Ultrasound imaging system including configurable transducer probe

Abstract

A system and method for controlling an ultrasound probe having a transducer array of transducer elements is provided. The method comprises: receiving, at a transducer element, an echo signal reflected in a near field and / or a far field of a medium, and outputting an electrical echo signal; digitizing the electrical echo signal; multiplexing the digitized echo signal to output a first set of digitized echo signals corresponding to a first set of transducer elements of the plurality of transducer elements, the first set of transducer elements defining a small aperture for receiving echo signals reflected in the near field; grouping the transducer elements in the second set of transducer elements into sub-arrays, thereby providing a second set of digitized echo signals; adding together digitized echo signals from a second set of transducer elements within each sub-array, each sub-array for receiving echo signals reflected in the far field, where the second set of transducer elements includes more transducer elements than the first set of transducer elements; and outputting an echo data stream comprising the first set of digitized echo signals and / or the second set of digitized echo signals to a host system via a communication interface having a fixed maximum bandwidth.

Description

Background Art

[0001] Ultrasound imaging has become indispensable for many medical imaging applications. An ultrasound imaging system typically includes an ultrasound probe and a processing system. The probe may include an array of ultrasound transducer elements configured to transmit sound waves through the patient's body and receive echo signals when the sound waves reflect from tissues, organs, and other structures. The timing and intensity of the echo signals typically correspond to the size, shape, and mass of structures in the patient's body, an image of which is displayed to a user of the ultrasound imaging system.

[0002] Modern ultrasound imaging systems may include digital probes that digitize the echo signals from the transducer elements within the probe itself. Since no analog processing channels are required in the base system connected to the digital probe, image quality is not constrained by the ultrasound imaging system. However, digital probes have a fixed digital bandwidth that limits the performance of the ultrasound imaging system. That is, the maximum data rate achievable in a digital probe is limited by power (heat), transistor technology speed (which is a trade-off between cost and reliability), and the number of lines in the cable assembly that connects the digital probe to the host system. When these metrics are defined by project requirements, various methods must be used to reduce the resulting data rate to accommodate the desired number of channels or dynamic range.

[0003] What is needed is an ultrasound imaging system with a digital probe that effectively reduces the data rate of the received echo signals, thereby effectively increasing the bandwidth. Reducing the data rate will allow more channels to be recorded without affecting the final image quality while avoiding the use of more power, implementation of faster / more expensive technology, and / or adding more conductors.

[0004] WO2022 / 069264A1 describes an ultrasound imaging system including an ultrasound probe. The ultrasound probe includes a housing and a transducer array having first, second and third acoustic elements.

[0005] US 2008 / 114248 A1 describes a method for ultrasonic interrogation of a medium, comprising transmitting non-beamformed or beamformed ultrasonic waves into the medium. Summary of the invention

[0006] According to a representative embodiment, a transducer probe of an ultrasound imaging system includes a transducer array, a plurality of analog-to-digital converters (ADCs), a combiner, a switch, a digital processing unit, and a communication interface. The transducer array includes a plurality of transducer elements, which are configured to: transmit an ultrasound signal into a medium, receive an echo signal in response to the ultrasound signal being reflected in the near field and the far field of the medium, and output a corresponding electrical echo signal. The ADC is configured to digitize the electrical echo signal to provide a digitized echo signal. The combiner includes a multiplexer and a beamformer. The multiplexer is configured to multiplex the digitized echo signal to output a first group of digitized echo signals, the first group of digitized echo signals corresponding to a first group of transducer elements among a plurality of transducer elements, the first group of transducer elements defining a small aperture for receiving echo signals reflected in the near field. The beamformer includes a plurality of adders configured to group the transducer elements in the second group of transducer elements into subarrays providing a second group of digitized echo signals, and add together the digitized echo signals from the second group of transducer elements within each subarray, each subarray being used to receive echo signals reflected in the far field, wherein the second group of transducer elements includes more transducer elements than the first group of transducer elements. The switch is operable to select a multiplexer for near-field ultrasound imaging and a beamformer for far-field ultrasound imaging. The digital processing unit is configured to receive the first group of digitized echo signals and the second group of digitized echo signals, and output corresponding digital echo streams. The communication interface is configured to transmit the echo data stream to an ultrasound imaging system host, wherein the communication interface has a fixed maximum bandwidth. The small aperture defined by the first group of transducer elements provides a digital bandwidth of the echo data stream that is less than the maximum bandwidth of the communication interface.

[0007] In some embodiments, the combiner may further include a sampling rate switch configured to selectively connect the plurality of ADCs to a first signal generator or a second signal generator, wherein the first signal generator is configured to: provide a first signal, the first signal controlling the plurality of ADCs to sample the electrical echo signals at a first sampling rate for near-field imaging; and provide a second signal, the second signal controlling the plurality of ADCs to sample the electrical echo signals at a second sampling rate for far-field imaging, and wherein the first sampling rate is greater than the second sampling rate.

[0008] According to another representative embodiment, a method for controlling an ultrasound transducer probe including a transducer array having a plurality of transducer elements is provided. The method includes: receiving echo signals at a plurality of transducer elements in response to ultrasound signals emitted by at least some of the plurality of transducer elements, wherein the echo signals are reflected in the near field and the far field of the medium; and outputting corresponding electrical echo signals; digitizing the electrical echo signals to provide digitized echo signals; multiplexing the digitized echo signals to output a first group of digitized echo signals, the first group of digitized echo signals corresponding to a first group of transducer elements among the plurality of transducer elements, the first group of transducer elements defining a small aperture for receiving echo signals reflected in the near field; multiplexing the electrical echo signals to provide digitized echo signals; and outputting a first group of digitized echo signals corresponding to a second group of transducer elements. The transducer elements are grouped into subarrays that provide a second set of digitized echo signals; the digitized echo signals from the second set of transducer elements within each subarray are added together, each subarray being used to receive echo signals reflected in a far field, wherein the second set of transducer elements includes more transducer elements than the first set of transducer elements; and an echo data stream including the first set of digitized echo signals and the second set of digitized echo signals is output to a host system via a communication interface having a fixed maximum bandwidth, wherein the small aperture defined by the first set of transducer elements provides a digital bandwidth of the echo data stream that is less than the maximum bandwidth of the communication interface.

[0009] According to another aspect of the present invention, a transducer probe of an ultrasound imaging system includes a transducer array, a plurality of analog-to-digital converters (ADCs), a combiner, a digital processing unit, and a communication interface. The transducer array includes a plurality of transducer elements, which are configured to: transmit an ultrasound signal into a medium, receive an echo signal in response to the ultrasound signal being reflected in the near field and / or far field of the medium, and output a corresponding electrical echo signal. The ADC is configured to digitize the electrical echo signal to provide a digitized echo signal. The combiner is configured to process a first group of digitized echo signals corresponding to a first group of transducer elements in a plurality of transducer elements differently from a second group of digitized echo signals corresponding to a second group of transducer elements in a plurality of transducer elements, wherein the first group of transducer elements includes fewer transducer elements than the plurality of transducer elements for receiving echo signals reflected in the near field, thereby defining a small aperture, and wherein the second group of transducer elements includes more transducer elements than the first group of transducer elements for receiving echo signals reflected in the far field, thereby defining a large aperture. The digital processing unit is configured to receive the first group of digitized echo signals and / or the second group of digitized echo signals and output a corresponding digital echo stream. The communication interface is configured to transmit the echo data stream to the ultrasound imaging system host, wherein the communication interface has a fixed maximum bandwidth. The small aperture defined by the first group of transducer elements provides a digital bandwidth of the echo data stream that is less than the maximum bandwidth of the communication interface.

[0010] In some embodiments, the combiner may include a multiplexer configured to multiplex the digitized echo signals to output a first group of digitized echo signals corresponding to a first group of transducer elements defining a small aperture.

