing acoustic elements). Furthermore, step 802 involves receiving echoes associated with the first ultrasonic energy and echoes associated with the second ultrasonic energy, corresponding to the first and second subframes, respectively. For example, a first portion of the received echo (e.g., the received echo associated with ultrasonic energy) corresponds to a first ultrasonic energy, and a second portion of the received echo corresponds to a second ultrasonic energy. Furthermore, in some embodiments, the array of acoustic elements is controlled to use a first subset of acoustic elements to receive echoes associated with a first ultrasonic energy and a second subset of acoustic elements to receive echoes associated with a second ultrasonic energy.

[0057] Step 804 involves Method 800 receiving data corresponding to a set of subframes based on the received echoes. The data corresponding to the set of subframes includes data corresponding to a first subframe and a second subframe, as described above, where the first and second subframes correspond to the echo associated with a first ultrasonic energy and the echo associated with a second ultrasonic energy, respectively. Furthermore, the data corresponding to the first and second subframes correspond to image data corresponding to the same object (e.g., an anatomical object) collected through the respective sub-apertures and / or beam steering angles, as described above with reference to Figures 4 and 5A-5B. In some embodiments, the data corresponding to the set of subframes is analog data, such as analog electrical signals from an array of acoustic elements. In some embodiments, the data corresponding to the set of subframes is digital data. For example, in such embodiments, the analog electrical signals from an array of acoustic elements are sampled into a digital signal (e.g., a digital data signal) by an ADC. Furthermore, in some cases, the data corresponding to the set of subframes is in the form of radio frequency (RF) data. In addition, the data corresponding to the set of subframes includes both phase and amplitude information.

[0058] Step 806 involves coherently combining the first portion of the first subframe and the first portion of the second subframe. More specifically, step 806 involves coherently combining the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe. Both the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe contain phase information. That is, for example, in order to coherently combine the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe, the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe are combined, and then envelope detection is performed on the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe, and / or phase information is removed from the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe. In some embodiments, the first portion of the first subframe and the first portion of the second subframe are coherently coupled by a GPU included in, for example, the host 130 and / or probe 110. Furthermore, it is understood that the first portion of the first subframe and the first portion of the second subframe refer to the entire first and second subframes, or to subsets of pixels of the first and second subframes, respectively.

[0059] Step 808 involves method 800 generating an image (e.g., a synthesized ultrasound image) based on the coherent coupling of the first and second subframes. In some embodiments, the image is generated based on beamforming, envelope detection, log compression, and / or scan transformation of the data corresponding to the first and second subframes. For example, the image is generated according to the signal path in the ultrasound imaging system 100, as described with reference to Figure 9.

[0060] Next, moving to Figure 9, a signal path 900 is shown, which is included in an ultrasound imaging system (e.g., ultrasound imaging system 100) and used to generate ultrasound image data and / or ultrasound images. In particular, the signal path 900 is used to generate ultrasound images based on the coherent coupling of a set of subframes. The signal path 900 is associated with a method or process for image generation. It will be understood that the elements of the signal path 900 comprise computer program code or instructions that can be executed by a processor circuit, such as the processor circuit 210 shown in Figure 2. For example, in some embodiments, the elements of the signal path 900 comprise different processing (e.g., software) modules. In some embodiments, the elements of the signal path 900 comprise different hardware components.

[0061] In some embodiments, the components and / or operations of the signal path 900 are implemented by the probe 110 and / or host 130 shown in Figure 1. In particular, the components of the signal path 900 are implemented by the beamformer 114, processor 116, communication interface 118, communication interface 136, and / or processor 134. In some embodiments, for example, the components of the signal path 900 are distributed between the probe 110 and the host 130. Furthermore, the components of the signal path 900 are implemented through a combination of hardware and software components and are executed by the processor circuit 210 described above with respect to Figure 2. For example, in some embodiments, one or more components and / or operations of the signal path 900 can be executed by a GPU.

[0062] In some embodiments, ultrasonic data is received (e.g., input) to a signal path 900. For example, the signal path 900 receives data corresponding to a set of subframes based on received echoes associated with ultrasonic energy transmitted by an array of acoustic elements (e.g., transducer array 112). In particular, the data corresponding to a set of subframes is associated with echoes associated with ultrasonic energy transmitted by a set of subapers described herein and / or at different angle sets. The data corresponding to a set of subframes includes analog or digital data. For example, in some cases, the signal path 900 receives raw analog electrical signals from the array of acoustic elements. In such cases, one or more operations of the signal path 900 are performed on the analog signals. Additionally or alternatively, the signal path 900 includes, or communicates with, an analog-to-digital converter (ADC), which samples the analog signals to supply digital subframe data.

