Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
  • G01S7/52023—Details of receivers
  • G01S7/52025—Details of receivers for pulse systems
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
  • A61B8/4427—Device being portable or laptop-like
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
  • A61B8/4483—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device characterised by features of the ultrasound transducer
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/54—Control of the diagnostic device
  • A61B8/546—Control of the diagnostic device involving monitoring or regulation of device temperature
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/56—Details of data transmission or power supply
  • A61B8/565—Details of data transmission or power supply involving data transmission via a network
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/88—Sonar systems specially adapted for specific applications
  • G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
  • G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
  • G01S15/8909—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration
  • G01S15/8915—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration using a transducer array
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/88—Sonar systems specially adapted for specific applications
  • G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
  • G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
  • G01S15/899—Combination of imaging systems with ancillary equipment
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
  • G01S7/52079—Constructional features
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
  • G01S7/52079—Constructional features
  • G01S7/5208—Constructional features with integration of processing functions inside probe or scanhead
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
  • A61B8/4444—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device related to the probe
  • A61B8/4472—Wireless probes
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/56—Details of data transmission or power supply
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/58—Testing, adjusting or calibrating the diagnostic device
  • A61B8/582—Remote testing of the device
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
  • A61B8/58—Testing, adjusting or calibrating the diagnostic device
  • A61B8/585—Automatic set-up of the device
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
  • G01S15/88—Sonar systems specially adapted for specific applications
  • G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
  • G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
  • G01S15/8979—Combined Doppler and pulse-echo imaging systems
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
  • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
  • G01S7/52053—Display arrangements
  • G01S7/52055—Display arrangements in association with ancillary recording equipment

Definitions

• Conventional ultrasound imaging systems typically include a handheld probe coupled by cables to a large rack-mounted console processing and display unit.
• the probe typically includes an array of ultrasonic transducers which transmit ultrasonic energy into a region being examined and receive reflected ultrasonic energy returning from the region.
• the transducers convert the received ultrasonic energy into low-level electrical signals which are transferred over the cable to the processing unit.
• the processing unit applies appropriate beam forming techniques to combine the signals from the transducers to generate an image of the region of interest.
• Typical conventional ultrasound systems include a transducer array each transducer being associated with its own processing circuitry located in the console processing unit.
• the processing circuitry typically includes driver circuits which, in the transmit mode, send precisely timed drive pulses to the transducer to initiate transmission of the ultrasonic signal. These transmit timing pulses are forwarded from the console processing unit along the cable to the scan head.
• beamforming circuits of the processing circuitry introduce the appropriate delay into each low-level electrical signal from the transducers to dynamically focus the signals such that an accurate image can subsequently be generated.
• control circuitry and beamforming circuitry are localized in a portable assembly. Such an integrated package simplifies the cable requirements of the assembly, without adding significant weight.
• a user may gather ultrasonic data on a standard user computing device such as a PC, and employ the data so gathered via an independent external application without requiring a custom system, expensive hardware modifications, or system
• a system and method for gathering ultrasonic data on a standard user computing device and employing the data via an integrated interface program allows such ultrasonic data to be invoked by a variety of external applications having access to the integrated interface program via a standard
• predetermined platform such as visual basic or C++.
• the system provides external application integration in an ultrasonic imaging system by defining an ultrasonic application server for performing ultrasonic operations.
• An integrated interface program with a plurality of entry points into the ultrasonic application server is defined.
• the entry points 5 are operable to access each of the ultrasonic operations.
• An external application sends a command indicative of at least one of the ultrasonic operations.
• the command is transmitted via the integrated interface program to the ultrasonic application server.
• raw ultrasonic data indicative of ultrasonic image information is received by the
• a result corresponding to the command is computed by the ultrasonic application server, and transmitted to the external application by the integrated interface program.
• circuit boards or circuit panels that are mounted within a generally rectangular cavity within a hand-held housing.
• the circuit panels each have one or more integrated circuits and are mounted in planes that are parallel to one another.
• These integrated circuits can be fabricated using a standard CMOS process that will support voltage levels between 3.3N and 200N.
