Patent Description:
<CIT>, <CIT>, and <CIT> show background art.

Ultrasound imaging systems are often used for medical imaging. An ultrasound imaging system typically includes a transducer probe as well as a main processing system. The transducer probe may include an array of ultrasound transducer elements. The ultrasound transducer elements send acoustic waves through a patient's body and subsequently record echo signals as the acoustic waves are reflected back by the tissues and/or organs within the patient's body. The timing and/or strength of the echo signals may correspond to the size, shape, and mass of the tissues, organs, or other features of the patient. The tissues, organs, or other features of the patient may be displayed to a user of the ultrasound system.

Ultrasound imaging systems use various types of transducer arrays. For example, ultrasound systems may have one-dimensional arrays or two-dimensional matrix arrays. While a two-dimensional matrix arrays provides maximum ability to focus or steer an imaging beam, two-dimensional matrix arrays require many transducer elements and can be costly. X-dimensional transducer arrays may require fewer transducer elements but still preserve some aspects of control in the elevational direction, including the ability to focus the ultrasound imaging beam at varying depths. However, to focus an ultrasound imaging beam with a <NUM>. X-dimensional array often requires complex circuitry with many electrical components leading to increased cost of an ultrasound imaging system.

Embodiments of the present disclosure are systems, devices, and methods for ultrasound imaging using a <NUM>. X-dimensional transducer array. An ultrasound system may include a host, a probe, and a connecting cable. The ultrasound imaging probe may include a <NUM>. X-dimensional transducer array. The transducer array may transmit ultrasound signals toward a region of a patient's anatomy and receive reflected waves to form an image. Elevational rows of ultrasound transducers positioned on either side of a center row of transducers may be used to focus the ultrasound imaging beam. As the imaging depth increases, or as the distance between the region to be imaged and the ultrasound probe increases, the gain of outer elevational transducers may be gradually increased. This increase in gain of outer elevational elements effectively increases the elevation size of the aperture of the transducer array and results in increased data quality for regions deeper in the anatomy.

According to the invention separate gain profiles are applied to outer elevational elements and center elements to gradually increase the gain of the outer transducer elements. Other embodiments apply a common gain profile to all transducer elements and apply a weighting profile to the outer transducer elements to gradually increase the gain of the outer elements. Still other embodiments facilitate focusing of the imaging beam by converting received analog signals to digital signals and applying a delay to the outer and/or inner transducer elements. The disclosed embodiments provide increased signal and image quality at varying depths within a patient's anatomy while reducing required circuitry resulting in a simpler, more cost-effective ultrasound imaging probe.

Illustrative embodiments of the present invention will be described with reference to the accompanying drawings, of which:.

For the purposes of promoting an understanding of the principles of the present invention reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It is nevertheless understood that no limitation to the scope of the claimed invention is intended. Any alterations and further modifications to the described devices, systems, and methods, and any further application of the principles of the present claimed invention are fully contemplated.

<FIG> is a schematic diagram of an ultrasound imaging system, according to aspects of the present disclosure. The system <NUM> is used for scanning a region, area, or volume of a patient's body. The system <NUM> includes an ultrasound imaging probe <NUM> in communication with a host <NUM> over a communication link <NUM>. At a high level, the probe <NUM> emits ultrasound waves towards an anatomical object <NUM> (e.g., a patient's body) and receives ultrasound echoes that are reflected from the object <NUM>. The probe <NUM> transmits electrical signals representative of the received echoes over the link <NUM> to the host <NUM> for processing and image display. The signals representative of the received echoes can be transmitted over the link <NUM> in analog format, digital format, and/or both analog and digital formats. The probe <NUM> may be in any suitable form for imaging various body parts of a patient while positioned inside or outside of the patient's body. For example, the probe <NUM> may be in the form of a handheld ultrasound scanner, such as a transthoracic echocardiography (TTE) probe, or a patch-based ultrasound device. In some embodiments, the ultrasound probe is not handheld and is rather held in place via a strap, mechanical holder, and/or adhesive. In some embodiments, the probe <NUM> can be a catheter, a transesophageal echocardiography (TEE) probe, or other an endo-cavity or intraluminal probe. The probe <NUM> may include any of the components shown in <FIG>. Any of the components of the probe <NUM> may be positioned or stored in a housing <NUM>. When the probe <NUM> is a handheld probe, the housing <NUM> is configured to be grasped by the hand of a user.

The probe <NUM> includes a transducer array <NUM>, circuitry <NUM>, and a communication interface <NUM>, all of which may be mechanically coupled to the housing of the probe <NUM>. The transducer array <NUM> emits ultrasound signals towards the object <NUM> and receives echo signals reflected from the object <NUM> back to the transducer array <NUM>. The transducer array <NUM> includes an array of acoustic elements. In an exemplary embodiment, the transducer array <NUM> is a <NUM>. X-dimensional array, such as a <NUM>. 25D array or a <NUM>. The acoustic elements may be referred to as transducer elements. Each transducer element can emit ultrasound waves towards the object <NUM> and can receive echoes as the ultrasound waves are reflected back from the object <NUM>. Each transducer element generates an analog electrical signal representative of the received ultrasound echoes. The transducer array <NUM> can include M transducer elements producing M analog ultrasound echo channel signals <NUM>. In some embodiments, M can be about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and/or other suitable values larger, smaller, or therebetween.

Circuitry <NUM> positioned within the probe <NUM> may be any of any suitable type and may serve several functions. For example, circuitry <NUM> may include resistors, capacitors, transistors, inductors, relays, clocks, timers, or any other suitable electrical component that may be integrated in an integrated circuit. In addition, circuitry <NUM> may be configured to support analog signals and/or digital signals transmitted to or from the transducer array <NUM> and/or the probe <NUM>. In some embodiments, circuitry <NUM> may include analog frontends (AFEs), analog-to-digital converters (ADCs), multiplexers (MUXs), and encoders, among various other components. In some embodiments, the circuitry <NUM> can include hardware components, software components, and/or a combination of hardware components and software components.

The communication interface <NUM> is coupled to the circuitry <NUM> via L signal lines. In some embodiments, circuitry <NUM> may reduce the number of required lines from M signal lines to L signal lines. This may be accomplished by any suitable method using any suitable component. For example, MUXs, beamformers, or other components may be used to reduce the M signal lines from the transducer array <NUM> to L signal lines <NUM>. In the embodiment of <FIG>, L is less than M. The communication interface <NUM> is configured to transmit the L signals <NUM> to the host <NUM> via the communication link <NUM>. The communication interface <NUM> may include a combination of hardware components and software components configured to generate signals <NUM> carrying the information from signals <NUM> for transmission over the communication link <NUM>. In an exemplary embodiment, the signals <NUM> are digital signals such that digital ultrasound data is transmitted from the probe <NUM> to the host <NUM>. The communication link <NUM> may include L data lanes for transferring the digital signals <NUM> to the host <NUM>.