[0063] As illustrated, the signal path 900 includes a beamformer 610. As described with reference to Figure 6, the beamformer 610 is substantially similar to the beamformer 114 in Figure 1. Therefore, data corresponding to a set of subframes is beamformed by the beamformer 610. For example, the beamformer 610 performs a coherent delay-total operation on the data to supply the beamformed signal.

[0064] After the data corresponding to the set of subframes has been beamformed, the data corresponding to the set of subframes is output to the scan transformation module 640. The scan transformation module 640 performs a scan transformation on the image data output by the beamformer 610 (e.g., the data corresponding to the set of subframes) to a suitable format for coherent concatenation and / or alignment. For example, the scan transformation module 640 transforms the image data to a format used by a processor circuit (e.g., processor circuit 210) to sum the subframes and / or align the subframes. Additionally or alternatively, the scan transformation module 640 performs a scan transformation on the image data to a suitable display format. For example, if the image data is in polar coordinates, the scan transformation module 640 transforms the image data to Cartesian coordinates for display. In some embodiments, a processor circuit such as processor circuit 210 in Figure 2 implements a log compression module 630. In some embodiments, for example, a GPU performs a scan transformation on the data corresponding to the set of subframes.

[0065] Following the scan transformation, the signal path 900 includes an alignment module 910. As indicated by the dashed boundary, the alignment module 910 is optionally included in the signal path 900. The alignment module 910 is implemented by a processor circuit (e.g., processor circuit 210), such as a GPU, to precisely align the subframes with each other before totalization (e.g., coherent coupling). More specifically, the alignment module 910 spatially aligns a set of subframes with each other. This alignment involves identifying common and / or reference features across different subframes, and relating data points associated with these features across different subframes. In some embodiments, the alignment involves relating subframes acquired with the same subaperture and the same beam steering angle. Additionally, or alternatively, the alignment of subframes with each other involves the use of data from another sensor or device, such as a position tracking system (e.g., an electromagnetic tracking system, and / or an optical tracking system), which can determine the position of the ultrasonic probe when each subframe was acquired. For example, a set of subframes is associated with each other based on the determined position of the ultrasound probe.

[0066] In some embodiments, mismatches exist between subframes capturing the same features. In an illustrative example, two subframes of the same object acquired using the same secondary aperture and the same beam steering angle may vary from one another due to patient and / or probe movement, or another source of error (e.g., system error and / or random error). Since coherent coupling is highly sensitive to alignment errors, such mismatches limit the effectiveness of coherent coupling of subframes. That is, for example, mismatches between coherently coupled subframes affect the interaction (e.g., interference) of phase information corresponding to different subframes, which results in the generation of an ultrasound image different from what would normally be produced. In some embodiments, mismatches are reduced by calibrating the ultrasound imaging system 100. For example, errors guided by the probe 110 and / or host 130 are identified by imaging phantom points, and calibration corrections are applied for future imaging applications. To further compensate for misalignments, after alignment of the subframes relative to each other and / or their locations, the alignment module 910 adjusts the data corresponding to the set of subframes to align the set of subframes relative to each other based on the alignment. For example, the alignment module 910 is configured to compensate for misalignments resulting from motion in the set of subframes. In some embodiments, the alignment module 910 is configured to determine an adjustment (e.g., a correction factor) to compensate for such misalignments based on sequentially acquired subframes collected using the same subaperture and beam steering angle. An example of motion detection and compensation (e.g., misalignment compensation) is described in U.S. Patent No. 9,345,455, titled "Ultrasonic Synthetic Transmit Focusing with Motion Compensation," filed October 29, 2015, which is incorporated herein by reference in its entirety.

[0067] The signal path 900 further includes a coherent coupling module 920. The coherent coupling module 920 is configured to coherently combine (combine) data corresponding to a set of subframes. For example, the coherent coupling module 920 coherently combines the data corresponding to a set of subframes by summing (e.g., averaging) the data corresponding to a first subframe of the set of subframes and the data corresponding to a second subframe of the set of subframes. Furthermore, the coherent combination of image data corresponds to the sum (e.g., averaging) of data containing phase information corresponding to the set of subframes. Thus, when combined, the phase information from the first subframe interacts (e.g., interferes) with the phase information from the second subframe. Furthermore, while the example coherent coupling module 920 is positioned at a specific point within the signal path 900, the coherent coupling module 920 may also be positioned in any portion of the signal path 900, either additionally or alternatively, within any portion of the signal path 900, such as any portion of the signal path 900 prior to envelope detection (e.g., envelope detection module 620), where data corresponding to a set of subframes includes phase information.

[0068] In some embodiments, the coherent coupling module 920 is implemented as a totalizer, such as a digital totalizer or an analog totalizer. Additionally or alternatively, a processor circuit, such as the processor circuit 210 in Figure 2, implements the coherent coupling module 920. In some embodiments, for example, a GPU coherently couples data corresponding to a set of subframes.