[0011] In some embodiments, the electrical echo signals may be digitized at a first sampling rate to provide a first set of digitized echo signals, and the electrical echo signals may be digitized at a second sampling rate to provide a second set of digitized echo signals, wherein the first sampling rate is different from the second sampling rate, wherein, preferably, the first sampling rate is at least 25% greater than the second sampling rate.

[0012] In some embodiments, the combiner may include a plurality of adders configured to group the transducer elements in the second set of transducer elements into sub-arrays and to add together the digitized echo signals from the transducer elements within each sub-array.

[0013] In some embodiments, each sub-array may include two of the transducer elements in the second group of transducer elements.

[0014] In some embodiments, the combiner may further include a plurality of delay elements disposed before the plurality of adders and configured to delay the digitized echo signals by corresponding delay amounts so as to focus the digitized echo signals at corresponding pixels being imaged.

[0015] According to another aspect of the present invention, a method for controlling an ultrasonic transducer probe is provided, the ultrasonic transducer probe comprising a transducer array having a plurality of transducer elements. The method comprises: receiving echo signals at a plurality of transducer elements in response to ultrasonic signals emitted by at least some of the plurality of transducer elements, wherein the echo signals are reflected in the near field and / or far field of the medium, and outputting corresponding electrical echo signals; digitizing the electrical echo signals to provide digitized echo signals; selecting a first group of digitized echo signals corresponding to a first group of transducer elements of the plurality of transducer elements, wherein the first group of transducer elements comprises fewer transducer elements than the plurality of transducer elements for receiving the echo signals reflected in the near field, thereby defining a small aperture; selecting a second group of digitized echo signals corresponding to a second group of transducer elements among the plurality of transducer elements, wherein the second group of transducer elements includes more transducer elements than the first group of transducer elements for receiving the echo signals reflected in the far field, thereby defining a large aperture; and outputting an echo data stream including the first group and / or the second group of digitized echo signals to a host system via a communication interface having a fixed maximum bandwidth, wherein the small aperture defined by the first group of transducer elements provides a digital bandwidth of the echo data stream that is less than the maximum bandwidth of the communication interface.

[0016] In some embodiments, the electrical echo signals may be digitized at a first sampling rate to provide a first set of digitized echo signals, and the electrical echo signals may be digitized at a second sampling rate to provide a second set of digitized echo signals, wherein the first sampling rate is different from the second sampling rate, wherein, preferably, the first sampling rate is at least 25% greater than the second sampling rate.

[0017] In some embodiments, selecting the first set of digitized echo signals may include multiplexing the digitized echo signals to output a first set of digitized echo signals corresponding to the first set of transducer elements.

[0018] In some embodiments, selecting the second set of digitized echo signals includes: grouping transducer elements in the second set of transducer elements into subarrays; and summing digitized echo signals from transducer elements within each subarray to reduce a digital bandwidth of the second set of digitized echo signals.

[0019] In some embodiments, each sub-array may include two of the transducer elements in the second group of transducer elements.

[0020] In some embodiments, selecting the first set of digitized echo signals may further include delaying the digitized echo signals by a corresponding delay amount before summing the digitized echo signals from the transducer elements within each subarray so as to focus the digitized echo signals at corresponding pixels being imaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Representative embodiments are best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that the various features are not necessarily drawn to scale. In fact, for clarity of discussion, the dimensions may be increased or decreased arbitrarily. Where applicable and practical, similar reference numerals refer to similar elements.

[0022] Figure 1 is a simplified schematic diagram of an ultrasound imaging system including an ultrasound probe and a host according to a representative embodiment.

[0023] Figure 2 is a simplified schematic diagram of illustrative processor circuitry implemented by an ultrasound imaging system in accordance with a representative embodiment.

[0024] Figure 3 is a schematic diagram showing illustrative circuitry for an ultrasound imaging system having a transducer array in accordance with a representative embodiment.

[0025] Figure 4 is a simplified block diagram of a transducer probe for use in an ultrasound imaging system using a multiplexer to reduce digital bandwidth in accordance with a representative embodiment.

[0026] Figure 5 is a simplified block diagram of a transducer probe for use in an ultrasound imaging system using a beamformer to reduce digital bandwidth according to another representative embodiment.

[0027] Figure 6 is a simplified block diagram of a switching circuit for a transducer probe in an ultrasound imaging system for reducing digital bandwidth according to another representative embodiment.

[0028] Figure 7 is a flow chart of a method for controlling an ultrasound transducer probe including a transducer array having a plurality of transducer elements, according to a representative embodiment. DETAILED DESCRIPTION

[0029] In the following detailed description, for the purpose of explanation rather than limitation, representative embodiments of the disclosure of specific details are set forth to provide a thorough understanding of the embodiments according to the present teachings. The description of known systems, equipment, materials, operating methods, and manufacturing methods may be omitted to avoid blurring the description of the representative embodiments. Nevertheless, systems, equipment, materials, and methods within the knowledge of those of ordinary skill in the art are within the scope of the present teachings and may be used according to the representative embodiments. It should be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not intended to be limited. The defined terms are terms other than the technical and scientific meanings of the defined terms that are generally understood and accepted in the technical field of the present teachings.

[0030] It should be understood that although the terms first, second, third, etc. may be used to describe various elements or components in this article, these elements or components should not be limited by these terms. These terms are only used to distinguish one element or component from another element or component. Therefore, without departing from the teachings of the present invention, the first element or component discussed below may be referred to as the second element or component.

[0031] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to be limiting. As used in the specification and the appended claims, the singular terms "a", "an", and "the" are intended to include both singular and plural forms, unless the context clearly dictates otherwise. In addition, the terms "include", "comprises", and / or similar terms specify the presence of the features, elements, and / or parts, but do not exclude the presence or addition of one or more other features, elements, parts, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more associated listed items.

[0032] As used in the specification and the appended claims, and in addition to its ordinary meaning, the term "about" means having an acceptable limit or degree. For example, "about 20 GHz" means that a person of ordinary skill in the art would consider the signal to be 20 GHz within reasonable measure.

[0033] As used in the specification and appended claims, in addition to its ordinary meaning, the term "substantially" means within acceptable limits or degrees. For example, "plurality of transducer ports are substantially the same" means that a person of ordinary skill in the art would consider the plurality of transducer ports to be the same.

[0034] Figure 1is a simplified schematic diagram of an ultrasound imaging system including an ultrasound probe and a host according to a representative embodiment. The system is used to scan an area, zone, or volume of a patient's body. Portions of the system are described in U.S. Patent Application Publication US2021 / 0007717, filed on January 31, 2019, entitled “DIGITAL ULTRASOUND CABLE AND ASSOCIATED DEVICES, SYSTEMS, AND METHODS,” the entire contents of which are incorporated herein by reference.

[0035] refer to Figure 1 , the ultrasound imaging system 100 includes a digital ultrasound probe 110 that communicates with an ultrasound host system 130 via a communication link 150. At a high level, the probe 110 transmits ultrasound waves toward an object 105 (e.g., a patient's body or anatomical structure) and receives ultrasound echoes reflected from the object 105. The probe 110 digitizes the electrical echo signals representing the received echoes and sends the digitized signals as a digital echo data stream to the host system 130 via the communication link 150 for processing and image display. The communication link 150 can transmit data in an analog format, a digital format, and / or both an analog and digital format. The probe 110 can be any suitable form for imaging various body parts of a patient when positioned inside or outside the patient's body. For example, the probe 110 can be in the form of a handheld ultrasound scanner, such as a transthoracic echocardiogram (TTE) probe or a patch-based ultrasound device. In some embodiments, the probe 110 is not handheld, but is held in place via a strap, a mechanical retainer, and / or an adhesive. In some embodiments, the probe 110 may be a catheter, a transesophageal echocardiogram (TEE) probe, or other intraluminal or intraluminal probe. The probe 110 may include Figure 1 Any of the components shown. Any of the components of the probe 110 may be positioned or stored in the housing 111. When the probe 110 is a handheld probe, the housing 111 is configured to be grasped by the hand of a user (eg, a sonographer).