The host <NUM> may be any suitable computing and display device, such as a workstation, a personal computer (PC), a laptop, a tablet, a mobile phone, or a patient monitor. In some embodiments, the host <NUM> may be located on a moveable cart. At the host <NUM>, the communication interface <NUM> may receive the digital signals <NUM> from the communication link <NUM>. The communication interface <NUM> may include hardware components, software components, or a combination of hardware components and software components. The communication interface may be substantially similar to the communication interface <NUM> in the probe <NUM>.

Circuitry <NUM> positioned within the host <NUM> may be of any suitable type and may serve any suitable function. For example, circuitry <NUM> may include resistors, capacitors, transistors, inductors, relays, clocks, timers, processing components, memory components, or any other suitable electrical component that may be integrated in an integrated circuit. In addition, circuitry <NUM> may be configured to support analog signals and/or digital signals transmitted to or from the probe <NUM>. Circuitry <NUM> may be configured to process digital signals <NUM> received from the probe <NUM>. For example, circuitry <NUM> may expand L signal lines received from the probe <NUM> to the original M signal lines corresponding to the specific transducer elements or groups or patches of transducer elements within the transducer array <NUM>. Circuitry <NUM> may be configured to generate image signals <NUM> 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.). Circuitry <NUM> may additionally include a central processing unit (CPU), a digital signal processor (DSP), a graphical processing unit (GPU), an application-specific integrated circuit (ASIC), a controller, a field-programmable gate array (FPGA), another hardware device, a firmware device, or any combination thereof. Circuitry <NUM> may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a GPU and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. Circuitry <NUM> can be configured to generate image signals <NUM> for display to a user and/or perform image processing and image analysis for various diagnostic modalities.

The display unit <NUM> is coupled to circuitry <NUM>. The display unit <NUM> may include a monitor, a touchscreen, or any suitable display. The display unit <NUM> is configured to display images and/or diagnostic results processed by circuitry <NUM>. The host <NUM> may further include a keyboard, a mouse, a touchscreen, or any suitable user-input components configured to receive user inputs for controlling the system <NUM>.

While <FIG> is described in the context of transferring detected ultrasound echo data from the probe <NUM> to the host <NUM> for display, the host <NUM> can generate and transmit control signals for controlling the probe <NUM>, for example, the excitations of the transducer elements at the transducer array <NUM>.

<FIG> is a schematic diagram of a processor circuit, according to aspects of the present disclosure. The processor circuit <NUM> may be implemented in the probe <NUM>, the host system <NUM> of <FIG>, or any other suitable location. One or more processor circuits can be configured to carry out the operations described herein. The processor circuit <NUM> can be part of the circuitry <NUM> and/or circuitry <NUM>, or may be a separate circuitry. In an example, the processor circuit <NUM> may be in communication with the transducer array <NUM>, circuitry <NUM>, communication interface <NUM>, communication interface <NUM>, circuitry <NUM>, and/or the display <NUM>, as well as any other suitable component or circuit within ultrasound system <NUM>. As shown, the processor circuit <NUM> may include a processor <NUM>, a memory <NUM>, and a communication module <NUM>. These elements may be in direct or indirect communication with each other, for example via one or more buses.

The processor <NUM> may include a CPU, a GPU, a DSP, an application-specific integrated circuit (ASIC), a controller, an FPGA, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

The memory <NUM> may include a cache memory (e.g., a cache memory of the processor <NUM>), 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 drives, other forms of volatile and non-volatile memory, or a combination of different types of memory. In an embodiment, the memory <NUM> includes a non-transitory computer-readable medium. The instructions <NUM> may include instructions that, when executed by the processor <NUM>, cause the processor <NUM> to perform the operations described herein with reference to the probe <NUM> and/or the host <NUM> (<FIG>). Instructions <NUM> may also be referred to as code. The terms "instructions" and "code" should be interpreted broadly to include any type of computer-readable statement(s). For example, the terms "instructions" and "code" may refer to one or more programs, routines, sub-routines, functions, procedures, etc. "Instructions" and "code" may include a single computer-readable statement or many computer-readable statements.

The communication module <NUM> can include any electronic circuitry and/or logic circuitry to facilitate direct or indirect communication of data between the processor circuit <NUM>, the probe <NUM>, and/or the host <NUM> and/or display <NUM>. In that regard, the communication module <NUM> can be an input/output (I/O) device. In some instances, the communication module <NUM> facilitates direct or indirect communication between various elements of the processor circuit <NUM> and/or the probe <NUM> (<FIG>) and/or the host <NUM> (<FIG>).

<FIG> is a schematic diagram illustrating example circuitry of an ultrasound imaging system <NUM> with a <NUM>. X-dimensional transducer array, according to aspects of the present disclosure. For example, <FIG> provides a more detailed view of circuitry within the probe <NUM>. As shown in <FIG>, the circuitry of the probe <NUM> includes the transducer array <NUM>. The transducer array <NUM> is in communication with a plurality of circuits or circuitry <NUM> via a number of conductors <NUM>, including conductor <NUM>, conductor <NUM>, conductor <NUM>, and conductor <NUM> among others. Any of the conductors <NUM> may additionally be referred to as conductive pathways or conductive traces. The probe <NUM> may additionally include a combiner <NUM>, and a serializer and/or high speed current mode logic cable driver (CML) <NUM>. As shown in <FIG>, the host <NUM> may also be in communication with the probe <NUM> via a number of connecting conductors. Specifically, the connecting conductors may include a power and control conductors <NUM>, and multiple transducer conductors <NUM>. The connecting conductors, including the power and control conductors <NUM> and the transducer conductors <NUM> may together form a cable, may form multiple separate cables, or may be arranged in any other suitable configuration. Any of the components of the probe <NUM> may be positioned or stored in a housing.

In some embodiments, the transducer array <NUM> is a <NUM>. X-dimensional array. For example, the transducer array <NUM> may be a <NUM>. 25D array, <NUM>. 5D array, <NUM>. 75D array, or any suitable type of <NUM>. X-dimensional array. In some aspects, a <NUM>. 25D array may include circuitry for controlling the aperture size in elevation. 5D array may include additional circuitry configured to apply various delays to received signals from elements in the elevation dimension so as to focus these signals. In some embodiments, <NUM>. 25D and <NUM>. 5D arrays may assume symmetry where gain and delay are symmetric about the center of the elevation dimension. 75D array may apply different delays to each of the outer elements in elevation and may be configured to steer the acoustic beam. 75D arrays may be symmetrical about a center row of elements or may be asymmetrical.