[0069] Following the coherent coupling of data corresponding to a set of subframes, envelope detection is performed on the data corresponding to the set of subframes by the envelope detection module 620. As described above with reference to Figure 6, the envelope detection module is implemented as an envelope detector (e.g., a rectifier and / or filter) that outputs the envelope of the data corresponding to the set of subframes. Additionally or alternatively, envelope detection is performed by a beamformer (e.g., beamformer 114) and / or a processor circuit such as a GPU (e.g., processor circuit 210).

[0070] The signal path 900 further includes a log compression module 630 configured to perform log compression on the data corresponding to a set of subframes. More specifically, the log compression module 630 performs log compression on the data corresponding to a set of subframes after envelope detection has been performed (for example, by an envelope detection module 620). In some embodiments, a processor circuit, such as the processor circuit 210 in Figure 2, implements the log compression module 630. In some embodiments, for example, a GPU performs log compression on the data corresponding to a set of subframes.

[0071] As further illustrated, the signal path 900 optionally includes an additional scan transformation module 930 coupled to the log compression module 630. The scan transformation module 930 is the same as or different from the scan transformation module 640. In some embodiments, the scan transformation module 930 performs additional scan transformations on data corresponding to a set of subframes to optimize the format of the image data and / or complete the scan transformation of the image data. For example, in some embodiments, the scan transformation module 640 performs partial scan transformations (e.g., partial transformation, transformation to an intermediate format, transformation of a portion of a set of subframes), and the scan transformation module 930 completes the scan transformation of the data corresponding to the set of subframes to a format suitable for display. In some embodiments, a processor circuit, such as the processor circuit 210 in Figure 2, implements the scan transformation module 930. In some embodiments, for example, a GPU performs scan transformations on data corresponding to a set of subframes.

[0072] While the signal path 900 is illustrated and described herein to include a particular set of components and / or be involved in a particular operation, embodiments are not limited thereto. For this purpose, additional components and / or operations may be included, and / or components and / or operations may be omitted. For example, the signal path 900 may additionally or alternatively include an ADC (e.g., including analog-to-digital converters), any suitable filters (e.g., low-pass filters, high-pass filters, and / or band-pass filters), buffers for temporarily storing and / or copying data, and / or memory devices. In some embodiments, for example, image data is buffered in the buffer until data corresponding to each of a set of subframes is received in the signal path 900 and / or received in a particular portion of the signal path 900. Furthermore, while the signal path 900 is illustrated in a particular order, one or more of the components and / or operations may be performed in a different order or in parallel.

[0073] Figure 10 shows an exemplary ultrasound image 1000 (e.g., a B-mode ultrasound image) generated based on the coherent coupling of data corresponding to a set of subframes using the techniques described herein with respect to Figures 4, 5A, 5B, 8, and 9. In particular, the ultrasound image 1000 is generated using one or more subapers and / or beam steering angles, and the resulting coherent coupling of subframes. For this purpose, the ultrasound image 1000 is produced by the signal path 900 in Figure 9. As further shown, the ultrasound image 1000 is shown with respect to an axial distance representing the distance from the transducer array (e.g., depth) and a lateral distance corresponding to the position along the transducer array (e.g., the position of the acoustic elements on the transducer array), with the axial distance shown in centimeters (cm). The intensity of the ultrasound imaging data (e.g., received echoes) is further shown in decibels (dB) by a color-coded scale 1002. The resolution of the ultrasound image 1000 is improved compared to the ultrasound image 300 in Figure 3. In particular, the resolution within region 1020 (e.g., the far-field region) of ultrasound image 1000 is higher than the resolution within regions 320 and 720, respectively, of ultrasound image 300 and ultrasound image 700 (Figure 7). For example, the contour of object 1030 is much sharper and more clearly identifiable than the contours of objects 330 and 730. In other words, the point spread of object 1030 in ultrasound image 1000 is minimized compared to the point spread of objects 330 and 730. More specifically, since multiple subframes contain data associated with specific locations in the imaging field (e.g., as shown in Figures 5A and 5B), the coherent combination of subframes averages out the point spread (e.g., resolution distortion) from the resulting composite image.

[0074] The resolution of the ultrasound image 1000 is noticeably improved, particularly in the far-field region (e.g., region 1020), but speckle remains present and clearly visible in the near-field portion of the ultrasound image 1000 (e.g., region 1010). That is, for example, the speckle (e.g., noise) in region 1010 is larger than the speckle in region 710 of ultrasound image 700, but substantially the same as the speckle in region 310 of ultrasound image 300. Therefore, in some embodiments, combinations of the techniques described herein are used to both improve resolution and reduce speckle present in the ultrasound image.