• a particular embodiment of the invention utilizes two or three circuit boards or panels, a center panel having a center system controller and a communication link to an external processor.
• the center panel can be mounted between a pair of surrounding panels, each including a memory and a beamforming circuit.
• the system accommodates the use of different probe
• 25 elements can employ a variable power supply that is adjusted to different levels for different probes. Also, it is desirable to use a variable clock generator so that different frequencies can be selected for different probes.
• Another preferred embodiment of the invention provides a small probe that is connected by a first cable to an interface- housing.
• the 30 interface housing can contain the beamformer device and associated circuits and is a small light weight unit that can be held in one hand by the user while the other hand manipulates the probe.
• the probe can be any of several
• the interface housing can be worn on the body of the user with a strap, on the forearm or the waist with a belt, for example, or in a pocket of the user.
• a preferred embodiment using such an 5 interface can include two or three circuit boards as described in greater detail herein.
• the interface housing is connected to a personnel computer by standard Fire Wire or serial bus connection.
• the probe incorporating the beamformer, or the probe with the interface housing can be connected to a
• the computer performing scan conversion, post signal processing or color doppler processing is located in a housing worn by the user, such as on the forearm, on the waist or in a pocket.
• a power supply board can be inserted into the probe, into the interface housing or in another external pod and can include a DC-DC
• the display system can also include a head mounted display.
• a hand-held controller can be connected to the computer or interface by wire or wireless connection.
• a preferred embodiment of the invention can utilize certain safety features including circuits that a check the power supply voltage level, that
• These controls provide for freezing or unfreezing of the image on the display, for recording an image in electronic memory, to measure distances in two dimensions using a marker or caliper and a "set" function fix two markers or calipers on screen, a track ball, touchpad or other manually manipulated
• a time gain compensation control such as 8 slide pots, to correct for sound attenuation in the body, scale or depth control to provide a zoom feature and for selection of focal zones.
• the system can be employed with a number of probe system and imaging methods. These include the generation of color Doppler, power Doppler and spectral density studies. These studies can be aided by the use of contrast agents that are introduced into the body during a study to enhance 5 the response to ultrasound signals. Such agents can also include medications that are acoustically released into the body when they are activated by specific acoustic signals generated by the probe transduce array.
• a system for ultrasonic imaging including a probe and a computing device.
• the probe and a computing device.
• the 10 has a transducer array, and a control circuitry and a digital communication control circuit.
• the control circuitry includes a transmit/receive module, beamforming module and a system controller.
• a computing device connects to the digital communication control circuit of the probe with a communication interface. The computer processes display data.
• the communication interface between the probe and the computing device is a wireless interface in several embodiments.
• the wireless is a RF interface
• the wireless interface is an infrared interface.
• the communication interface between the probe and the computing device is a wired link.
• the beamforming module is a charge domain processor beamforming module.
• the control circuitry has a pre- amp/TGL module.
• a supplemental display device is connected to the computing device by a second communication interface.
• the supplemental display device is a
• At least one of the communication interfaces is a wireless interface.
• the communication between the probe and the computing device is a wireless interface.
• the second communication interface between the supplemental display device and the computing device is a wireless interface.
• the second communication interface includes a hub to connect a plurality of secondary supplemental devices.
• a method of controlling an ultrasonic imaging system from a unitary operating position facilitates ultrasonic image processing by defining ultrasonic imaging operations and defining a range of values corresponding to each of the ultrasonic imaging operations. An operator then selects, via a 5 first control, one of the ultrasonic imaging operations, and then selects, via a second control, a parameter in the range of values corresponding to the selected ultrasonic imaging operation. The ultrasonic imaging system applies the selected ultrasonic imaging operation employing the selected parameter. In this manner, the operator produces the desired ultrasonic image processing
• the ultrasonic imaging system is controlled from a control keypad
• the first control allows qualitative selection of the various ultrasonic imaging operations which may
• the second control allows quantitative selection of parameters along a range to be employed in the ultrasonic operation.
• the range of parameters may be a continuum, or may be a series of discrete values along the range.