As an example, the transducer array <NUM> shown in <FIG> is a <NUM>-dimensional array. Axes <NUM> and <NUM> provide orientation directions of the transducer array <NUM> shown in <FIG>. Specifically, the axis <NUM> illustrates the elevational or elevation direction and the axis <NUM> illustrates the azimuthal or lateral direction. The transducer array <NUM> includes one row of inner transducer elements 305b, and two rows of outer transducer elements 305a, one on either side of the inner row 305b in the elevational direction. The outer elements 305a include twice as many transducer elements as the inner elements 305b and are positioned such that one outer element 305a is positioned above each inner element 305b in the elevational direction and one outer element 305a is positioned below each inner element 305b in the elevational direction as shown in <FIG>. The embodiment shown in <FIG> with one row of inner elements 305b and two rows of outer elements 305a may be referred to as three elements in elevation or three rows of elements in elevation. In some embodiments, the transducer array <NUM> can include only the three rows of elements shown in <FIG>. In other embodiments, the transducer array <NUM> includes additional rows of elements. In other embodiments, the transducer array <NUM> may include <NUM> rows of transducer elements in elevation, <NUM> rows of transducer elements in elevation, <NUM> rows, or more. Some embodiments of the present disclosure include symmetrical rows of transducer elements such that odd numbers of rows of transducer elements are used. Similar to the transducer array <NUM> shown in <FIG>, embodiments with additional outer rows of transducer elements may also couple outer rows such that outer rows are driven together. For example, two outer rows positioned directly next to and on either side of the center row may be coupled together, two more outer rows adjacent to and on either side of the first outer rows may also be coupled together, and so on. For example, the rows 305a are coupled together.

In other embodiments, the rows 305a may alternatively be only a single row of transducer elements positioned either above or below the transducer row 305b in the elevation direction <NUM>. In such an embodiment, the transducer array <NUM> may include only two rows of transducer elements. In still other embodiments, the transducer array <NUM> may include an even number of rows of transducer element greater than two.

As will be discussed in more detail hereafter, different gain profiles are applied to different rows of transducer elements for imaging at different depths within the patient anatomy. For example, in the embodiment shown in <FIG>, only signals received from the inner row 305b may be used for imaging at locations near to the transducer array <NUM>. Alternatively, when imaging at locations farther from the transducer array <NUM>, the signals from the outer rows 305a may be gradually added to widen the aperture of the array in elevation. For simplicity's sake, description of various components within the probe <NUM> is given with reference to an odd number of rows wired in a symmetric manner (e.g., the three-row configuration of transducer elements shown in <FIG>). However, it is fully contemplated that additional numbers of rows may be implemented according to the same principles presented.

In an embodiment with only two transducer rows, a row 305b and only one single row 305a positioned above or below the row 305b, signals received from the transducer elements of the row 305b may be used to for near field imaging and signals from both the row 305b and the row 305a may be used for far field imaging. In such an embodiment, the resulting near field and far field beams may be slightly mis-aligned but the misalignment may remain within a clinically acceptable amount. An embodiment in which only two rows of transducers are disposed within the transducer array <NUM> may reduce manufacturing cost by reducing the number of required transducer elements and does not require the electrical coupling between outer elements as shown in <FIG>. The present invention could also be applied to such embodiments with the description regarding inner elements related to the row used for near field imaging and the description regarding outer elements related to the row that is additionally used for far field imaging.

A transducer row within the transducer array <NUM> may include any suitable number of transducer elements. For example, the row of transducer elements 305b and the two rows of transducer elements 305a all may each include <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> transducer elements, or any suitable number larger, smaller, or therebetween. Each row of transducer elements <NUM> may include an odd or an even number of transducer elements. In some embodiments, as shown in <FIG>, the transducer array <NUM> may additionally be organized in columns <NUM>. For example, a column of transducers 301a is at an azimuthal or lateral end of the transducer array <NUM> on the left side of <FIG>. As shown in <FIG>, the column 301a includes three transducer elements: one center transducer element 305b and two outer elements 305a. The center transducer element may also be called a first transducer element and the outer transducer elements may be called a second transducer element and a third transducer element. In an embodiment in which the transducer array <NUM> includes <NUM> rows of transducer elements, column 301a would include <NUM> transducer elements and so on. Adjacent and to the right of column 301a in the azimuthal direction, column 301b is shown. Column 301b also includes three transducer elements: one center element 305b and two outer elements 305a. Although not labelled, the transducer column adjacent and to the right of column 301b may be an additional column 301c and so on as indicated by the ellipses. Transducer columns <NUM> may continue in like manner until a column <NUM>. Columns 301a through <NUM> may represent a first portion of the transducer columns. For example, columns 301a through <NUM> may constitute half of the transducer elements in the transducer array <NUM>. A second portion (e.g., a second half) of transducer columns <NUM> or transducer elements in the transducer array <NUM> are depicted to the right of column <NUM>. In various embodiments, configurations of transducer elements need not be limited to half of the array, but could be divided into sections or groups corresponding to one third, one fourth, two thirds, or any other partial fraction or suitable arrangement or configuration. Column <NUM> may represent the first transducer column <NUM> corresponding to the second portion of transducer columns <NUM>. Adjacent and to the right of column <NUM> may be an additional column 301n followed by column 301o, and so on as indicated by the second set of ellipses. Such transducer elements may therefore continue until transducer column 301z at the rightmost end of the transducer array <NUM>. Although numerals 301a through 301z have been used to indicate the columns of transducer elements <NUM> shown in <FIG>, the transducer array <NUM> shown in <FIG> need not contain <NUM> columns of transducer elements <NUM>. Rather, and as previously stated, the transducer array <NUM> can include any suitable number of rows and/or columns.

In some embodiments, an ultrasound image is generated from a series of acoustic lines or A-lines, with each line formed by a set of array elements translating across the aperture. For example, the first line may use a set of elements <NUM>, the second using a set of elements <NUM>, and so on with the last using a set <NUM>.

During an ultrasound examination, the ultrasound imaging system <NUM> may designate a set of the transducer elements <NUM> to transmit ultrasound signals such that ultrasound energy propagates into an anatomy of a patient. The ultrasound imaging system <NUM> may further specify a set of transducer elements <NUM> to receive reflected waves. In some embodiments, the ultrasound transducers <NUM> selected to transmit ultrasound signals may be the same transducers used to receive reflected waves. In other embodiments, the ultrasound transducer elements <NUM> used to transmit ultrasound signals are different elements from those that receive. For example, in some embodiments, the ultrasound imaging system may select half of the ultrasound transducer elements <NUM> to transmit ultrasound signals into a patient's anatomy. As shown in <FIG> by boxes <NUM>, <NUM>, and <NUM>, these elements selected for signal transmission may be any transducer elements. In some embodiments, the transducer elements may all be adjacent to one another. For example, box <NUM> of <FIG> indicates that the transducer elements <NUM> of columns 301a to <NUM> are selected by the ultrasound imaging system <NUM> to transmit ultrasound signals into an anatomy and form the aperture of the transducer array <NUM>. The ultrasound imaging system <NUM> may shift the aperture, through adjustments in the circuitry of analog processors <NUM> as will be discussed later, such that the aperture is defined by columns 301b through <NUM> as shown by box <NUM>. The aperture can be further shifted to include columns 301c through 301n, columns 301d through 301o, and so on, until, as shown by box <NUM>, the aperture can be configured as columns <NUM> through 301z. In some embodiments, the transducer elements <NUM> selected to transmit ultrasound signals need not be directly adjacent to one another but may be spaced by one or more transducer elements <NUM> not used to transmit ultrasound signals. As the boxes <NUM>, <NUM>, and <NUM> identify elements of the transducer array <NUM> which together form an aperture, the boxes <NUM>, <NUM>, and <NUM> may additionally be referred to as apertures.