[0075] Returning to Figure 8, in some embodiments, image generation (e.g., in step 808) is performed based on coherent summation of data corresponding to subframes and incoherent summation of data corresponding to subframes. For example, in some embodiments, as will be described in more detail below with reference to Figure 11, a first image is generated based on coherent summation of data corresponding to subframes, a second image is generated based on incoherent summation of data corresponding to subframes, and an image (e.g., a third image) is based on the summation of the first and second images. Using the first and second images, a third image is formed based, for example, on the application of pixel-level weighting (e.g., masking) to the first and second images and the sum of the weighted images. Additionally, or alternatively, as will be described in more detail below with reference to Figure 12, an image is generated based on coherent summation of a first portion of data corresponding to a set of subframes, incoherent summation of a second portion of data corresponding to a set of subframes, and the summation of the first and second portions to form an image. For example, each part corresponds to a subset of the set of subframes and / or a subset of the data corresponding to a particular subframe (e.g., data corresponding to a region or set of pixels within a subframe). As in the example, five of the ten subframes are coherently summed, and the remaining five are incoherently summed, and the image is formed based on these two sums. As in the additional example, the top halves of two subframes are incoherently summed, but the bottom halves of two subframes are coherently summed, and the image is formed from these two sums.

[0076] Figure 11 is a block diagram of a signal path 1100 included in an ultrasound imaging system (e.g., ultrasound imaging system 100) and used to generate ultrasound image data and / or ultrasound images. In particular, the signal path 1100 is used to generate ultrasound images based on coherent coupling of sets of subframes and incoherent coupling of sets of subframes. The signal path 1100 is associated with a method or process for image generation. It will be understood that the elements of the signal path 1100 comprise computer program code or instructions executable by a processor circuit, such as the processor circuit 210 shown in Figure 2. For example, in some embodiments, the elements of the signal path 1100 comprise different processing (e.g., software) modules. In some embodiments, the elements of the signal path 1100 comprise different hardware components.

[0077] In some embodiments, the components and / or operations of the signal path 1100 are implemented by the probe 110 and / or host 130 shown in Figure 1. In particular, the components of the signal path 1100 are implemented by the beamformer 114, processor 116, communication interface 118, communication interface 136, and / or processor 134. In some embodiments, for example, the components of the signal path 1100 are distributed between the probe 110 and the host 130. Furthermore, the components of the signal path 1100 are implemented through a combination of hardware and software components and are executed by the processor circuit 210 described above with respect to Figure 2. For example, in some embodiments, one or more components and / or operations of the signal path 1100 can be executed by a GPU.

[0078] In some embodiments, ultrasonic data is received (e.g., input to) a signal path 1100. For example, the signal path 1100 receives data corresponding to a set of subframes based on received echoes associated with ultrasonic energy transmitted by an array of acoustic elements (e.g., transducer array 112). In particular, the data corresponding to a set of subframes is associated with echoes associated with ultrasonic energy transmitted by a set of subapers described herein and / or at different angle sets. The data corresponding to a set of subframes includes analog or digital data. For example, in some cases, the signal path 1100 receives raw analog electrical signals from the array of acoustic elements. In such cases, one or more operations of the signal path 1100 are performed on the analog signals. Additionally or alternatively, the signal path 1100 includes, or communicates with, an analog-to-digital converter (ADC), which samples the analog signals to supply digital subframe data.

[0079] In short, the signal path 1100 includes a first signal path 1102 implemented to generate first image data based on a coherent combination of data corresponding to a set of subframes, and a second signal path 1104 implemented to generate second image data based on an incoherent combination of data corresponding to a set of subframes. The signal path 1100 is further implemented to generate an ultrasound image based on the first and second image data (e.g., via an image generation module 1150). As illustrated, together with the beamformer 610, the first signal path 1102 is substantially similar to the signal path 900 shown in Figure 9, and the second signal path 1104 is substantially similar to the signal path 600 shown in Figure 6. Therefore, for brevity, the details of the components of the first signal path 1102 and the second signal path 1104 described above will not be repeated with reference to Figures 9 and 6, respectively.

[0080] In some embodiments, the signal path 1100 includes a buffer 1110. The buffer 1110 includes a memory device configured to temporarily store beamformed image data (e.g., received from a beamformer 610) for further processing. The buffer 1110 comprises a volatile memory resource accessible from either a single processing unit (e.g., a CPU core or FPGA) or a shared memory accessible from multiple processors (e.g., multiple cores, GPUs, and / or multiple paths within an FPGA). In some embodiments, the buffer 1110 includes a duplicater configured to duplicate image data to be processed along different processing paths, such as a first signal path 1102 and a second signal path 1104.

[0081] After receiving each image data from buffer 1110, the first signal path 1102 generates first image data based on a coherent combination of data corresponding to a set of subframes, and the second signal path 1104 generates second image data based on an incoherent combination of data corresponding to a set of subframes. In this way, the first signal path 1102 generates image data substantially similar to the ultrasound image 1000 in Figure 10, and the second signal path generates image data substantially similar to the ultrasound image 700 in Figure 7. In some embodiments, the processing paths are configured to perform operations on each image data simultaneously (e.g., in parallel) or at different times.