• the control keypad includes two keys for scrolling through the qualitative ultrasonic operations, and two keys for
• the ultrasonic imaging operations which may be invoked include scanning operations, to be applied to live, real time ultrasonic image gathering, and processing operations, which may be applied to live or frozen ultrasonic images.
• Typical scanning ultrasonic imaging operations which are
• TGC TGC
• Typical processing ultrasonic imaging operations include view, inversion, palette, smoothing, persistence, map, and contrast.
• FIG. 1 is a schematic block diagram of an integrated probe system.
• FIGS. 2A-2C illustrate a particular embodiment of packaging integrated probe electronics.
• FIG. 3 A is a schematic block diagram of a particular embodiment of 15 an integrated probe system.
• FIGS. 3B and 3C illustrate embodiments of the transmit/receive circuit.
• FIG. 3D illustrates an alternate embodiment in which the probe housing is separated from the interface housing by a cable.
• FIG. 4A is a block diagram of a particular 1 -dimensional time- domain beamformer.
• FIG. 4B illustrates another preferred embodiment of a beamformer in accordance with the invention.
• FIG. 5 A is a functional block diagram of the system controller of 25 FIG. 3.
• FIG. 5B schematically illustrates a timing diagram for the control of modules in the system.
• FIG. 6 shows a block diagram of an ultrasonic imaging system adapted for external application integration as defined by the present claims.
• FIG. 7 A shows an integrated interface program operable for use with a local external application.
• FIG. 7B shows an integrated interface program operable for use with a remote external application.
• FIG. 8 shows a flowchart of external application integration as defined herein.
• FIG. 9 shows a graphical user interface (GUI) for use with the ultrasonic imaging system as defined herein.
• GUI graphical user interface
• FIG. 10 is a preferred embodiment of a portable ultrasound system in accordance with the invention.
• FIG. 11 illustrates a wearable or body mounted ultrasound system in 10 accordance with the invention.
• FIG. 12 illustrates an interface system using a standard communication link to a personal computer.
• FIG. 13 shows the top-level screen of a graphical user interface (GUI) for controlling the ultrasonic imaging system.
• GUI graphical user interface
• FIG. 14 shows a unitary control keypad for use in conjunction with the GUI of FIGS. 15A-15B.
• FIG. 15A shows a graphical user interface (GUI) for controlling the scanning operations of the ultrasonic imaging system.
• GUI graphical user interface
• FIG. 15B shows a graphical user interface (GUI) for controlling the 20 processing operations of the ultrasonic imaging system
• FIG. 16 shows a state diagram corresponding to the GUI of FIGS. 15A-15B.
• FIG. 17A is a block diagram illustrating an ultrasound imaging system with wired and wireless communication.
• FIG. 17B is a block diagram illustrating an ultrasound imaging system with wireless and wired communication.
• FIG. 17C is a block diagram illustrating an ultrasound imaging system with wireless communication.
• FIG. 18 is a block diagram illustrating an ultrasound imaging system 30 with a remote or secondary controller/viewer and wireless communication.
• FIG. 19 is a block diagram illustrating an ultrasound imaging system with wired and wireless network communication capability.
• FIG. 1 is a schematic block diagram of an integrated probe system. Illustrated are a target object 1, a front-end probe 3, and a host computer 5, and a supplemental display/recording device 9.
• the front-end probe 3 integrates a transducer array 10 and control circuitry into a single hand-held
• the control circuitry includes a transmit/receive module 12, a pre- amp/TGC module 14, a charge domain processor (CDP) beamforming module 16, and a system controller 18.
• Memory 15 stores program instructions and data.
• the CDP beamformer integrated circuit 16 includes a computational capacity that can be used to calculate the delay coefficients
• the probe 3 interfaces with the host computer 5 over a communications link 40, which can follow a standard high-speed communications protocol, such as the Fire Wire (IEEE PI 394 Standards Serial Interface) or fast (e.g., 200 Mbits/second or faster) Universal Serial Bus (USB 2.0) protocol.