As shown in <FIG>, the transducer elements of the transducer array <NUM> are in communication with a plurality of circuits <NUM> via multiple conductors <NUM>. The conductors <NUM> may electrically couple the transducer elements <NUM> of the transducer array <NUM> to the circuits <NUM>. The conductors <NUM> may be of any suitable form or type. In some embodiments, the conductors <NUM> may include conductive pathways or conductive traces positioned on a printed circuit board (PCB), a flexible or inflexible substrate, or in any other suitable configuration. As shown in <FIG>, each circuit <NUM> is in communication with six transducer elements <NUM> via four conductors <NUM>. Specifically, as shown in <FIG>, the outer transducer elements 305a of column 301a may be electrically coupled to one another and a circuit <NUM> via conductor <NUM>. The inner element 305b may be in communication with the same circuit <NUM> via conductor <NUM>. The outer elements 305a of column <NUM> may be coupled to one another and the same circuit <NUM> via conductor <NUM>. And finally, the inner element 305b of column <NUM> may be in communication with the same circuit <NUM> via conductor <NUM>. The next circuit <NUM> may be in communication with the inner elements 305b and outer elements 305a of columns 301b and 301n in a similar manner. The next circuit <NUM> may be in communication with the elements of columns 301c and 301o in a similar manner and so on such that all transducer elements <NUM> are in communication with a respective circuit <NUM>.

In other embodiments, a circuit <NUM> may be in communication with more or fewer transducer elements <NUM>. For example, in an embodiment with five transducer rows, a circuit <NUM> may still be in communication with two transducer columns <NUM> as described, but each column may include five transducer elements. In such an embodiment, the outermost elements may be coupled together and to an analog processor <NUM> via one conductor <NUM>, an additional conductor <NUM> may couple the elements between the outermost elements and the innermost element and to the same circuit <NUM>, and an additional conductor <NUM> may provide communication between the innermost element and the circuit <NUM>. In such an embodiment, rather than four conductors <NUM> in communication with the circuit <NUM>, six such conductors <NUM> may be in communication with the circuit <NUM>. Additional rows of transducer elements <NUM> would require additional conductors <NUM> as can be extrapolated. In addition, other embodiments involve one or more circuits <NUM> in communication with more than four transducer columns <NUM>. These embodiments would require additional changes to the circuitry of analog processors <NUM> according to the embodiments described as will be outlined and discussed hereafter.

As described in more detail herein, the circuits <NUM> can include an analog to digital converter (ADC) such that the output of the circuits <NUM> is digital data or a bitstream. As shown by numerals <NUM>, in some embodiments, the output of the circuits <NUM> may be a <NUM>-bit output. However, the output of the circuits <NUM> may have any suitable bitrate (e.g., <NUM>-bit, <NUM>-bit, <NUM>-bit, <NUM>-bit, <NUM>-bit, <NUM>-bit, or any suitable number less than, greater than, or between those listed).

The circuits <NUM> may be in communication with a combiner <NUM>. The combiner <NUM> is representative of circuitry that can reduce the total signal lines received from the circuits <NUM> and reduce the number of required signal lines for transmitting data to the host <NUM>. The combiner <NUM> may reduce the number of signal lines by any suitable method. In some embodiments, the combiner <NUM> may include a summing node. The combiner <NUM>, as well as any other suitable component or circuitry within the system <NUM> may include features similar to those described in <CIT> (corresponding to <CIT>), titled "ULTRASOUND PROBE WITH MULTILINE DIGITAL MICROBEAMFORMER," and/or<CIT>(claiming priority from<CIT>). In some embodiments, the combiner <NUM> may be a multiplexer that multiplexes data received from the circuits <NUM> into high-speed serial links and then sends the data to the host <NUM> to be processed. In some embodiments, the combiner <NUM> may be a digital beamformer that performs a second stage of beamforming (delaying and summing of signals) after the first stage of beamforming is completed by an optional analog beamformer.

The combiner <NUM> may be in communication with the serializer and high-speed current mode logic (CML) <NUM>. The serializer/CML <NUM> may rearrange lines received from the combiner <NUM> and/or the circuits <NUM> into a high-rate serial data stream. In some embodiments, the serializer/CML <NUM> may run at a higher data rate than other circuitry within the probe <NUM>. For example, the serial data stream may run at <NUM>, whereas other circuitry within the ultrasound signal path may run at <NUM>. The serializer/CML <NUM> may operate in a similar manner to the serializer disclosed in <CIT>. Accordingly, in one of the signals paths of the probe <NUM>, digital ultrasound data (e.g., B-mode data) can be transmitted from the probe <NUM> to the host <NUM> via the conductors <NUM>. The conductors <NUM> may be a twisted pair of conductors or any other suitable form of conductors.

As previously mentioned, the probe <NUM> may be in communication with the host <NUM> via a communication interface or link <NUM> of <FIG>. The link <NUM> may have any suitable number or types of conductors but may include the power and/or control conductors(s) <NUM> and one or more transducer conductors <NUM>.

The power and/or control communication line(s) <NUM> may include one or multiple signal and/or power lines including conductors, twisted pairs, or any other suitable means of transferring data, signals, or power. For example, the communication line(s) <NUM> may include a conductor dedicated to providing control signals or other data from the host <NUM> to the probe <NUM>. The conductors <NUM> may further include conductors that provide necessary power from the host <NUM> to components within the probe <NUM>. The signal conductors may be in communication with a controller or any other suitable component within the host <NUM> and may provide signals for controlling clocks mentioned previously, switches, pulsers, the transducer array <NUM>, the circuits <NUM>, the combiner <NUM>, the serializer/CML <NUM>, and/or any other component within the probe <NUM>. In some embodiments, the signal carrying conductor(s) of conductors <NUM> may be a twisted pair. In other embodiments, they may be a single conductor or any other suitable means of transmitting data signals. In some embodiments data transmitted via the conductors <NUM> may be <NUM> Mbs data, or data of any suitable frequency or type. The conductors <NUM> may further include a power line which may be in communication with a power supply within the host <NUM> or at any suitable location. The conductors <NUM> may provide DC or AC electrical signal to various components within the probe <NUM>.