[0082] The first image data and the second image data are received by the image generation module 1150, which combines the first image data and the second image data to generate a composite ultrasound image. In some embodiments, the image generation module 1150 combines the first image data and the second image data by summing them together to form an ultrasound image. In some embodiments, the image generation module 1150 weights (masks) the data of the first image data and / or the second image data to perform a weighted sum of the dataset. Pixel-level weighting, such as linear or nonlinear weighting, is applied to the data corresponding to pixels in the first and / or second image data, as in the illustrative examples. In particular, the first image data and / or the second image data are weighted based on the spatial frequency of pixels in the image data and / or the location (e.g., depth) of pixels in the data.

[0083] In spatial frequency-based weighting, pixels associated with relatively lower spatial frequencies are weighted such that a second image data set (e.g., incoherently summed image data) has a greater contribution to the image than a first image data set (e.g., coherently summed image data), while pixels associated with relatively higher spatial frequencies are weighted such that a first image data set (e.g., coherently summed image data) has a greater contribution to the image than a second image data set (e.g., incoherently summed data). Pixels associated with lower spatial frequencies correspond to the background in the ultrasound image, while pixels associated with higher spatial frequencies correspond to edges (e.g., boundaries) in the ultrasound image. In some embodiments, the spatial frequency of a pixel is determined based on filters applied to the pixel data (e.g., high and / or low-pass filters), and / or other image processing techniques such as pixel-level analysis to assess whether there are color changes in the pixels (e.g., corresponding to the edges of an object). As described above, by weighting the first and second image data, speckles are smoothed away from the image background via incoherent joining of subframe data, and point spread at the boundaries of the captured object is minimized via coherent joining of subframe data (for example, the resolution of the captured object is improved).

[0084] With regard to weighting based on location (e.g., axial depth), pixels at relatively shallower depths (e.g., closer field) are weighted such that the second image data (e.g., incoherently summed acquired data) has a greater contribution to the image than the first image data (e.g., coherently summed image data), while pixels at relatively greater depths (e.g., farthest field) are weighted such that the first image data (e.g., coherently summed image data) has a greater contribution to the image than the second image data (e.g., incoherently summed data). In some cases, speckles are more pronounced in the near field of an ultrasound image (e.g., relatively shallower depth) and relatively less pronounced in the far field of the image (e.g., relatively greater depth). For example, ultrasound energy propagating through a medium (e.g., an anatomical object) has relatively high energy in the near field region of the medium, and this energy attenuates (e.g., decreases) as the ultrasound energy travels further (e.g., to the far field region of the medium). The higher the energy level, the more irregular the scattering becomes, so the near-field contains more speckle than the far-field. Furthermore, the resolution of the ultrasound image decreases as the depth of the image increases (for example, as the distance from the aperture used to acquire the ultrasound image increases). Therefore, the resolution of the far-field image is lower than the resolution of the near-field image. Thus, by weighting the first and second image data as described above, the speckle is smoothed out from the near-field image via incoherent coupling of subframe data, and the resolution of the object being imaged is improved in the far-field via coherent coupling of subframe data.

[0085] In some embodiments, the image generation module 1150 is implemented as a totalizer, such as a digital or analog totalizer. Additionally or alternatively, a processor circuit, such as the processor circuit 210 in Figure 2, implements the image generation module 1150. In some embodiments, for example, a GPU determines weights for the first and / or second image data, and then combines the weighted first and / or second image data to generate an image.

[0086] While the embodiments are illustrated and described herein, the signal path 1100 may include a particular set of components and / or be involved in a particular operation. For this purpose, additional components and / or operations may be included, and / or components and / or operations may be omitted. For example, the signal path 1100 may additionally or alternatively include an ADC (e.g., including analog-to-digital conversion), any suitable filters (e.g., low-pass filters, high-pass filters, and / or band-pass filters), etc. Furthermore, while certain components and / or operations of the signal path 1100 are shown copied across the first signal path 1102 and the second signal path 1104, it is understood that the first signal path 1102 and the second signal path 1104 may share one or more components and / or common operations. Instead of including the scan-transform module 640 and / or scan-transform module 930 in the first signal path 1102 and the scan-transform module 640 in the second signal path 1104, as in the example, a common scan-transform module is used before the buffer 1110 and / or on the output of the image generation module 1150. Furthermore, although the signal path 1100 is illustrated in a specific order, one or more of the components and / or operations may be performed in a different order or in parallel. In addition, the signal path 1100 may be used additionally or alternatively to coherently sum the first portion along the first signal path 1102 and incoherently sum the second portion of data corresponding to the set of subframes along the second signal path 1104, and the image generation module 1150 may generate an image based on the first and second portions.