• a standard high-speed communications protocol such as the Fire Wire (IEEE PI 394 Standards Serial Interface) or fast (e.g., 200 Mbits/second or faster) Universal Serial Bus (USB 2.0) protocol.
• Fire Wire IEEE PI 394 Standards Serial Interface
• fast e.g. 200 Mbits/second or faster
• USB 2.0 Universal Serial Bus
• the 20 computer operates at least at lOOMbits/second or higher, preferably at 200 Mbits/second, 400 Mbits/second or higher.
• the link 40 can be a wireless connection such as an infrared (IR) link.
• the probe 3 thus includes a communications chipset 20.
• the components in the portable ultrasound system require a
• the beamforaier 16 requires steering data
• the transmit circuitry 12 requires data to instruct it where to focus the next pulse and when to fire
• the TGC 14 needs to know what gain level is appropriate at the given time. Additionally, further information may be required synchronous to the scanning operation to
• a DAT A VALID signal can be helpful to reduce the amount of data that the
• FPGA Field Programmable Gate Array
• FIGS. 2A-2C illustrate a particular embodiment of integrated probe electronics.
• FIG. 2A is a perspective view showing a transducer array
• FIG. 2B is a back-end view of the probe, which also shows an upper Molex connector 150A.
• FIG. 2C is a side- view of the probe.
• Small size is achieved through the use of modem fabrication and packaging techniques. For example, by exploiting modem semiconductor fabrication techniques, numerous circuit functions can be integrated onto 15 single chips. Furthermore, the chips can be mounted using space-saving packaging, such as chip on-board technology. As technology improves, it is expected that the size of the electronic components will decrease further.
• More functionality can be included within the hand-held probe such as a wireless IEEE 1394 connection to the personal computer.
• a display can 20 be mounted directly on the hand-held probe, for example, to provide a more usable and user- friendly instrument.
• FIG. 3 A is a schematic block diagram of a particular embodiment of an integrated probe system.
• the host computer 5 can be a commercially available personal computer having a microprocessor CPU 52 and a 25 communications chipset 54.
• a communications cable 40 is comiected through a communications port 56 to the communications chipset 54.
• the front-end probe 3' includes a transducer head 32, which can be an off-the- shelf commercial product, and an ergonomic hand-held housing 30.
• the transducer head 32 houses the transducer arcay 10.
• the housing 30 30 provides a thermally and electrically insulated molded plastic handle that houses the beamforming and control circuitry.
• the beamforming circuitry can be embodied in a pair of analog circuit boards 100A, 100B.
• Each analog circuit board 100A, 100B includes a respective transmit/receive chip 112 A, 112B; a preamp/TGC chip 114A, 114B; a beamformer chip 116A, 116B; all of which are interconnected 5 with a pair of the memory chips 115A-1, 115B-1, 115A-2, 115B-2 via an operational bus 159A, 159B.
• the memory chips are Video Random Access Memory (VRAM) chips and the operational bus is 32 bits wide.
• preamp/TGC chips 114 and beamformer chips 116 operate on 32 channels simultaneously.
• VRAM Video Random Access Memory
• transmit/receive chips 112 include a 64 channel driver and a 64-to-32 demultiplexer.
• FIG. 4 A is a block diagram of a particular 1 -dimensional time- domain beamfomier.
• the beamformer 600 features 32-channel programmable apodized delay lines.
• the beamformer 600 can
• 15 include an on-chip output bandpass filtering and analog-to-digital conversion.
• the beamformer 600 includes a plurality of single channel beamforming processors 620 subscript I,..., 620 subscript J. imaging signals are represented by solid leader lines, digital data is
• a timing controller 610 and memory 615 interface with the single channel beamfomiing processors 620.
• Each single channel beamforming processor includes clock circuitry 623, memory and control circuitry 625, a programmable delay unit with
• Each programmable delay unit 621 receives an imaging signal echo E from a respective transducer element.
• the outputs from the single channel beamfonriing processors 620 are added in a summer 630.
• An FIR filter 640 processes the resulting imaging signal, which is digitized by the analog-to-
• both the FIR filter 640 and the A/D converter 650 are fabricated on chip with the beamforniing processors 620.