Further connecting the probe <NUM> and the host <NUM> may be multiple signal lines <NUM>. The transducer lines or conductors <NUM> may correspond to a reduced number of signal lines output from the serializer/CML <NUM>. In some embodiments, the transducer lines <NUM> may include only a single signal line. In other embodiments, the transducer lines <NUM> may include multiple signal lines. In some embodiments, the transducer lines <NUM> may be twisted pairs. In other embodiments, they may be single conductors, coaxial conductors, or any other suitable communication pathway for transmitting data signals. In addition, in some embodiments, the transducer conductors <NUM> may carry analog signals. In other embodiments, the conductors <NUM> may carry digital signals. In some embodiments, the signals may be carried over an optical link. In some embodiments, the signals may be carried wirelessly.

The conductors <NUM> and the transducer lines <NUM> may together form one connecting cable similar to the connecting cable <NUM> described with reference to <FIG>. Specifically, the conductors <NUM> and the transducer lines <NUM> may be wrapped together with a cable shielding. The conductors <NUM>, the transducer conductors <NUM>, and any corresponding conductors enclosed together may be of any suitable length and/or may be a flexible elongate member. For example, the conductors <NUM>, the transducer lines <NUM>, and all associated conductors may be <NUM> meter, <NUM> meters, <NUM> meters in length, or other suitable values, both larger, smaller, or therebetween. In other embodiments, the conductors <NUM> and the transducer lines <NUM> may form separate connecting cables of the same or varying lengths.

The host <NUM> depicted in <FIG> and previously described with reference to <FIG> may include any suitable circuitry or may be of any suitable form. For example, the host <NUM> may include circuits such as integrated circuits, field-programmable gate arrays (FPGAs), processors, mixers, power supplies, controllers, filters, op-amps, or any other suitable circuitry configured to perform various functions related to beamforming, filtering, processing, ultrasound image generation, and/or displaying ultrasound images or data.

<FIG> is a plot <NUM> illustrating example gain profiles applied to electrical signals generated by the transducer elements <NUM> of the transducer array <NUM>, according to aspects of the present disclosure. The gain profiles depicted in plot <NUM> may be applied to the signals received from the various transducer elements <NUM> improving image or data quality corresponding to structures within an anatomy at various locations or depths with relation to the probe <NUM>. Components shown in <FIG> may be communicatively and/or electrically positioned on signal paths, signal pathways, electrical paths, electrical pathways, or any other suitable terms.

The plot <NUM> includes a vertical axis <NUM> and a horizontal axis <NUM>. Five locations, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> are included along the horizontal axis <NUM>. The plot <NUM> further includes an inner element gain profile <NUM>, an outer element gain profile <NUM>, and a weighted gain profile <NUM>.

The vertical axis <NUM>, as labelled in <FIG>, corresponds to the gain applied to electrical signals generated by one or more transducer elements <NUM> within the transducer array <NUM>. A point within the plot <NUM> at a lower position along the vertical axis <NUM> corresponds to a lower gain value applied to the electrical signals. By contrast, a point corresponding to a higher location along the vertical axis <NUM> corresponds to a higher gain value applied to the electrical signals. The ratio of gain between low gain and high gain may be in the range of 10dB to 60dB or any other suitable range. For example, low gain may be -20dB and high gain may be +20dB.

The horizontal axis <NUM>, as labelled in <FIG>, corresponds to the depth of an anatomical object within an anatomy. In some cases, the depth of an anatomical object may correspond to the distance of the object from the transducer array <NUM>. This depth or distance may, in some applications, be determined by measuring the amount of time from when ultrasound energy is emitted from the probe <NUM> to the reception of reflected waves or echoes at the probe <NUM>. In such an application, the depth of an anatomical object measured may also be referred to in terms of, or in units of, time. <FIG> labels the horizontal axis <NUM> both as a measurement of depth and/or time. A point to the left of the plot <NUM> or a lower value along the horizontal axis <NUM> corresponds to a shallower depth, or a smaller distance from an anatomical object to the transducer array <NUM>. For example, the time between transmission of an ultrasound signal and reception of a reflection is shorter for anatomy that is closer to the array <NUM> and less deep within the patient body. By contrast, a point to the right of the plot <NUM>, or a higher value along the horizontal axis <NUM>, corresponds to a deeper depth. For example, the time between transmission of an ultrasound signal and reception of a reflection is greater for anatomy that is farther away from the array <NUM> and deeper within the patient body. The locations <NUM>, <NUM>, <NUM>, <NUM>, <NUM> designate various depths or times in relation to the gain profiles <NUM>, <NUM>, and/or <NUM>. In an example, the location <NUM> may correspond to <NUM> or <NUM>, the location <NUM> may correspond to <NUM> or <NUM>, the location <NUM> may correspond to <NUM> or <NUM>, the location <NUM> may correspond to <NUM> or <NUM>, and the location <NUM> may correspond to <NUM> or <NUM>. In other examples, the locations <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> may correspond to any suitable depth or time measurement appropriate for the particular application.

The gain profiles <NUM>, <NUM>, and <NUM> illustrate how the gain applied to signals received from the outer elements 305a may be increased as depth or time increases effectively increasing the elevational size of the aperture. This increase in size of the aperture increases the magnitude of the received signals accounting for increased attenuation associated with increased depth resulting in better image quality in the far field. The gain profiles <NUM> and <NUM> together are associated with one method of increasing the elevational size of the aperture. The gain profiles <NUM> and <NUM> together are associated with another method of increasing elevational width of the aperture. In the near field of the image, a small aperture is used to produce an acoustic beam with a small width in elevation producing good detail and contrast resolution. However, this small aperture has insufficient energy to see deep within the body. To achieve the desired penetration in the far field, all the elements in the elevation aperture are used.

In some embodiments, the gain profiles <NUM>, <NUM> can be used respectively to apply separate gain profiles for electrical signals of the inner elements 305b and outer elements 305a. The gain profile <NUM> shown in the plot <NUM> may represent a gain profile applied to inner elements 305b within the transducer array <NUM>. At a point <NUM> along the horizontal depth/time axis <NUM> representing a location close to the transducer array <NUM>, the gain applied to signals received from the inner elements 305b is low or of reduced amplitude. The gain applied to signals received from the outer elements 305a as shown by the gain profile <NUM> may, at location <NUM>, be zero because the outer elements 305a may not be needed to receive echoes from a shallow location <NUM>.

As the depth and/or time increases from point <NUM> to point <NUM> along the horizontal depth/time axis <NUM>, the gain applied to signals received from the inner elements 305b gradually increases as shown by the gain profile <NUM> shown in <FIG>. At a point between points <NUM> and <NUM>, the gain applied to signals received from the outer elements 305a may remain zero. Between points <NUM> and <NUM>, therefore, the elevational size of the aperture remains unchanged, but the gain applied to the electrical signals generated by the inner elements 305b increases to account for attenuation caused by ultrasound waves travelling a greater distance through the medium of a patient's anatomy.