[0087] Figure 12 is a block diagram of a signal path 1200 included in an ultrasound imaging system (e.g., ultrasound imaging system 100) and used to generate ultrasound image data and / or ultrasound images. In particular, the signal path 1200 is used to generate ultrasound images based on the coherent coupling of a first portion of a set of subframes and the incoherent coupling of a second portion of a set of subframes. The signal path 1200 is associated with a method or process for image generation. It will be understood that the elements of the signal path 1200 comprise computer program code or instructions executable by a processor circuit, such as the processor circuit 210 shown in Figure 2. For example, in some embodiments, the elements of the signal path 1200 comprise different processing (e.g., software) modules. In some embodiments, the elements of the signal path 1200 comprise different hardware components.

[0088] In some embodiments, the components and / or operations of the signal path 1200 are implemented by the probe 110 and / or host 130 shown in Figure 1. In particular, the components of the signal path 1200 are implemented by the beamformer 114, processor 116, communication interface 118, communication interface 136, and / or processor 134. In some embodiments, for example, the components of the signal path 1200 are distributed between the probe 110 and the host 130. Furthermore, the components of the signal path 1200 are implemented through a combination of hardware and software components and are executed by the processor circuit 210 described above with respect to Figure 2. For example, in some embodiments, one or more components and / or operations of the signal path 1200 can be executed by a GPU.

[0089] In some embodiments, ultrasonic data is received (e.g., input) to a signal path 1200. For example, the signal path 1200 receives data corresponding to a set of subframes based on received echoes associated with ultrasonic energy transmitted by an array of acoustic elements (e.g., transducer array 112). In particular, the data corresponding to a set of subframes is associated with echoes associated with ultrasonic energy transmitted by a set of subapers described herein and / or at different angle sets. The data corresponding to a set of subframes includes analog or digital data. For example, in some cases, the signal path 1200 receives raw analog electrical signals from the array of acoustic elements. In such cases, one or more operations of the signal path 1200 are performed on the analog signals. Additionally or alternatively, the signal path 1200 includes, or communicates with, an analog-to-digital converter (ADC), which samples the analog signals to supply digital subframe data.

[0090] As illustrated, the signal path 1200 includes a single processing path. In some embodiments, the signal path 1200 is implemented to coherently sum a first portion of data corresponding to a set of subframes and incoherently sum a second portion of data corresponding to a set of subframes. As described herein, the first portion of data corresponding to a set of subframes and the second portion of data corresponding to a set of subframes correspond to a first subset and a second subset of the set of subframes, respectively. Additionally or alternatively, the first portion of data corresponding to a set of subframes and the second portion of data corresponding to a set of subframes correspond to a first region (e.g., a pixel region) and a second region of the set of subframes, respectively. For example, the first and second regions correspond to groups of pixels, such as pixels contained in the top or bottom half of a subframe, or pixels having certain characteristics (e.g., location, and / or spatial frequency).

[0091] One or more components and / or operations associated with the signal path 1200 are applicable to a first portion of data corresponding to a set of subframes, a second portion of data corresponding to a set of subframes, or both. For example, the signal path 1200 includes a coherent portion 1202, which includes components and operations associated with the coherent coupling of the first portion of data corresponding to a set of subframes, as illustrated, and an incoherent portion 1204, which includes components and operations associated with the incoherent coupling of the second portion of data corresponding to a set of subframes. The signal path 1200 also includes components and / or operations associated with both the first and second portions of data corresponding to a set of subframes, such as a beamformer 610, an envelope detection module 620, a log compression module 630, and a scan transformation module 640. More specifically, the components of the coherent portion 1202 are configured to perform operations on a first portion of the data corresponding to a set of subframes and not on a second portion of the data corresponding to a set of subframes; the components of the incoherent portion 1204 are configured to perform operations on a second portion of the data corresponding to a set of subframes and not on a first portion of the data corresponding to a set of subframes; and the remaining components of the signal path 1200 are configured to perform operations on both the first and second portions of the data corresponding to a set of subframes.

[0092] As illustrated, after the data corresponding to a set of subframes (e.g., both the first and second parts of the data) is beamformed by the beamformer 610 as described above with reference to Figures 6 and 9, the first part of the data corresponding to the set of subframes is coherently coupled via the coherent portion 1202 of the signal path 1200. In particular, the first part of the data corresponding to a set of subframes is coherently coupled via the coherent coupling module 920, and in preparation for coherent coupling, the first part of the data corresponding to a set of subframes is scanned-converted and / or corrected for alignment errors (e.g., sway) via the scan-converting module 640 and / or alignment module 910, respectively, as described with reference to Figure 9.