• VRAM is a standard Dynamic RAM (DRAM) with an additional higher-speed serial access port. While 5 DRAM has two basic operations e.g. read and write memory location,
• VRAM adds a third operation: transfer block to serial readout register. This transfers a block (typically 128 or 256 words) of data to the serial readout register which can then be clocked out at a constant rate without further tying up the DRAM core. Thus refresh, random access data read/write, and
• dual-ported operation is beneficial so the data loading performed by the host 5 can be decoupled from data sent to memory modules.
• a modular architecture which allows additional VRAMs to be added in order to obtain additional bandwidth is useful, particularly when the
• a particular embodiment uses five 256Kword by 16 bit VRAMs which yields a total of 80 output lines. If fewer output lines are required, fewer VRAMs can be used. If more output lines are required, only
• VRAM is lower density than other varieties of DRAM.
• SDRAM Synchronous DRAM
• the control circuitry is embodied in a digital circuit board 200.
• the digital circuit board 200 includes a Fire Wire chipset 220, a system control chip 218 to control the scan head, and a memory chip 215.
• the memory chip 215 is a 5 VRAM chip and the system control chip 218 is interconnected to the various memory chips 115, 215 over a control bus 155, which in this particular application is 16 bits wide.
• system control chip 218 provides scan head control signals to be transmit/receive chips 112 A, 112B over respective signal lines
• the transmit/receive chips 112A, 112B energize the transducer array 10 over transmit lines 124 A, 124B. Received energy from the transducer array 10 is provided to the transmit/receive chips 112 A, 112B over receive lines 122 A, 122B. The received signals are provided to the preamp/TGC chips 114A, 114B. After being amplified, the signals are provided
• Control signals are exchanged between the beamformer and the system controller over signal lines 154A, 154B to adjust the scan beam.
• the five VRAM chips 115A-1, 115A-2, 115B-1, 115B-2, 215 serve to supply the real-time control data needed by the various operating modules.
• operating modules refers to the different parts of the system that require control data - namely the beamfomiers 116A, 116B, transmit/receive chips 112A, 112B, and preamp/TGC chips 114A, 114B.
• the system controller 218 maintains proper clocking and operation of the VRAM to assure continuous data output. Additionally, it generates clocks and control
• VRAM 25 signals for the various operating modules of the system so that they know when the data present at the DRAM serial port output is for them.
• PC PC communications protocol
• Some of the VRAMs are shared by multiple modules.
• the 64-bit * 30 output of four VRAMs 115A-1, 115A-2, 115B-1, 115B-2 is used byboth the transmit module as well as the beamformer. This is not a problem, because typically only one requires data at any given time. Additionally, the transmit
• DOC:! module chip uses relatively less data and thus it is wasteful to have to dedicate entire VRAMs for transmit operations.
• codes are embedded in the VRAM data that the controller deciphers and asserts the appropriate MODCLOCK line.
• the fifth VRAM 215 is used to generate data that is not shared by multiple modules. For example, it is convenient to put the control for the TGC here because that data is required concurrently with beamformer data. It can also be useful to have one dedicated control bit which indicates when valid data is available from the beamformer and another bit indicating frame boundaries. Thus, because the location of the data in the VRAM corresponds to the position in the frame scanning sequence, additional bits are synchronized with the operation of the system. CCD clock enable signals can also be generated to gate the CCD clock to conserve power. Lastly, the VRAM can be used to generate test data for a D/A converter to test the analog circuitry with known waveforms.
• the number of VRAMs maybe reduced.
• the four shared VRAM chips may be merged into two SDRAM chips in a 128 line system, for example.
• the data sent to the beamformer and transmit modules are bit-serial within a channel, with all channels being available in parallel.
• For the transmit module two transmit channels share each bit line with alternating clocks strobing in data for the two channels. All per channel transmit module coefficients (such as start time) are presented bit-serially.
• a mn consists of a one word header, which is interpreted by the VRAM controller, followed by zero or more actual data words which are used by the various modules.