At the point <NUM>, as the gain profile <NUM> applied to inner elements 305b approaches a maximum, a small amount of gain is applied to signals received from the outer elements 305a as shown by the gain profile <NUM>. At the point <NUM>, the gain applied to signals from the inner elements 305b may be significantly greater than the gain applied to signals from the outer elements 305a as illustrated in the plot <NUM>. The reduced gain applied to signals from the outer elements 305a may serve to gradually expand in elevation the aperture of the transducer array <NUM>. The gain applied to signals from the outer elements 305a increases the effect of the echo signals received by the outer elements 305a on the ultrasound data, which corresponds to the emitted ultrasound imaging beam propagating deeper and wider into the anatomy.

At the point <NUM>, the gain profile <NUM> applied to signals received from the inner elements 305b may be substantially at a maximum. In addition, as shown by the gain profile <NUM>, the gain applied to signals received from the outer elements 305a may be significantly increased which in turn increases the elevational width of the aperture. This widening of the aperture may subsequently account for attenuation caused by ultrasound echoes travelling through the anatomy from a location of increased depth and enhance the quality of received data or constructed ultrasound images. At the point <NUM>, both the gain profile <NUM> and the gain profile <NUM> applied to the inner elements 305b and the outer elements 305a respectively may be at a maximum.

The plot <NUM> additionally illustrates an alternative method of implementing separate gain profiles to signals received from the inner elements 305b and signals received from the outer elements 305a such that the elevation dimension of the aperture may be increased with depth or time. In some embodiments, and as will be discussed in more detail with reference to <FIG>, an identical gain profile may be applied to both signals received from the inner elements 305b and signals received from the outer elements 305a. This gain profile may be of similar characteristics as the gain profile <NUM> shown in <FIG> or may differ. For example, the gain profile applied to both the inner elements 305b and the outer elements 305a may increase the gain with depth to account for attenuation from travelling deeper through the patient's anatomy. Rather than applying a separate gain profile to signals received from the outer elements 305a to increase the elevational width of the aperture with depth, a gain profile <NUM> may be additionally applied to the outer elements 305a such that at a small depth where an imaged anatomical object is positioned close to the transducer array <NUM>, there is effectively no influence from the signals received from the outer elements 305a. For example, when the signals from inner elements 305b with the signals from outer elements 305a, at shallower depths, the signal component received from the inner elements 305b contributes significantly more to the summed signal than the signal component from the outer elements 305a. As depth increases, however, as shown by the gain profile <NUM>, the outer elements 305a are gradually engaged allowing the common gain profile similar to the gain profile <NUM> to be fully applied. This gradually increases the elevational width of the aperture. As shown in <FIG>, at all points of depth to the left of point <NUM>, the gain profile <NUM> may suppress all gain applied to signals from the outer elements <NUM>. Between points <NUM> and <NUM>, however, the gain profile <NUM> may gradually allow increasing gain to signals from the outer elements 305a thus increasing the elevational dimension of the aperture. At all points to the right of point <NUM>, the gain profile <NUM> may allow full gain to the outer elements 305a such that the elevational width of the aperture is at a maximum. The gain profile <NUM> may additionally be referred to as a weighting profile because it is selectively applied to the electrical signals generated by the outer elements 305a so that the effect of these electrical signals changes based on the profile <NUM>.

It is noted that the gain profiles disclosed in <FIG> and described herein are merely example gain profiles and any number of different gain profiles may be generated and applied to the inner elements 305b and/or the outer elements 305a. For example, various gain profiles may begin a gradual gain increase to transducer elements sooner or beginning at a closer distance of an anatomical object to the transducer array <NUM>. In other embodiments, the gain may begin increasing at a greater depth. In still other embodiments, the rate of increase of gain for each of the disclosed gain profiles may be greater or less or may involve different, varying, or inconsistent rates of increasing gain as depth increases along the horizontal axis <NUM>.

<FIG> is a schematic diagram illustrating example circuitry in communication with the transducer array <NUM>, according to aspects of the present disclosure. <FIG> provides a more detailed view of one embodiment of the circuitry within one of the circuits <NUM>.

The circuit <NUM> depicted in <FIG> may include four input conductors including conductors <NUM>, <NUM>, <NUM>, and <NUM>. Each of these four conductors may be coupled to a transmit receive switch (T/R switch) <NUM>. Each T/R switch <NUM> may be additionally coupled to a pulser <NUM> and a preamp <NUM>. Preamps <NUM> may be coupled to a summation component <NUM>. Each summation component <NUM> may be coupled to an aperture translation multiplexer (MUX) <NUM> which may be coupled to an analog-to-digital converter <NUM>. The MUX <NUM> can operate as a switch. In some embodiments, the MUX <NUM> can be a switch. The ADC <NUM> can be a low power ADC in some embodiments.

Conductor <NUM> shown in <FIG> connects the inner element 305b of column 301a (<FIG>) to a T/R switch <NUM>. Similarly, conductor <NUM> connects the outer elements 305a of column 301a to an additional T/R switch <NUM>, conductor <NUM> connects the inner element 305b of column <NUM> to a T/R switch, and connector <NUM> connects the outer elements 305a of column <NUM> to a final T/R switch <NUM> shown in <FIG>.

T/R switches <NUM> may be configured to switch between transmit and receive signal paths. For example, in a transmit position, the T/R switch <NUM> may receive a signal from the pulser <NUM> and subsequently transmit the signal to the transducer array <NUM> to energize the array to emit ultrasound energy. The pulsers <NUM> may also be referred to as transmit pulsers. The pulsers <NUM> may receive a transmit signal generated by the host <NUM>. The pulsers <NUM> may be in communication with the host <NUM> via conductors <NUM>. For example, the pulsers <NUM> may be in communication with the host via an <NUM> Mbs data conductor or any other suitable conductor or cable. In other embodiments, the pulsers <NUM> may also be configured to output electrical excitation pulses timed to excite the elements of the transducer array <NUM> to produce an acoustic transmit wave-front. The pulser circuitry may be located within the transducer housing.

In receive position, the T/R switch <NUM> may receive signals corresponding to reflected waves received by the transducer array <NUM> and transmit them to the preamp <NUM>. T/R switches <NUM> may additionally be in communication with the host <NUM> via an <NUM> Mbs data line or any suitable conductor cable and may receive instructions regarding switching between transmit and receive signal paths. This communication cable may be included in the communication cable or link <NUM> of <FIG> and/or cable <NUM> of <FIG>.

The preamplifiers <NUM> may be in communication with the output of the T/R switches <NUM> as shown in <FIG> and may be in communication with the elements of the transducer array <NUM> via the T/R switches <NUM>. Specifically, when a T/R switch <NUM> is set in a receiving configuration by the ultrasound system <NUM>, received signals corresponding to reflected waves may be transmitted to a connected preamp <NUM> through the T/R switch <NUM>. In some embodiments, the number of pulsers <NUM> may be equal to the number of preamps <NUM> and the number of T/R switches <NUM>. For example, each T/R switch <NUM> may be configured to receive data from one pulser <NUM> and transmit data from the transducer array <NUM> to one preamp <NUM>. The preamps <NUM> may amplify signals received from the T/R switches <NUM> so as to improve the quality of received signals by, for example, reducing a noise floor. The outputs of the preamplifiers <NUM> may additionally be in communication with the summation components <NUM>.