[0036] In the depicted configuration, the probe 110 includes a transducer array 112, circuitry 114, and a communication interface 140 within a housing 111. The transducer array 112 transmits ultrasound signals (waves) toward the object 105, and receives echo signals (waves) reflected from the interior of the object 105 back to the transducer array 112. The transducer array 112 may include an array of acoustic elements. The transducer array 112 may be coupled to a microbeam former (not shown) and control the reception of signals by the acoustic elements. In an exemplary embodiment, the transducer array 112 is a 1X-dimensional array, such as a 1.25D array or a 1.5D array. In other embodiments, the transducer array may be arranged as a one-dimensional (1D) array or a two-dimensional (2D) array.

[0037] The acoustic element may be referred to as a transducer element, as described below, and may be a capacitive micromachined ultrasonic transducer (CMUT) or a piezoelectric transducer formed of a material such as PZT or PVDF. Each transducer element may transmit an ultrasonic signal into the object 105, and may receive an echo signal when the ultrasonic signal is reflected from within the object 105. Each transducer element generates an analog electrical signal representing the received ultrasonic echo signal. The transducer array 112 may include M transducer elements arranged in (one or more) rows and (one or more) columns, thereby generating M analog ultrasonic echo signals.

[0038] The circuit 114 positioned within the probe 110 can be any suitable type of circuit and can serve a number of functions. For example, the circuit 114 may include resistors, capacitors, transistors, inductors, relays, clocks, timers, or any other suitable electrical components that can be integrated into an integrated circuit. In addition, the circuit 114 can be configured to support analog signals and / or digital signals transmitted to or from the transducer array 112 and / or the probe 110. In some embodiments, the circuit 114 may include an analog front end (AFE), an analog-to-digital converter (ADC), a multiplexer (MUX), and an encoder, as well as various other components. In some embodiments, the circuit 114 may include hardware components, software components, and / or a combination of hardware components and software components. Refer to the following Figure 4 and Figure 5 Examples of circuit 114 are discussed.

[0039] The communication interface 122 is coupled to the circuit 114 via L signal lines. In some embodiments, the circuit 114 can reduce the number of required lines from M signal lines to L signal lines. This can be achieved by any suitable method using any suitable components. For example, a MUX, beamformer, or other component can be used to reduce the M signal lines from the transducer array 112 to L signal lines 166, as described below. Figure 1 In an embodiment of the present invention, L is less than M. The communication interface 122 is configured to transmit the L signals to the host system 130 via the communication link 150. In an embodiment, the communication interface 122 and / or the communication link 150 has a fixed maximum bandwidth. The communication interface 122 may include a combination of hardware components and software components configured to generate a signal 168 that carries information from the L signals transmitted on the communication link 150. In an exemplary embodiment, the signal 168 is a digital signal such that digital ultrasound data is transmitted from the probe 110 to the host system 130, as described below. The communication link 150 may include L data channels for transmitting the signal 168 to the host system 130.

[0040] The host system 130 can be any suitable computing and display device, such as a workstation, a personal computer (PC), a laptop computer, a tablet computer, a mobile phone, or a patient monitor. In some embodiments, the host system 130 can be located on a movable cart. The host system 130 includes a communication interface 140 configured to receive a signal 168 from the communication link 150. The communication interface 140 can include a hardware component, a software component, or a combination of a hardware component and a software component. The communication interface can be substantially similar to the communication interface 122 in the probe 110.

[0041] The circuit 134 positioned within the host system 130 can be of any suitable type and can serve any suitable function. For example, the circuit 134 can include resistors, capacitors, transistors, inductors, relays, clocks, timers, processing components, memory components, or any other suitable electrical components that can be integrated into an integrated circuit. In addition, the circuit 134 can be configured to support analog signals and / or digital signals transmitted to or from the probe 110. The circuit 134 can be configured to process the digital signal 168 received from the probe 110. For example, the circuit 134 can expand the L signal lines received from the probe 110 to the original M signal lines corresponding to a specific transducer element or group or tile of transducer elements within the transducer array 112. The circuit 134 can be configured to generate an image signal 174 for display to a user and / or perform image processing and image analysis for various diagnostic modalities or ultrasound types (B-mode, CW Doppler, etc.). The circuit 134 can additionally include the following references Figure 2 The one or more processing circuits discussed. For example, the circuit 134 may include a general purpose computer, a computer processor, a microprocessor, a graphics processing unit (GPU), a central processing unit (CPU), a digital signal processor (DSP), a microcontroller, a state machine, a programmable logic device, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on a chip (SOC), or a combination thereof. The circuit 134 may be configured to generate an image signal 174 for display to a user and / or perform image processing and image analysis for various diagnostic modalities.

[0042] The display 132 is coupled to the circuit 134. For example, the display 132 may include a monitor, a touch screen, a television, a liquid crystal display (LCD), a light emitting diode (LED) display, a flat panel display, a solid state display, a cathode ray tube (CRT) display, or any suitable display. The display 132 is configured to display images and / or diagnostic results processed by the circuit 134.

[0043] The host system 130 may also include a user interface (not shown) for providing information and data output by the circuit 134 to a user and / or for receiving information and data input by a user. For example, the user interface may include a mouse, keyboard, mouse, trackball, joystick, microphone, camera, touch pad, touch screen, voice or gesture recognition captured by a microphone or camera. All or part of the interface may be combined with the display 132 as a graphical user interface (GUI) for displaying information to a user and receiving information from a user.

[0044] Although the present invention is described in the context of transmitting detected ultrasound echo signal data from the probe 110 to the host system 130 for display, Figure 1 , but the host system 130 may also generate and transmit control signals for controlling the operation of the probe 110 (eg, the excitation of transducer elements at the transducer array 112 ).

[0045] Figure 2 is a simplified schematic diagram of processor circuitry implemented by ultrasound imaging system 100 according to a representative embodiment.

[0046] For example, the processor circuit 210 may be configured to Figure 1 The processor circuit 210 may be implemented in the host system 130 and / or any other suitable location of the ultrasound imaging system 100. The one or more processor circuits 210 may be configured to perform the operations described herein. The processor circuit 210 may be part of the circuit 114 and / or the circuit 134, or may be a separate circuit. In an example, the processor circuit 210 may communicate with the transducer array 112, the circuit 114, the communication interface 122, the communication interface 140, the circuit 134, and / or the display 132, as well as any other suitable components or circuits within the ultrasound imaging system 100.

[0047] refer to Figure 2 , the processor circuit 210 includes a processor 260, a memory 264, and a communication module 268. These elements may communicate with each other directly or indirectly (eg, via one or more buses).

[0048] Processor 260 may be implemented by a general purpose computer, computer processor, microprocessor, GPU, CPU, DSP, microcontroller, state machine, programmable logic device, FPGA, ASIC, SOC, or a combination thereof using any combination of hardware, software, firmware, hardwired logic circuits, or a combination thereof. In addition, any processing unit or processor herein may include multiple processors, parallel processors, or both. Multiple processors may be included in a single device or multiple devices or coupled to a single device or multiple devices.

[0049] As used herein, the term "processor" encompasses an electronic component capable of executing a program or machine-executable instructions. References to a computing device that includes a "processor" should be interpreted as including more than one processor or processing core, such as in a multi-core processor. A processor may also refer to a collection of processors within a single computer system or distributed among multiple computer systems, such as in a cloud-based or other multi-site application. The term computing device should also be interpreted to include a collection or network of computing devices, each of which includes one or more processors. A program has software instructions that are executed by one or more processors, which may be within the same computing device or may be distributed across multiple computing devices.