[0093] In some embodiments, envelope detection is performed in the envelope detection module 620 on a second portion of the data corresponding to a set of subframes and on a first portion of the data that is coherently coupled to the set of subframes. Similarly, log compression is performed on each of these datasets in the log compression module 630. Subsequently, scan transformation is performed in the scan transformation module 640 on the second portion of the data corresponding to the set of subframes and optionally on the first portion of the data that is coherently coupled to the set of subframes.

[0094] In the incoherent portion 1204 of the signal path 1200, a second portion of the data corresponding to a set of subframes is incoherently coupled via an incoherent coupling module 650. Using the incoherently coupled second portion of the data corresponding to the set of subframes and the coherently coupled first portion of the data corresponding to the set of subframes, the image generation module 1210 generates a synthesized ultrasound image. In some embodiments, for example, the image generation module 1210 generates an image by summing and / or combining the incoherently coupled second portion of the data corresponding to the set of subframes and the coherently coupled first portion of the data corresponding to the set of subframes into a single dataset.

[0095] Figure 13 shows an exemplary ultrasound image 1300 (e.g., a B-mode ultrasound image) generated based on both coherent and incoherent coupling of data corresponding to a set of subframes, using the techniques described herein with respect to Figures 4, 5A, 5B, 6, 8, 9, 11, and 12. In particular, the ultrasound image 1300 is generated by mixing (e.g., combining) coherently coupled and incoherently coupled image data acquired using one or more subapers and / or beam steering angles. For this purpose, the ultrasound image 1300 is produced by the signal path 1100 in Figure 11 and / or the signal path 1200 in Figure 12. As further shown, the ultrasound image 1300 is shown with respect to an axial distance representing the distance from the transducer array (e.g., depth) and a lateral distance corresponding to the position along the transducer array (e.g., the position of the acoustic elements in the transducer array), with the axial distance shown in centimeters (cm). The intensity of the ultrasound imaging data (e.g., the received echo) is further indicated in decibels (dB) using a color-coded scale 1302.

[0096] Compared to ultrasound image 300 in Figure 3, both speckles present in ultrasound image 1300 are reduced, and the resolution of ultrasound image 1300 is improved. In particular, region 1310 of ultrasound image 1300 (e.g., near-field region) is less distorted than region 310 of ultrasound image 300, and region 1320 of ultrasound image 1300 (e.g., far-field region) is more resolved. These improvements in image quality are brought about, for example, by incoherent coupling of data corresponding to region 1310 and coherent coupling of data corresponding to region 1320. Additionally or alternatively, improvements are brought about, for example, by greater weighting of incoherent coupling of data associated with region 1310 and / or the background of image 1300, and by greater weighting of coherent coupling of data associated with region 1320 and / or edges contained in image 1300. As shown in the example, the ultrasound image 700 in Figure 7 and the ultrasound image 1000 in Figure 10 are combined to generate the ultrasound image 1300. That is, for example, the speckle reduction produced by the generation of ultrasound image 700 (e.g., via incoherent coupling) is combined with the resolution improvement affected by the generation of ultrasound image 1000 (e.g., via coherent coupling) to generate the ultrasound image 1300.

[0097] Returning to Figure 8, step 810 includes outputting the image generated in step 808 for display. For example, the image is output to a display that communicates with the host 130, such as display 132. Since the image is generated in step 808 based on coherent coupling, or a weighting between coherent and incoherent coupling, outputting the image includes outputting an image having the features described above with reference to Figures 7, 10, and / or 13. That is, for example, step 810 includes outputting an ultrasound image synthesized based on coherent coupling, incoherent coupling, or both.

[0098] Those skilled in the art will recognize that the apparatus, systems, and methods described above can be modified in various ways. Accordingly, those skilled in the art will understand that the embodiments contained herein are not limited to the specific exemplary embodiments described above. While exemplary embodiments have been shown and described, a wide range of modifications, alterations, and substitutions are contemplated in the foregoing disclosure. Such modifications will be understood to be made to the foregoing without departing from the scope of the foregoing disclosure. Accordingly, the appended claims should be interpreted broadly and in a manner consistent with the foregoing disclosure.