In addition to amplifying signals received from the outputs of the T/R switches <NUM>, the preamps <NUM> may also implement the gain profiles <NUM> or <NUM> discussed with reference to <FIG>. For example, the preamps <NUM> in communication with conductors <NUM> and <NUM> receiving signals from the inner transducer elements 305b may implement the gain profile <NUM> to received signals. By contrast, the preamps <NUM> in communication with the conductors <NUM> and <NUM> receiving signals from the outer elements 305a may implement the gain profile <NUM> to received signals. Signals on which gain is applied may be called gain-adjusted signals.

Various methods of implementing the gain profiles <NUM> and <NUM> may be employed. In some embodiments, a programmable resistor may be implemented in communication with the preamps <NUM> in communication with the conductors <NUM> and <NUM> corresponding to the inner elements 305b. A separate programmable resistor may then also be implemented in communication with the preamps <NUM> in communication with the conductors <NUM> and <NUM> corresponding to the outer elements 305a. The programmable resistors may include a bank of resistors controlled with a sweeping control that may select from a number of different resistor selections. In some embodiments, the programmable resistors may include <NUM> different resistor selections. In other embodiments, the programmable resistors may include more or less resistor selections, such as two, four, eight, ten, <NUM>, <NUM>, <NUM>, <NUM>, or any suitable number greater than, less than, or between those listed. The sweeping control which selects different resistor selections may digitally control the programmable resistors according to the gain profiles <NUM> or <NUM> depending on which preamps <NUM> are being controlled. In some embodiments, two programmable resistors may be implemented in the probe <NUM>. Each programmable resistor may control several of the preamps <NUM>. In other embodiments, additional programmable resistors may be implemented.

At a summation component <NUM>, signals received from the inner transducer elements 305b via the conductor <NUM> and the outer elements 305a via the conductor <NUM> are combined in an analog fashion and transmitted to the aperture translation MUX <NUM>. Signals from the inner elements 305b via the conductor <NUM> and the outer elements 305a via the conductor <NUM> are similarly combined with a summation component <NUM> as well, as shown in <FIG>. The summation components <NUM> may additionally be an analog adder circuit, summing mixer, or any suitable electronic component for summing signals.

The aperture translation MUX <NUM> shown in <FIG> may shift the aperture in the lateral/azimuth dimension as shown by the axis <NUM> in <FIG> along the transducer array <NUM> by switching between different positions. The aperture translation MUX <NUM> may additionally be referred to as a switch. For example, as discussed previously, in some embodiments, half (or any other suitable fraction, arrangement, or configuration) of the transducers <NUM> of the transducer array <NUM> may be used to transmit and receive ultrasound imaging signals into an anatomy thus forming the aperture of the transducer array <NUM>. As the conductors <NUM> and <NUM> provide signals to and from the transducer column 301a and the conductors <NUM> and <NUM> provide signals to and from the transducer column <NUM>, the aperture translation MUX <NUM> shown in <FIG> may switch between these two columns, column 301a and column <NUM>. In this way, either column 301a or column <NUM> is engaged at once. Referring back to <FIG>, the ultrasound imaging system <NUM> may define the aperture <NUM> as transducer columns 301a through <NUM>. In such a configuration, the aperture translation MUX <NUM> within the analog processor <NUM> in communication with column 301a and <NUM> would be switched to engage column 301a and not <NUM>. Similarly, the aperture translation MUX <NUM> in communication with columns 301b and 301n would be switched to engage column 301b, and not column 301n, and so on. Lastly, the aperture translation MUX <NUM> in communication with column <NUM> and 301z would be switched to engage column <NUM>, and not 301z. If the ultrasound imaging system <NUM> were to shift the aperture to the right (aperture <NUM>) by one transducer element <NUM>, the only change necessary would be for the aperture translation MUX <NUM> in communication with column 301a and <NUM> to switch to engage column <NUM>. Similarly, for the ultrasound imaging system <NUM> to move the aperture to the aperture <NUM>, each aperture translation MUX <NUM> would switch to engage the other column <NUM>. In this manner, the aperture can be shifted to any suitable location using any suitable transducer columns <NUM> within the transducer array <NUM>. Imaging data from each aperture in the azimuthal or lateral direction can be used to form one or more A-lines of a B-mode image. The A-lines generated from data obtained by multiple apertures can be combined to generate a B-mode image.

The output of the aperture translation MUX <NUM> shown in <FIG> is in communication with an ADC <NUM>. The ADC <NUM> may be configured to convert analog ultrasound echo signals into digital ultrasound echo signals. For example, the ADC <NUM> may receive analog ultrasound echo signals generated by a given aperture of the transducer array <NUM>, transmitted to the preamps <NUM> via the T/R switches <NUM> and convert them into digital ultrasound echo signals. Digital ultrasound echo signals may include digital samples representing the waveforms of corresponding analog ultrasound echo signals. The ADC <NUM> may employ a successive approximation ADC architecture to provide high-performance and lower-power consumption, and thus may keep total power dissipation of the probe <NUM> to be within a thermal budget of the probe <NUM>. However, any suitable ADC architecture may be used for the ADC <NUM>.

Numeral <NUM>, shown in <FIG> was mentioned previously with reference to <FIG>, and represents the bitrate of the ADC <NUM> and more generally the bitrate of the output of the analog circuitry <NUM>. Groups of components shown in <FIG> may together be referred to as signal paths, signal pathways, electrical paths, electrical pathways, or any other suitable terms. For example, the conductor <NUM> in communication with a T/R switch <NUM>, and a preamp <NUM> may be referred to as a signal path, or an inner element signal path. Any other groupings of components within <FIG> may additionally be referred to as signal paths and are also contemplated.

<FIG> is a schematic diagram illustrating example circuitry in communication with the transducer array <NUM>, according to aspects of the present disclosure. All of the components shown in <FIG> may be substantially similar to those depicted in <FIG>. However, the circuit <NUM> shown in <FIG> additionally includes a weight component <NUM>. In that regard, the weight component <NUM> is an additional amplifier in the signal path of the analog ultrasound signals from the outer elements 305a of the transducer array <NUM>. Accordingly, the weight component <NUM> can be referred to as a weight amplifier. Groups of components shown in <FIG> may similarly be referred to as signal paths, signal pathways, electrical paths, electrical pathways, or any other suitable terms.