[0050] The memory 264 stores instructions that can be executed by the processor 260. The memory 264 may include main memory and / or static memory, wherein such memories may communicate with each other and with the processor 260 via one or more buses. The memory 264 stores instructions for implementing some or all aspects of the methods and processes described herein. The memory 264 may include cache memory (e.g., cache memory of the 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 a combination of different types of memory.

[0051] The memory 264 includes a non-transient computer-readable medium storing instructions 266. The instructions 266 may include instructions that, when executed by the processor 260, cause the processor 260 to perform the operations described herein with reference to the probe 110 and / or the host system 130. The instructions 266 may also be referred to as code. The terms "instructions" and "code" should be broadly interpreted to include any type of (one or more) computer-readable statements. For example, the terms "instructions" and "code" may refer to one or more programs, routines, subroutines, functions, processes, etc. "Instructions" and "code" may include a single computer-readable statement or many computer-readable statements. As used herein, the term "non-transient" should not be interpreted as a permanent characteristic of a state, but rather a characteristic of a state that will last for a period of time. The term "non-transient" specifically negates transient characteristics, such as characteristics of a carrier or signal or other forms that exist only temporarily anywhere at any time. The memory 264 may be secure and / or encrypted, or unsecure and / or unencrypted.

[0052] The communication module 268 may include any electronic circuitry and / or logic circuitry to facilitate direct or indirect communication of data 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 instances, the communication module 268 facilitates direct or indirect communication between various elements of the processor circuit 210 and / or the probe 110 and / or the host system 130.

[0053] Figure 3 is a schematic diagram showing illustrative circuitry of an ultrasound imaging system 100 having a transducer array according to a representative embodiment. Specifically, Figure 3 A more detailed view of circuitry within probe 110 connected to host system 130 is provided according to a representative embodiment. Any of the components of probe 110 may be positioned or arranged in a housing (eg, housing 111).

[0054] refer to Figure 3 , the circuit of the probe 110 includes a transducer array 312, which can be substantially the same as the transducer array 112 discussed above. The transducer array 312 communicates with the analog front end (AFE) circuit 310 and the digitizing circuit 320 via corresponding conductors. The conductors can include conductive paths or conductive traces positioned on a printed circuit board (PCB), a flexible or non-flexible substrate, or in any other suitable configuration. Axes 398 and 399 provide orientation directions of the transducer array 312, wherein axis 398 illustrates an elevation or elevation direction, and axis 399 illustrates an azimuth or lateral direction. For ease of explanation, it is assumed that the transducer array 312 is a 1.0-dimensional (D) array with a single row of N transducer elements in the azimuth direction, as described below. Without departing from the scope of the present teachings, any suitable number N of transducer elements may be included. For example, the row of N transducer elements includes 2, 8, 16, 50, 64, 80, 90, 100, etc. transducer elements. The N transducer elements have N associated channels (signal paths) for conveying analog and digital signals.

[0055] The transmitting portion of the transducer element is configured to transmit an ultrasonic signal into a medium (e.g., object 105). The receiving portion of the N transducer elements is configured to receive an ultrasonic echo signal in response to the transmitted ultrasonic signal being reflected from the medium, and output a corresponding electrical echo signal. Each of the transmitting portion and the receiving portion may include one or more of the transducer elements of the transducer array 312 (up to and including all N transducer elements), and may include the same or different transducers to provide unique benefits for any particular situation or to meet application-specific design requirements of various embodiments, as will be apparent to those skilled in the art.

[0056] In various embodiments, the transducer array 312 is a suitable type of 1.XD array, such as a 1.25D array, a 1.5D array, or a 1.75D array or, for example, a 2.XD array. In some aspects, the 1.25D array may include circuitry for controlling the aperture size in elevation. The 1.5D array may include additional circuitry configured to apply various delays to received signals from elements in the elevation dimension in order to focus the signals. In some embodiments, the 1.25D and 1.5D arrays may assume symmetry, wherein the gain and delay are symmetric about the center of the elevation dimension. The 1.75D array may apply different delays to each outer transducer element in elevation and may be configured to steer an acoustic beam. The 1.75D array may be symmetric about a center row of elements, or may be asymmetric.

[0057] The AFE circuit 310 is configured to perform signal processing on the electrical echo signals output by the transducer elements of the transducer array 312. For example, the AFE circuit 310 may include N gain controllers in channels corresponding to the N transducer elements, respectively, for adjusting the gain of the electrical echo signals. For example, the gain controller may be a time gain compensation (TGC) controller or an automatic gain control (AGC) controller. The AFE circuit 310 may include additional analog signal conditioning circuits, such as filters, operational amplifiers, etc., as will be apparent to those skilled in the art.

[0058] The digitization circuit 320 is configured to digitize the conditioned electrical echo signal output by the AFE circuit 310. The digitization circuit 320 may include N ADCs in channels corresponding to the N transducer elements, respectively, for digitizing the electrical echo signals output by the N gain controllers. The ADCs output N digital echo signals, respectively. For example, the output of each of the ADCs may be a 12-bit digital signal, although the ADCs may have any suitable bit rate (e.g., 4-bit, 8-bit, 16-bit, 24-bit, 32-bit, 64-bit).

[0059] In an embodiment, the ADC of the digitizing circuit 320 has an adjustable sampling rate, wherein the sampling rate (first sampling rate) for digitizing the electrical echo signal from the near field is higher than the sampling rate (second sampling rate) for digitizing the electrical echo signal from the far field. That is, a higher sampling rate is used for ultrasound imaging at a smaller depth within a medium (e.g., the anatomical structure of a patient), while a lower sampling rate is used for ultrasound imaging at a larger depth within the medium. This is because the ultrasound echo signal reflected from the near field has a higher frequency that has passed through less high-frequency attenuation tissue compared to the ultrasound signal reflected from the far field. In some cases, the system uses a higher frequency transmission excitation in the near field, further emphasizing the high-frequency nature of the near-field data. For example, the near-field sampling rate of the ADC can be twice the far-field sampling rate. Typically, the near-field sampling rate is at least 25% greater than the far-field sampling rate. A representative sampling rate switch 325 can be used to select different sampling rates, and the switch 325 can be controlled, for example, by the processor 260 to switch between the near-field signal generator 326 and the far-field signal generator 327. The near-field signal generator 326 provides a first signal that controls the ADC to sample the electrical echo signal at a first sampling rate for near-field imaging; and the far-field signal generator 327 provides a second signal that controls the ADC to sample the electrical echo signal at a second sampling rate for far-field imaging.

[0060] The probe 110 includes a combiner 330 and a near-field / far-field switch 340, which can be operated, for example, by the processor 260 for selecting near-field or far-field operation. The combiner 330 is configured to reduce the total number of channels from the digitization circuit 320, thereby reducing the data rate and thus reducing the digital bandwidth used to transmit data to the host system 130. In the depicted embodiment, the combiner 330 includes a multiplexer 334 for selecting digitized echo signals for near-field ultrasound imaging and a beamformer 336 for beamforming a subarray of digitized echo signals for far-field ultrasound imaging. The near-field / far-field switch 340 is operable to select the multiplexer 334 or the beamformer 336 according to near-field or far-field ultrasound imaging, respectively.

[0061] As reference below Figure 4Further discussed, the multiplexer 334 is configured to multiplex the digitized echo signals corresponding to the echo signals reflected from the near field so as to reduce the number of digitized echo signals. For example, in the depicted embodiment, the multiplexer 334 is an N:N / 2 multiplexer that selects half of the digital echo signals from half of the transducer elements in the azimuth direction indicated by the axis 399, respectively. Therefore, the combiner 330 reduces the number of channels from N channels to N / 2 channels. The transducer elements that provide the selected digital echo signals can be referred to as a first group of transducer elements, which contain less than all N transducer elements in the transducer array 312. The first group of transducer elements thereby defines a small aperture for receiving echo signals. The first group of transducer elements can have various arrangements relative to each other to provide different apertures within the transducer array 212. For example, the transducer elements can be adjacent to each other and grouped centered about the image line being acquired to provide an aperture for receiving echo signals reflected from the near field. Other arrangements of the first set of transducer elements may be implemented to provide unique benefits for any particular situation or to meet application-specific design requirements of the various embodiments, as will be apparent to those skilled in the art.