Claims

1. An array of acoustic elements that transmit ultrasonic energy and receive echoes associated with the ultrasonic energy, An ultrasonic imaging system comprising an array of acoustic elements and a processor circuit that communicates with the array of acoustic elements, The ultrasonic energy comprises a first ultrasonic energy and a second ultrasonic energy, The aforementioned processor circuit Transmitting the first ultrasonic energy using a first subset of the array of acoustic elements, Transmitting the second ultrasonic energy using a second subset of the array of acoustic elements, Receiving data corresponding to a set of subframes based on the received echo, wherein the set of subframes includes a first subframe and a second subframe. Coherently coupling data corresponding to a first portion of the first subframe and data corresponding to a first portion of the second subframe, wherein the first portion of the first subframe and the first portion of the second subframe are portions corresponding to the first ultrasonic energy, and the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe include phase information, A first image is generated based on the coherent coupling of the first portion of the first subframe and the first portion of the second subframe, A second image is generated based on an incoherent coupling of the first portion of the first subframe and the first portion of the second subframe, The first image and the second image are combined by weighted synthesis, The combined image is output to a display that communicates with the processor circuit. The weighting is determined based on the spatial frequencies of the pixels in the first portion of the first subframe, such that pixels associated with relatively lower spatial frequencies are weighted such that the second image has a greater contribution to the combined image than the first image, and pixels associated with relatively higher spatial frequencies are weighted such that the first image has a greater contribution to the combined image than the second image, or An ultrasonic imaging system in which the weighting is determined based on the depth of pixels in a first portion of the first subframe, wherein pixels at relatively shallower depths are weighted such that the second image makes a greater contribution to the combined image than the first image, and pixels at relatively greater depths are weighted such that the first image makes a greater contribution to the combined image than the second image.

2. The ultrasonic imaging system according to claim 1, wherein the first subframe corresponds to the received echo associated with the first ultrasonic energy, and the second subframe corresponds to the received echo associated with the second ultrasonic energy.

3. In order to receive the echo associated with the ultrasonic energy, the array of acoustic elements Using the first subset of the array of acoustic elements, to receive echoes associated with the first ultrasonic energy, The ultrasonic imaging system according to claim 1, further comprising using the second subset of the array of acoustic elements to receive echoes associated with the second ultrasonic energy.

4. The ultrasonic imaging system according to claim 1, wherein the processor circuit generates the image based on the detection of the envelope of the coherent coupling.

5. The ultrasonic imaging system according to claim 1, wherein the processor circuit generates the image based on the coherent coupling log compression.

6. The aforementioned processor circuit A scan transformation is performed on the data corresponding to the set of subframes. The ultrasonic imaging system according to claim 1, wherein the processor circuit further coherently combines the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe based on the scan conversion.

7. Incoherently coupling data corresponding to the second portion of the first subframe and data corresponding to the second portion of the second subframe, wherein the second portion of the first subframe and the second portion of the second subframe are the portions corresponding to the second ultrasonic energy, The ultrasonic imaging system according to claim 1, further comprising generating the image based on the incoherent coupling of the second portion of the first subframe and the second portion of the second subframe.

8. The aforementioned processor circuit Align the first portion of the first subframe with the first portion of the second subframe, The ultrasonic imaging system according to claim 1, wherein the processor circuit coherently couples the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe, further based on the alignment.

9. The aforementioned processor circuit Identifying the difference between the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the third subframe of the set of subframes, wherein the first subframe and the third subframe are sequentially acquired subframes collected using the same sub-aperture and beam steering angle. The ultrasonic imaging system according to claim 8, wherein the first portion of the first subframe is aligned with the first portion of the second subframe, based on adjusting the data corresponding to the first portion of the first subframe based on the identified difference.

10. The ultrasonic imaging system according to claim 1, wherein the processor circuit comprises a graphics processing unit.

11. The steps of transmitting ultrasonic energy, wherein the ultrasonic energy comprises a first ultrasonic energy and a second ultrasonic energy, and to receive echoes associated with the ultrasonic energy, the processor circuit controls an array of acoustic elements that communicate with the processor circuit, transmitting the first ultrasonic energy using a first subset of the array of acoustic elements and transmitting the second ultrasonic energy using a second subset of the array of acoustic elements, The steps of receiving data corresponding to a set of subframes by the processor circuit based on the received echo, wherein the set of subframes comprises a first subframe and a second subframe, A step of coherently coupling data corresponding to a first portion of the first subframe and data corresponding to a first portion of the second subframe using the processor circuit, wherein the first portion of the first subframe and the first portion of the second subframe are portions corresponding to the first ultrasonic energy, and the data corresponding to the first portion of the first subframe and the data corresponding to the first portion of the second subframe include phase information. The processor circuit generates a first image based on the coherent coupling of the first portion of the first subframe and the first portion of the second subframe. The processor circuit generates a second image based on an incoherent coupling between the first portion of the first subframe and the first portion of the second subframe. The processor circuit performs the steps of combining the first image and the second image by weighted synthesis, The process includes the step of outputting the combined image to a display that communicates with the processor circuit using the processor circuit, The weighting is determined based on the spatial frequencies of the pixels in the first portion of the first subframe, such that pixels associated with relatively lower spatial frequencies are weighted such that the second image has a greater contribution to the combined image than the first image, and pixels associated with relatively higher spatial frequencies are weighted such that the first image has a greater contribution to the combined image than the second image, or The weighting is determined based on the depth of pixels in a first portion of the first subframe, wherein pixels at a relatively shallower depth are weighted such that the second image has a greater contribution to the combined image than the first image, and pixels at a relatively greater depth are weighted such that the first image has a greater contribution to the combined image than the second image.

Images