• the headers (see Table 1) specify where the data in the n is destined, how fast it should be clocked out, and how many values there are in the mn. (Note that the mn destination is only for the data coming out of the 4 VRAMs. The bits coming out of the controller VRAM always have the same destinations.)
• the headers are also used to encode the special instmctions for Jump, Pause, and
• the data in the VRAM are read out basically sequentially but some variations are allowed to reduce the memory requirements and facilitate system operation based on several observations about how the ultrasound system operates.
• the RATE field allows the specified n to be clocked out at either the full system clock rate (which can be 8-32 MHZ), one-half, one-quarter, or one-eighth of that rate.
• RATE field can only take on the values 0, 2 and 3 because a pause of RATE 1 is interpreted as a wait command, described next. This is not a problem, however, because typically only RATE 0 is used for maximum wait accuracy (to within one clock) and RATE 3 is used for maximum wait time (up to 16376 clock cycles).
• the buffering is achieved by a 16K by 18 FIFO while the flow control is achieved by feeding the FIFO fullness indication back to the system controller 218. In this way, if the FIFO becomes too full, the scanning stops until the FIFO has been emptied. However, the scanning should not stop arbitrarily because it is timed with the propagation of the sound waves. Thus explicit synchronization points can be inserted into the code, and at these points the controller waits until the FIFO is empty enough to proceed safely. The wait command is used to indicate these synchronization points.
• the wait command causes the controller to wait until the WAITPROCEED line is high. Currently this is connected (via the aux FPGA) to the "not half-full" indicator on the FIFO. Thus the wait commands can be placed at least every 8K. data-generating cycles to assure that data overflow cannot occur. Because this is greater than one ultrasound line, it still allows multi-line interleaving to be used. -18-
• the next command is the jump command.
• This allows nonsequential traversal through the VRAM memory. This is employed so that the VRAM memory can be modified concurrently with the readout operation and also to make it easier to add and remove variable size control sequences. 5 To understand why this is useful, consider the following example: Imagine that one wants to change the data in VRAM locations 512-1023 while continuing operation of the scanning using the other locations. If the host were to just modify locations 512-1023, there is no guarantee that they will not be used exactly when they are in the middle of being modified. Thus the
• the last command is the end command. This is used at the end of the sequence for a frame to tell the system controller that the frame has completed. The controller then stops fetching instructions until it is restarted (from location 0) by host if it is in single- frame mode. If it is in continuous mode then it will start immediately on the next frame. (After 128 cycles
• FIG. 5 A is a functional block diagram of the architecture of the system controller of FIG 3 A.
• the system controller 218 has four basic parts:
• the first three support the three basic operations on the VRAM: reading out data, writing in of data at host's request, and refreshing the DRAM core.
• the arbiter 288 is responsible for merging the requests of 5 the first three sections into one connection to the VRAM's DRAM core. Only one of the first three sections can have control at a given time, so the explicitly request control and wait until this request is acknowledged by the arbiter 288. They also must tell the arbiter 288 when they are still using the DRAM so that the arbiter knows not to grant it to one of the other sections.
• the arbiter 288 sends the host controller 284 a RELREQ or relinquish request signal to ask the host controller 284 to give up ownership of the DRAM core because some other section wants it. Note that only the host 284 controller needs to be asked to relinquish the bus because
• the host controller 284 can hold on to the DRAM as long as there is data coming over the Fire Wire to be written into the DRAM, so it needs to be told when to temporarily stop transferring data.
• VRAM serial section of the VRAMs is not multiplexed -it is always controlled by the readout controller 282.
• the VRAM serial data also only goes to the readout controller 282.
• the readout controller 282 controls the sequencing of the data out the VRAMs' serial access ports. This involves parsing the data headers to
• the host controller 284 is the part of the VRAM Controller that
• the 30 interfaces to the host 5 via Fire Wire to allow the host to write into the VRAM.
• the host wants to write into the VRAM, it sends asynchronous packets specifying which VRAM and which addresses to
• the host controller 284 then asks the arbiter 288 for access to the VRAM.
• the arbiter 288 grants control to the host controller 284.