[0062] As reference below Figure 5 As further discussed, the beamformer 336 includes an adder configured to add the signals in the azimuth direction indicated by the axis 399 from the digitizing circuit 320 together into the subarray so that the digitized echo signal is less than the digitized echo signal provided by all the transducer elements in the transducer array 316. The transducer elements that provide the digital echo signals to be combined can be referred to as the second group of transducer elements. For example, the beamformer 336 can be an N:N / 2 beamformer that combines pairs of digital echo signals. In this case, each subarray contains two transducer elements of the transducer array 316. The beamformer 336 can also include a delay element arranged before the adder to delay the signal by a corresponding delay amount so as to focus the signal at the corresponding pixel being imaged. The beamformer 336 can be considered as a digital beamformer that performs a second stage of beamforming (delay and summation of signals) after the first stage of beamforming is completed by an optional analog beamformer (not shown). In the depicted embodiment, combiner 330 reduces the number of channels from N channels to N / 2 channels. Subarrays combining different numbers of digital echo signals may be implemented to provide unique benefits for any particular situation or to meet application-specific design requirements of various embodiments, as will be apparent to those skilled in the art.

[0063] The probe 110 also includes a digital processing unit 350, which may include a serializer and a high-speed current mode logic (CML) cable driver, which communicates with the combiner 330 via a near field / far field switch 340. For example, the digital processing unit 350 may be implemented using one or more processor circuits 210. The digital processing unit 350 may serialize the digitized echo signals output by the combiner 330 into a high-speed serial link and send the serialized data (e.g., B-mode data) to the host system 130 via a communication interface (not shown) and a signal conductor 360. The digital processing unit 350 may also rearrange the lines received from the combiner 330 and / or the digitization circuit 320 into a high data rate, serial, digital echo data stream. In some embodiments, the digital processing unit 350 may operate at a higher data rate than other circuits within the probe 110. For example, the echo data stream may operate at 2.4 GHz, while other circuits within the ultrasound channel may operate at 20 MHz.

[0064] The probe 110 is connected to the host system 130 via connecting conductors, including signal conductors 360 and power and control conductors 365. The signal conductors 360 and power and control conductors 365 may be formed together as a single cable or as multiple separate cables, or may be arranged in any other suitable configuration. The signal conductors 360 and power and control conductors 365 may be the same as those described above with reference to FIG. Figure 1 Portion of the communication link 150 discussed.

[0065] Signal conductor 360 can correspond to the reduced number of signal lines output from digital processing unit 350. In various embodiments, signal conductor 360 can include only a single signal line or can include multiple signal lines. Signal conductor 360 can be a twisted pair, a single conductor, a coaxial conductor or any other suitable communication path for transmitting data signals. In addition, in some embodiments, signal conductor 360 can only carry digital signals. In other embodiments, signal conductor 360 can also carry analog signals. In some embodiments, the signal can be carried by an optical link. In some embodiments, the signal can be carried wirelessly.

[0066] The power and control conductors 365 may include one or more signal and / or power lines, including conductors, twisted pairs, or any other suitable means for transmitting data, signals, or power. For example, the power and control conductors 365 may include conductors dedicated to providing control signals or other data from the host system 130 to the probe 110. The power and control conductors 365 may also include conductors that provide necessary AC and / or DC power from the host system 130 (or other power source) to components within the probe 110. The conductors may communicate with a controller or any other suitable component within the host system 130 (e.g., implemented by one or more processor circuits 210) and may provide signals for controlling clocks, switches, pulse generators, transducer arrays 312, AFE circuits 310, ADC circuits 320, combiners 330, digital processing units 350, and / or any other components within the probe 110. In various embodiments, the power and control conductors 365 may include only a single signal line or may include multiple signal lines. The power and control conductors 365 may be twisted pairs, single conductors, coaxial conductors, or any other suitable communication path for transmitting data signals.

[0067] The signal conductor 360 and the power and control conductor 365 may together form a circuit similar to the reference Figure 1 A connecting cable for the communication link 150 described herein. Specifically, the signal conductor 360 and the power and control conductor 365 can be wrapped together with the cable shield. The signal conductor 360, the power and control conductor 365, and any corresponding conductors packaged together can have any suitable length and / or can be flexible elongated members. For example, the length of the signal conductor 360, the power and control conductor 365, and all associated conductors can be one meter, two meters, three meters, or other suitable values, all larger, smaller, or therebetween. In other embodiments, the control conductor 365 and the power and control conductor 365 can form separate connecting cables of the same or different lengths.

[0068] During an ultrasound examination, the ultrasound imaging system 100 may specify a transmitting group of transducer elements of the transducer array 316 to transmit an ultrasound signal so that the ultrasound energy propagates into the patient's anatomical structure. The ultrasound imaging system 100 may also specify a group of receiving transducer elements (e.g., a first group of transducer elements or a second group of transducer elements) to receive reflected ultrasound echo signals. In some embodiments, the transducer elements selected to transmit the ultrasound signal may be the same transducer used to receive the reflected echo signal. In other embodiments, the transducer elements used to transmit the ultrasound signal may be different from the transducer elements used to receive the reflected echo signal. For example, the ultrasound imaging system 100 may select half of the transducer elements of the transducer array 316 to receive reflected echo signals from the patient's anatomical structure in the near field, as described above.

[0069] Figure 4 is a simplified block diagram of a transducer probe in an ultrasound imaging system for reducing digital bandwidth using a multiplexer according to a representative embodiment. The transducer probe is shown configured to receive echo signals reflected in a near field of a medium (eg, object 105).

[0070] refer to Figure 4 , the probe 110 includes a transducer array 312 having a plurality of transducer elements 405. For ease of explanation, the transducer array 112 is shown as a 1.0D array having a single row of N transducer elements 405. In the depicted configuration, representative transducer elements include a first transducer element 4051, a second transducer element 4052, a third transducer element 4053, a fourth transducer element 4054, ..., an N-3rd transducer element 4054, ..., an N-4th transducer element 4055, ..., an N-5th transducer element 4056, ..., an N-6th transducer element 4057, ..., an N-7th transducer element 4058, ..., an N-8th transducer element 4059, ..., an N-9th transducer element 4060, ..., an N-1 N-3 , N-2th transducer element 405 N-2 , N-1th transducer element 405 N-1 and the Nth transducer element 405 N . The transmitting portion of the transducer element 405 is configured to transmit an ultrasonic signal into a medium (e.g., the object 105). The receiving portion of the transducer element 405 is configured to receive an echo from the transmitted ultrasonic signal reflected within the medium and output a corresponding electrical echo signal. Each of the transmitting portion and the receiving portion may include one or more of the transducer elements 405 of the transducer array 412 (up to and including all of the transducer elements 405), and may include the same or different transducer elements 405 to provide unique benefits for any particular situation or to meet application-specific design requirements of various embodiments, as will be apparent to those skilled in the art.

[0071] The probe 110 also includes an AFE circuit 310, which includes at least a gain controller 415, which may be, for example, a TGC controller or an AGC controller. In the depicted configuration, the representative gain controller 415 includes a first gain controller 4151, a second gain controller 4152, a third gain controller 4153, a fourth gain controller 4154, ..., an N-3rd gain controller 415 N-3 , N-2th gain controller 415 N-2 , N-1th gain controller 415 N-1 and the Nth gain controller 415 N The gain controller 415 is configured to adjust the gain of the electrical echo signal output by the transducer element 405 in the corresponding channel.