The weight component <NUM> is in communication with the output of the preamps <NUM> which are in communication with the outer elements 305a via the conductors <NUM> and <NUM>. The embodiment illustrated in <FIG> may correspond to the gain profile <NUM>. Specifically, in the embodiment shown in <FIG>, a common gain profile is applied to the preamps <NUM> for both the inner elements 305b and the outer elements 305a, as previously mentioned. In some of these embodiments, all the preamps <NUM> may be in communication with a common programmable resistor. The programmable resistor may be very similar to the programmable resistor described with reference to <FIG>. For example, the programmable resistor may step through a series of resistor selections to implement a gain profile similar to the gain profiles disclosed in <FIG>. The common gain profile may be similar to the gain profile <NUM> described with reference to <FIG>. The weight component <NUM> then applies an additional gain profile, similar to the gain profile <NUM> described with reference to <FIG>, to the signals received from the outer transducer elements 305a via the conductors <NUM> and <NUM>. As previously described, the gain profile <NUM> may additionally be referred to as a weighting profile and is selectively applied to the electrical signals generated by the outer elements 305a so that the effect of these electrical signals changes based on the profile <NUM>. This selective application is accomplished by the positioning of the weight components <NUM> only in signal paths in communication with the outer elements 305a. In some embodiments, the weight component <NUM> may also be a programmable resistor with a set of resistor selections that can implement the gain profile or weighting profile <NUM> of <FIG> in a similar way. However, the programmable resistor implemented to control the weight component <NUM> may include far fewer resistor selections than the programmable resistor implementing a common gain profile for all preamps <NUM>. In this way, the outer elements 305a may still be gradually engaged to widen the elevational width of the aperture, but fewer components are needed. The result is a simpler, less expensive, and more compact circuitry within the probe <NUM>. It is also noted that any suitable method of implementing gain profiles <NUM>, <NUM>, and/or <NUM>, or any other suitable gain profile may be used within the circuits <NUM>. In some embodiments, the weight component <NUM> may be a variable gain amplifier which further acts on the signals received from the outer elements 305a previously acted on by the preamp <NUM> according to an additional gain profile similar to the gain profile <NUM> of <FIG>. The variable gain amplifier <NUM> can be configured to amplify or attenuate the input signals.

<FIG> is a schematic diagram illustrating example circuitry in communication with the transducer array <NUM>, according to aspects of the present disclosure. <FIG> illustrates an additional embodiment of the present disclosure. All of the components shown in <FIG> may be substantially similar to those depicted in <FIG> and/or <FIG>. However, the circuit <NUM> shown in <FIG> may additionally include multiple ADCs <NUM>, delay components <NUM>, and ADC clock controls <NUM>. Groups of components shown in <FIG> may similarly be referred to as signal paths, signal pathways, electrical paths, electrical pathways, or any other suitable terms. In addition, components positioned after the ADCs <NUM> in <FIG> may be digital implementations of the components of <FIG> and <FIG>. For example, the weighting component or amplifier <NUM> shown in <FIG> may be a digital weight component or amplifier.

In the embodiment shown in <FIG>, analog signals received from the transducer array <NUM> may be converted to digital signals before the weighting profile <NUM> is applied by the weight components <NUM>. An ADC <NUM> may be positioned in communication with the output of the preamps <NUM>. Similar to the ADC <NUM> of <FIG> and <FIG>, the ADCs <NUM> may be configured to convert analog ultrasound echo signals into digital ultrasound echo signals. The ADCs <NUM> may be substantially similar to the ADC <NUM> in that they may use a successive approximation ADC architecture or may be of any other suitable type of ADC. The ADCs <NUM> may have any of the characteristics or features of the ADC <NUM>.

Delay components <NUM> may be in communication with the output of the ADC's <NUM>. The delay components <NUM> may include hardware components, software components, or a combination of hardware and software components. A primary purpose of the delay components <NUM> may be to focus the ultrasound imaging beam to produce a narrower beam than can be achieved using aperture width control alone. This enhanced focus is achieved by delaying the signals so that they are time aligned to sum coherently. For example, the delay components <NUM> may apply a delay to signals received from the inner transducer elements 305b and/or the outer elements 305a to control the location of the focus of the ultrasound imaging beam in the elevation dimension. In an example, the delay components <NUM> may receive commands from the host <NUM> to delay the received signals from the outer elements 305a by a specified amount of time. The delay may correspond to a number of samples. In an example, the delay components <NUM> may receive ultrasound data from the ADC's <NUM> and transmit the data to the summation components <NUM> or the weighting components <NUM>, depending on the signal path, after delaying the data by the amount of time of one sample. The delay components <NUM> may delay the data by any suitable number of samples. In an embodiment in which ultrasound echo signals from the outer elements 305a are delays, as the delay to outer elements 305a is increased the focus of the imaged data may move closer to the ultrasound transducer array <NUM> and vice versa. The delay components <NUM> may be implemented using memory elements or a shift register. Fine delay control can be achieved by adjusting the sampling phase of the ADC. In other embodiments, an additional purpose of the delay components <NUM> may be to perform beamforming to signals received from the transducer elements <NUM>. The delay components <NUM> may therefore be used to apply delays to signals between transducer elements in either the elevational direction, or the azimuthal direction, or both. In some embodiments, beamforming in the azimuthal dimension may occur for partial sets of elements or sub-arrays such as element pairs. This partial beamforming may reduce the amount of data sent to the system. For example, beamforming pairs of elements halves the data sent to the system thereby halving the associated number of wires. As partial beamforming is performed on sets of more elements, the data sent to the system and associated wires is further decreased.

Claim 1:
An ultrasound imaging system (<NUM>), comprising:
an ultrasound probe (<NUM>), comprising:
a housing (<NUM>);
a <NUM>.X-dimensional transducer array (<NUM>) mechanically coupled to the housing, wherein the transducer array comprises;
a first row of acoustic elements (305b),
a second row of acoustic elements (305a), and
a third row of acoustic elements (305a),
wherein the first row of acoustic elements is arranged between the second row of acoustic elements and the third row of acoustic elements in an elevation dimension, and
wherein the first row of acoustic elements comprises a first acoustic element, the second row of acoustic elements comprises a second acoustic element, and the third row of acoustic elements comprises a third acoustic element,
wherein the first acoustic element is arranged between the second acoustic element and the third acoustic element in an elevation dimension, and
wherein the first acoustic element is configured to generate a first analog ultrasound signal, and the second acoustic element and the third acoustic element are electrically coupled to generate a second analog ultrasound signal;
a first amplifier (<NUM>) disposed within the housing and in communication with the first acoustic element; and
a second amplifier (<NUM>) disposed within the housing and in communication with the second acoustic element and the third acoustic element, and characterized by:
a third amplifier (<NUM>) disposed within the housing and in communication with the second acoustic element and the third acoustic element,
wherein the first amplifier and the second amplifier are configured to apply gain to the first analog ultrasound signal and the second analog ultrasound signal, respectively, according to a first gain profile, and
wherein the third amplifier is configured to apply additional gain only to the second analog ultrasound signal according to a second gain (<NUM>, <NUM>, <NUM>) profile that is different from the first gain profile,
wherein the second gain profile increases as the imaging depth increases thereby increasing an elevational size of an aperture of the transducer array.