• the host controller 284 then takes care of address and control signal generation.
• the host controller 284 releases its request line giving up the DRAM control, allowing the other two sections to use it.
• the refresh controller 286 is responsible for periodically generating refresh cycles to keep the DRAM core of the VRAM from losing its data.
• the refresh controller 286 has its own counter to keep track of when it needs to request a refresh. Once it gains access to the VRAMs via the arbiter 288, it generates one refresh cycle for each of the VRAMs sequentially. This reduces the amount of spikes on the DRAM power supply lines as compared to refreshing all 5 VRAMs in parallel.
• REFRATE inputs control how many system clock cycles occur between refresh cycles. (See Table 3.) This is compensate for different system clock rates. Additionally, refresh may be disabled for debugging purposes.
• the arbiter controls 288 the access to the VRAM by the Readout
• Host, and Refresh Controller 282, 284, 286 sections Only one section may have access to the DRAM port of the VRAM at any given time.
• the arbiter 288 does not reassign control of the VRAM to another section until the section with control relinquishes it by de-asserting its IN JSE line.
• the readout controller 282 needs access to the VRAM, but does not get it, then the system may break down as the serial output data will be incorrect.
• the refresh controller 286 can tolerate occasional delay, although it should not happen much.
• the host controller 284 can potentially 5 tolerate very long delays because the host can be kept waiting without too many consequences except that the writing of the VRAM may take longer.
• Fire Wire standard also known as IEEE 1394.
• the Fire Wire standard is a highly capable, yet cost-effective and physically non-encumbering connection between the scan head and host computer.
• Fire Wire protocol 10 used for multimedia equipment and allows 100-200Mbps and preferably in the range of 400-800Mbps operation over an inexpensive 6 wire cable. Power is also provided on two of the six wires so that the Fire Wire cable is the only necessary electrical connection to the probe head.
• a power source such as a battery or IEEE1394 hub can be used.
• CardBus-to-FireWire boards can also be used.
• VRAM controller directly controls the ultrasound scan head, higher level control, initialization, and data processing and display comes from a general purpose host such as a desktop PC, laptop, or palmtop
• the display can include a touchscreen capability.
• the host writes the VRAM data via the VRAM Controller. This is performed both at initialization as well as whenever any parameters change (such as number or positions of zones, or types of scan head) requiring a different scanning pattern. During routine operation when data is just being continually read
• the host need not write to the VRAM. Because the VRAM controller also tracks where in the scan pattern it is, it can perform the packetization to mark frame boundaries
• Fire Wire chipsets manage electrical and low-level protocol 5 interface to the Fire Wire interface
• the system controller has to manage the interface to the Fire Wire chipset as well as handling higher level Fire Wire protocol issues such as decoding asynchronous packets and keeping frames from spanning isochronous packet boundaries.
• Asynchronous data transfer occurs at anytime and is asynchronous
• Asynchronous data transfers take the form of a write or read request from one node to another.
• the writes and reads are to a specific range of locations in the target node's address space.
• the address space can be 48 bits.
• the individual asynchronous packet lengths are limited to 1024 bytes for 200Mbps operation. Both reads and writes are supported
• AsynchiOnous writes are used to allow the host to modify the VRAM data as well as a control word in the controller which can alter the operation mode.
• Asynchronous reads are used to query a configuration ROM (in the system controller FPGA) and can also be used to query external registers or I/O such as a "pause" button.
• ROMs contain a querible "unique ID" which can be used to differentiate the probe heads as well as allow node-lockings of certain software features based on a key.
• a node reserves a specified amount of bandwidth, and it gets guaranteed low-overhead bursts of link access every
• the asynchronous write request packets are sent from the host to the
• the Adaptec API and device driver take care of assembling the packets.
• the destinationID field holds the node ED of the destination which is the probe head Fire Wire controller.
• the physical layer chip can use this to determine if the packet is for it.
• the system controller can ignore this field.
• the tLabel field is used to match requests and responses. For write requests, this does not matter and can be ignored.
• the rt is the retry code used at link and/or phy level. It is not used by the system controller.