[0072] The probe 110 also includes a digitizing circuit 320, which includes an ADC 425 having an adjustable sampling rate for sampling the analog echo signal, wherein the lower the sampling rate, the smaller the digital bandwidth of the digitized echo signal. In the depicted configuration, the representative ADC 425 includes a first ADC 4251, a second ADC 4252, a third ADC 4253, a fourth ADC 4254, ..., an N-3rd ADC 425 N-3 、N-2ADC425 N-2 、N-1ADC425 N-1 and NADC425 N The ADC 425 is configured to digitize the electrical echo signal received from the gain controller 415 in the corresponding channel. Each ADC 425 may have an adjustable sampling rate, wherein the sampling rate for the near-field configuration is greater than the sampling rate for the far-field configuration, as described below.

[0073] The probe 110 also includes a multiplexer 334 of the combiner 330. The multiplexer 334 is configured to receive the digitized echo signals respectively output by the ADC 425 via corresponding channels, and select some of the digitized echo signals for further processing by the digital processing unit 350. The fewer digitized echo signals selected by the multiplexer 334, the smaller the digital bandwidth of the digitized echo signals output by the multiplexer 334. For example, in the depicted embodiment, the multiplexer 334 is configured as an N:N / 2 multiplexer, which reduces the number of digitized echo signals by half. The selection of the digitized echo signals is performed between channels in the azimuth directions respectively corresponding to the selected transducer elements 405, for example, the transducer elements 405 form a small aperture for near-field imaging. The selected transducer elements 405 can be referred to as a first group of transducer elements. The operation of the multiplexer 334 for selecting channels can be performed automatically, for example using the processor circuit 210, or manually, for example using a user interface or GUI.

[0074] The digital processing unit 350 is configured to receive the multiplexed digitized echo signals from the multiplexer 334, for example, via the near-field / far-field switch 340 (not shown), and output a corresponding digital echo data stream having a smaller digital bandwidth than would have existed if the digitized echo signals from all ADCs 425 had been processed. When the multiplexer 334 is configured as an N:N / 2 multiplexer, the data rate of the echo data stream is N / 2×f s samples / second, where f s is the frequency of the electrical echo signal output by the transducer element 405 .

[0075] The probe 110 also includes a communication interface 355 configured to communicate the echo data stream from the digital processing unit 350 to the host system 130 via signal conductors 360. The operation of the multiplexer 334 reduces the number of digital echo signals so that the digital processing unit 350 provides an echo data stream having a total digital bandwidth that is less than the fixed maximum bandwidth of the communication interface.

[0076] Figure 5 1 is a simplified block diagram of a transducer probe in an ultrasound imaging system for reducing digital bandwidth using a beamformer according to another representative embodiment. The transducer probe is shown configured to receive echo signals reflected in the far field of a medium (eg, object 105).

[0077] refer to Figure 5 , the probe 110 includes a transducer array 312, which includes a plurality of transducer elements 405, as described above. The transducer elements 405 are configured to receive echo signals reflected in the far field, thereby defining a large aperture (e.g., which is larger than the small aperture formed by the transducer elements 405 for near-field imaging). The transducer elements 405 for receiving echo signals reflected in the far field can be referred to as a second group of transducer elements. For illustrative purposes, the probe 110 shows a second group of transducer elements consisting of all transducer elements 405 to form a large aperture for far-field imaging. Of course, without departing from the scope of the present teachings, the second group of transducer elements may include less than all transducer elements 405. Typically, far-field imaging requires determining the size of the large aperture for image reconstruction.

[0078] The probe 110 also includes an AFE circuit 310 and a digitizing circuit 320, the AFE circuit 310 including at least a gain controller 415, and the digitizing circuit 320 including an ADC 425, as described above. The gain controller 415 and the ADC 425 are respectively in channels associated with the transducer elements 405. In an embodiment, each of the ADCs 425 can have an adjustable sampling rate, wherein the sampling rate for the far-field configuration is greater than the sampling rate for the near-field configuration. Typically, fewer transducer elements 405 can be used for near-field imaging without affecting the quality because the signal attenuation of the echo from the medium at a shorter distance is smaller in near-field imaging. Therefore, instead of using each transducer element 405 to receive an echo signal, a smaller subset or "tile" of adjacent transducer elements 405 can be recorded while minimally affecting the resolution of the near-field image.

[0079] The probe 110 also includes a beamformer 336, which includes an adder 435 and (optionally) a delay circuit 438. In the depicted configuration, the representative adder 435 includes a first adder 4351, a second adder 4352, ..., an N / 2-1 adder 435, and an N / 2 adder 435. The adder 435 is configured to add together the digitized echo signals in the azimuth direction received from the ADC 425 to group the digitized echo signals into corresponding sub-arrays, which can be referred to as beamforming. For example, the first adder 4351 adds the digitized echo signals in the channels corresponding to the first transducer element 4051 and the first transducer element 4051, respectively, and the second adder 4352 adds the digitized echo signals in the channels corresponding to the third transducer element 4053 and the fourth transducer element 4054, respectively, and so on. The grouping results in fewer digitized echo signals than are provided by all transducer elements 405 in the transducer array 312. The transducer elements 405 that provide the digital echo signals to be combined into the sub-arrays may be referred to as a second group of transducer elements. In the depicted embodiment, the beamformer 336 is an N:N / 2 beamformer that combines pairs of digital echo signals so that the corresponding transducer elements 405 are organized into two sub-arrays. This reduces the number of digitized echo signals output by the beamformer 336 by half. The operation of the beamformer 336 for combining channels may be performed automatically, for example, using the processor circuit 210, or manually, for example, using a user interface or GUI.

[0080] The digital processing unit 350 is configured to receive a subarray of digitized echo signals from the beamformer 336, for example, via the near-field / far-field switch 340 (not shown), and output a corresponding digital echo data stream having a smaller digital bandwidth than would have existed if the digitized echo signals from all ADCs 425 had been processed. When the beamformer 336 is configured as an N:N / 2 beamformer, the data rate of the echo data stream is N / 2×f s samples / second, where f s is the frequency of the electrical echo signal output by the transducer element 405. The echo data stream output by the digital processing unit 350 is delivered to the host system 130 via a communication interface (not shown) and a signal conductor 360, wherein the communication interface has a fixed maximum bandwidth. The operation of the beamformer 336 reduces the number of digital echo signals so that the digital processing unit 350 provides an echo data stream having a total digital bandwidth that is less than the fixed maximum bandwidth of the communication interface.

[0081] As described above, the beamformer 336 may also include a delay circuit 438, which may be implemented as, for example, a digital RAM or a first-in-first-out (FIFO) buffer. In the depicted configuration, the representative delay circuit 438 includes a first delay circuit 4381, a second delay circuit 4382, a third delay circuit 4383, a fourth delay circuit 4384, ..., an N-3rd delay circuit 4385, ..., and a N-4th delay circuit 4386. N-3 , N-2th delay circuit 438 N-2 , N-1th delay circuit 438 N-1 and the Nth delay circuit 438 N The delay circuit 438 is configured to delay the digitized echo signal by a corresponding delay amount so as to focus the digitized signal at the corresponding pixel being imaged. The delay amount may be determined by a digital "focus engine" state machine (not shown), as will be apparent to one skilled in the art. The delay amount may be the same or a different amount than the delay circuit 438.

[0082] Summing the digitized echo signals into subarrays reduces the digital bandwidth of the digitized echo signals by a factor of the number of digitized echo signals being added together. In the depicted configuration, for example, each subarray combines digitized second echo signals from pairs of transducer elements 405, where the two transducer elements 405 in each pair are adjacent to each other. Of course, other sizes of subarrays and arrangements of transducer elements 405 combined in a subarray may vary without departing from the scope of the present teachings.

[0083] Probe 110 also includes a communication interface 355 configured to communicate the echo data stream from digital processing unit 350 to host system 130 via signal conductors 360. Summer 335 reduces the digitized second echo signals to a number that provides an echo data stream having a total digital bandwidth less than a fixed maximum bandwidth of communication interface 355.

[0084] In various embodiments, Figure 4 and Figure 5 The configurations of the probe 110 shown can be combined to complement each other. For example, the probe 110 can be configured to reduce the digital bandwidth of the echo data stream by utilizing different apertures for receiving echoes in the near field and the far field, respectively, wherein the respective apertures are defined by the number of transducer elements 405. For example, a small aperture including less than all transducer elements 405 (e.g., half (N / 2)) can be used for near-field imaging, and a large aperture including all transducer elements 405 (N) can be used for far-field imaging.

[0085] In this example, the transducer elements 405 include a first group of transducer elements consisting of half of the total number of transducer elements 405, the first group of transducer elements being configured to receive a first echo signal in response to an ultrasonic signal being reflected in a near field, and output a corresponding first electrical echo signal. The first group of transducer elements includes less than all transducer elements 405 transducer elements, thereby defining a small aperture. The transducer elements 405 also include a second group of transducer elements consisting of the entire total number of transducer elements 405, the second group of transducer elements being configured to receive a second echo signal in response to an ultrasonic signal being reflected in a far field, and output a corresponding second electrical echo signal. The second group of transducer elements does not necessarily include all transducer elements 405, but includes more transducer elements 405 than the first group of transducer elements.

[0086] In addition, in an embodiment, the ADC 425 receiving the first electrical echo signal from the selected transducer element 405 of the small aperture digitizes the first electrical echo signal at a first sampling rate, and the ADC 425 receiving the second electrical echo signal from the transducer element 405 of the large aperture digitizes the second echo signal at a second sampling rate, wherein the first sampling rate is different from the second sampling rate. For example, the first sampling rate can be at least 25% greater than the second sampling rate, such as the first sampling rate can be twice the second sampling rate. In this case, the lower sampling rate of the larger number of echo signals from the second group of transducer elements further reduces the digital bandwidth of the echo data stream.

[0087] In an embodiment, switching circuits may be used to combine the functionality of the multiplexer 334 and the beamformer 336 of the combiner 330 . Figure 6 is a simplified block diagram of a switching circuit for a transducer probe in an ultrasound imaging system for reducing digital bandwidth according to another representative embodiment.

[0088] refer to Figure 6 , the combiner 330' includes a switch circuit 630, which is repeated multiple times in parallel (for example, four times in the illustrative configuration) to provide sufficient switching capacity. The switch circuit 630 is configured to receive digitized echo signals via channels (signal paths) corresponding to the transducer elements 405, which provide echo signals reflected in the near field and / or the far field, respectively. Each pair of channels is provided to a multiplexing switch and a beamforming switch, which is activated to select one of the two channels for near-field imaging or to combine the two channels for far-field imaging. For example, the operation of the switch circuit 630 can be performed by the processor circuit 210.

[0089] In particular, the switch circuit 630 includes a first multiplexing switch 631, a first adder 635, and a first beamforming switch 641, and a second multiplexing switch 632, a second adder 645, and a second beamforming switch 642. The first multiplexing switch 631 is configured to select a first channel Ch1 corresponding to the first transducer element 4051 or a second channel Ch2 corresponding to the first transducer element 4052. The transducer element (not shown) Channel One of the options is to digitize the echo signal. The transducer element is the first transducer element in the second half of the N transducer elements. ) The first adder 635 is configured to add the digitized echo signals from the first channel Ch1 and the second channel Ch2. The first beamforming switch 641 is configured to select the multiplexed output of the first multiplexing switch 631 or the summed output of the first adder 635. When the first beamforming switch 641 selects the multiplexed output of the first multiplexing switch 631, the digitized echo signal corresponding to the channel selected by the first multiplexing switch 631 is output from the combiner 330'. When the first beamforming switch 641 selects the output of the first adder 635, the combined (beamformed) digitized echo signal from the first adder 635 is output from the combiner 330'.

[0090] Similarly, the second multiplexing switch 632 is configured to select either the second channel Ch2 corresponding to the second transducer element 4052 or the second channel Ch3 corresponding to the first transducer element 4053. The transducer element (not shown) Channel The second adder 645 is configured to add the digitized echo signal from the first Channel and Channel The second beamforming switch 642 is configured to select the multiplexed output of the second multiplexing switch 632 or the summed output of the second adder 645. When the second beamforming switch 642 selects the multiplexed output of the second multiplexing switch 632, the digitized echo signal corresponding to the channel selected by the second multiplexing switch 632 is output from the combiner 330'. When the second beamforming switch 642 selects the output of the second adder 645, the combined (beamformed) digitized echo signal from the second adder 645 is output from the combiner 330'.

[0091] Figure 7 is a flow chart of a method for controlling an ultrasound transducer probe including a transducer array having a plurality of transducer elements according to a representative embodiment. The method may be implemented, for example, using the probe 110 described above.

[0092] refer to Figure 7 In block S711, echo signals are received at a plurality of transducer elements of a transducer array (e.g., transducer array 312), and corresponding electrical echo signals are output by the transducer elements. The echo signals are responsive to ultrasound signals emitted by at least some of the transducer elements, wherein the echo signals are reflected in a near field and / or a far field of a medium (e.g., object 105), such as an anatomical structure of a patient. The transducer elements may be arranged in a 1.X-dimensional transducer array.

[0093] In block S712, the electrical echo signal is digitized to provide a corresponding digitized echo signal. The electrical echo signal may be digitized by an ADC (e.g., ADC425) located in a channel corresponding to a transducer element of the transducer array. In an embodiment, the ADC may digitize the electrical echo signal at different sampling rates, depending on whether the electrical echo signal corresponds to an echo signal reflected in a near field or a far field. Typically, an electrical echo signal corresponding to an echo signal reflected in a near field is digitized at a first sampling rate, and an electrical echo signal corresponding to an echo signal reflected in a far field is digitized at a second sampling rate, wherein the first sampling rate is higher than the second sampling rate. For example, the first sampling rate may be at least 25% greater than the second sampling rate, or the first sampling rate may be at least twice the second sampling rate.

[0094] In block S713, a first set of digitized echo signals is selected for receiving echo signals reflected in the near field, the first set of digitized echo signals corresponding to a first set of transducer elements in the plurality of transducer elements. The first set of transducer elements includes fewer transducer elements than the sum of all transducer elements. The first set of transducer elements thereby defines a small aperture.

[0095] In box S714, a second group of digitized echo signals is selected for receiving echo signals reflected in the far field, and the second group of digitized echo signals corresponds to a second group of transducer elements in a plurality of transducer elements. The second group of transducer elements includes more transducer elements than the first group of transducer elements. For example, the second group of transducer elements may include all of the plurality of transducer elements. Therefore, the second group of transducer elements defines a large aperture. The first and second groups of digitized echo signals may be selected by manual or automatic operation of a switch (e.g., near field / far field switch 340).

[0096] Small aperture and large aperture are relative terms, where a small aperture means fewer transducer elements than all transducer elements in a transducer array, and a large aperture means more transducer elements than make up the small aperture. A larger number of transducer elements in a large aperture for far-field imaging compensates for increased attenuation of echo signals from the medium at greater distances in far-field imaging compared to a small aperture for near-field imaging. A small aperture typically includes no more than half of all transducer elements in a transducer array, and a large aperture typically includes all transducer elements in a transducer array, but other arrangements of small and large apertures may be provided without departing from the scope of the present teachings.

[0097] In block S715, the echo data stream is output to the host via a communication interface having a fixed maximum bandwidth. The echo data stream includes a first group and / or a second group of digitized echo signals. The small aperture defined by the first group of transducer elements for near-field imaging provides a digital bandwidth of the echo data stream that is less than the maximum bandwidth of the communication interface. Similarly, the beamforming of the digitized echo signals from the second group of transducer elements for far-field imaging provides a digital bandwidth of the echo data stream that is less than the maximum bandwidth of the communication interface.

[0098] Thus, according to various embodiments, when imaging in the near field, the aperture is small compared to the total transmit aperture. Rather than using every channel for reception, a smaller subset (or "tile") of adjacent channels (signal paths) can be recorded while minimally affecting the resolution of the image. In this mode, each of the channels in the tile is configured for reception. The signal is digitized and sent off-chip. Near-field reconstruction may require as few as half the total number of channels compared to the full aperture required for the far field, thereby reducing the overall necessary data rate. When imaging in the far field, the imaging requirement determines the size of the larger aperture used for image reconstruction. To reduce data, a subarray (e.g., pair) of azimuth channels can be beamformed during reception. The beamformed pairs are then digitized and sent off-chip. Beamforming reduces the number of channels digitized by a factor of two, thereby reducing the overall necessary data rate. By combining the near-field receive profile and the far-field receive profile, an improved profile can be made that simulates the quality of a larger aperture beam profile where all transducer elements are recorded. This combination effectively reduces the required data rate on an ultrasound imaging system having any number of channels.

[0099] Although the methods, systems, and components for implementing imaging protocols have been described with reference to several exemplary embodiments, it should be understood that the words that have been used are words of description and illustration, rather than words of limitation. The foregoing description of the disclosed embodiments is provided to enable those skilled in the art to practice the concepts described in the present disclosure. Therefore, to the maximum extent allowed by law, the scope of the present disclosure will be determined by the broadest permissible interpretation of the appended claims, and shall not be limited or restricted by the foregoing detailed description.

[0100] The Abstract of the present disclosure is provided to comply with 37 CFR § 1.72 (b) and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, various features may be grouped together or described in a single embodiment for the purpose of simplifying the present disclosure. This disclosure should not be interpreted as reflecting an intention that the claimed embodiments require more features than those expressly recited in each claim. On the contrary, as reflected in the following claims, the inventive subject matter may involve less than all the features of any disclosed embodiment. Therefore, the following claims are incorporated into the Detailed Description, wherein each claim independently defines the subject matter that is individually claimed.

Claims

1. A transducer probe (110) of an ultrasonic imaging system, comprising: a transducer array (312) comprising a plurality of transducer elements configured to: transmit an ultrasonic signal into a medium, receive echo signals in response to the ultrasonic signal being reflected in a near field and a far field of the medium, and output corresponding electrical echo signals; a plurality of analog-to-digital converters (ADCs) (320) configured to digitize the electrical echo signals to provide digitized echo signals; A combiner (330) comprising: a multiplexer (334) configured to multiplex the digitized echo signals to output a first group of digitized echo signals, the first group of digitized echo signals corresponding to a first group of transducer elements of the plurality of transducer elements, the first group of transducer elements defining a small aperture for receiving the echo signals reflected in the near field; and a beamformer (336) comprising a plurality of adders configured to: group transducer elements of a second group of transducer elements into subarrays providing a second group of digitized echo signals, and add together the digitized echo signals from the second group of transducer elements within each subarray, each subarray being configured to receive the echo signals reflected in the far field, wherein the second group of transducer elements comprises more transducer elements than the first group of transducer elements; a switch (340) operable to select the multiplexer for near-field ultrasound imaging and the beamformer for far-field ultrasound imaging; a digital processing unit (350) configured to: receive the first group of digitized echo signals and the second group of digitized echo signals, and output corresponding digital echo streams; and a communication interface configured to transmit the echo data stream to an ultrasound imaging system host, wherein the communication interface has a fixed maximum bandwidth, Wherein the small aperture defined by the first set of transducer elements provides a digital bandwidth of the echo data stream that is less than the fixed maximum bandwidth of the communication interface.

2. The transducer probe according to claim 1, wherein: The electrical echo signals are digitized at a first sampling rate to provide the first set of digitized echo signals, and the electrical echo signals are digitized at a second sampling rate to provide the second set of digitized echo signals, wherein the first sampling rate is different from the second sampling rate, wherein, preferably, the first sampling rate is at least 25% greater than the second sampling rate.

3. The transducer probe according to claim 1 or 2, wherein: Each sub-array includes two of the transducer elements of the second group of transducer elements.

4. A transducer probe according to any preceding claim, wherein: The beamformer further comprises: A plurality of delay elements are arranged before the plurality of adders and are configured to delay the digitized echo signals by corresponding delay amounts so as to focus the digitized echo signals at corresponding pixels being imaged.

5. A transducer probe according to any preceding claim, wherein: The combiner also includes: a sampling rate switch configured to selectively connect the plurality of ADCs to the first signal generator or the second signal generator, The first signal generator is configured to: provide a first signal, the first signal controls the plurality of ADCs to sample the electrical echo signals at a first sampling rate for near-field imaging; and provide a second signal, the second signal controls the plurality of ADCs to sample the electrical echo signals at a second sampling rate for far-field imaging, and The first sampling rate is greater than the second sampling rate.

6. A transducer probe according to any preceding claim, wherein: The transducer array comprises a 1.X dimensional array.

7. A transducer probe according to any preceding claim, wherein: The multiplexer comprises an N:N / 2 multiplexer.

8. A hand-held ultrasound scanner comprising a transducer probe according to any preceding claim.

9. A method of controlling an ultrasound transducer probe, the ultrasound transducer probe comprising a transducer array having a plurality of transducer elements, the method comprising: receiving echo signals at the plurality of transducer elements in response to ultrasonic signals emitted by at least some of the plurality of transducer elements (S711), wherein the echo signals are reflected in a near field and a far field of a medium; and outputting corresponding electrical echo signals; digitizing the electrical echo signal (S712) to provide a digitized echo signal; multiplexing the digitized echo signals to output a first group of digitized echo signals, the first group of digitized echo signals corresponding to a first group of transducer elements of the plurality of transducer elements, the first group of transducer elements defining a small aperture for receiving the echo signals reflected in the near field; grouping transducer elements in the second set of transducer elements into subarrays that provide a second set of digitized echo signals; adding together the digitized echo signals from the second group of transducer elements within each subarray, each subarray being configured to receive echo signals reflected in the far field, wherein the second group of transducer elements comprises more transducer elements than the first group of transducer elements; and outputting an echo data stream to a host system via a communication interface having a fixed maximum bandwidth (S715), wherein the echo data stream includes the first group of digitized echo signals and the second group of digitized echo signals, Wherein the small aperture defined by the first set of transducer elements provides a digital bandwidth of the echo data stream that is less than the fixed maximum bandwidth of the communication interface.

10. The method according to claim 9, wherein: The electrical echo signals are digitized at a first sampling rate to provide the first set of digitized echo signals, and the electrical echo signals are digitized at a second sampling rate to provide the second set of digitized echo signals, wherein the first sampling rate is different from the second sampling rate, wherein, preferably, the first sampling rate is at least 25% greater than the second sampling rate.

11. The method according to claim 9 or 10, wherein: Each sub-array includes two of the transducer elements of the second group of transducer elements.

12. The method according to any one of claims 9 to 11, wherein: Prior to adding together the digitized echo signals from the second group of transducer elements, the method further comprises: The digitized echo signal is delayed by a corresponding delay amount so as to focus the digitized echo signal at a corresponding pixel being imaged.

13. The method according to any one of claims 9 to 12, wherein: The transducer array comprises a 1.X dimensional array.

14. The method according to any one of claims 9 to 13, wherein: The digitized echo signals are multiplexed using an N:N / 2 multiplexer.

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