• the tCode field is the transaction code which determines what type of packet it is. In particular 0 is for quadlet write requests and 1 is for block write requests. The system controller parses this field to determine what type of packet it is. Currently only tCode values of 0 and 1 are recognized.
• the priority field is used by the PHY chip only and is ignored by the system controller. It is used in, i.e. in selecting which unit on the interface is to receive a particular packet
• the destinationOffsetHi and destinationOffsetLo fields form the 48 but destination start address. This indicates within the node what the data should be used for.
• the system controller used the destinationOffsetHi to determine the function as shown in Table 6. Note that only the 3 least
• the spd field indicates the speed at which the data was sent while the ackSent field is use to indicate status by saying how the LINK chip acknowledged the packet.
• destinationOffsetHi values of 0-4 correspond to writing the VRAMs.
• the destinationOffsetLow is set to the byte address to start writing. This is twice the standard VRAM address which is typically formed in 1 -bit words. Note also that the start address (destinationOffsetLow) and the length (dataLength) can both be multiples of
• the payload data is little endian and thus need not be converted if written by an Intel PC host.
• the length (dataLength) must additionally be between 4 and 128 bytes due to the size of the GPLynx FIFO.
• the total FIFO size is 200 bytes, but 72 bytes are 5 dedicated to the asynchronous transmit FIFO required for read responses.
• a destinationOffsetHi value of 5 signifies that the system controller ISO Packet Length register is to be written.
• the ISO Packet Length has to be set in the controller to allow it to correctly format the ISO packets back to the host via Fire Wire. An explicit counter in the system controller is used due to
• the TI GPLynx chip does not assert the end-of-packet indication until one word too late.
• the ISO Packet length also has to be set in the LINK chip.
• the value written is the number of 16-bit words in the ISO Packet length which also has to be set in the LINK chip.
• the value written is the number of 16-bit words in the ISO packet (i.e. bytes/2) and it is written in
• Specifying a destinationOffsetHi value of 6 signifies that the system controller mode word is to be modified. Currently only the least significant 16 bits are used out of each quadlet and all quadlets go to the same place so
• the BOF Word field is used to set the value that the system controller will put in the high byte of the first word of an isochronous packet to indicate the beginning of frame.
• the BOF word field can be set to some value that is ⁇ rr TCMTCx. um ⁇ O ⁇ nn ⁇ U nn ⁇ nnr.i i not likely to occur in typical data. This not cmcial, however, because choosing a BOF word that occurs in the data will make it more likely to miss incorrect frame synchronization but will never cause false alarms where it thinks it is mis-synchronized but is really correctly synchronized.
• the initial value upon reset is 80 hex.
• the AbortFrame, SingleFrame, and Run bits are used to control the system operation. Their use is shown in Table 8.
• the data FIFO is never allowed to fully empty so an entire frame can not be read out until part of the next one is the queue.
• the DataLoopback bit is used to control whether the data that is read back from the host comes from A/D or from one of the VRAMs. (Currently this is VRAM 1.) This second option can used for test purposes to test the VRAMs.
• a 0 in the DataLoopback bit indicates normal operation of reading from A D while a 1 means that it should get data from the VRAM.
• the Extra 1 and Extra2 bits are available for general use. They are latched by the system controller and currently brought out on pins called
• EXTRACLOCKO and EXTRACLOCKl can be used for any purpose.
• destinationOffsetLow specifies the first register to write. Because the registers are all 4-bytes in size and must be written in their entirety, destinationOffsetLow and dataLength must both be multiples of 4. Multiple consecutive registers can be written with a single packet. Note that the data
• Read request packets are used to asynchronously read data from the probehead. This currently only consists of configuration ROM data (see below) but can be easily used for other types of data such as status information or button indications.
• the Adaptec device drivers send Asynchronous Read Requests in response to explicit application requests as well as to interrogate the node's Fire Wire configuration ROM in response to a SendPAPICommand of
• Asynchronous read requests can either be of the quadlet or block variety as with the asynchronous write requests.
• the formats are shown in
• Table 9 and Table 10 are similar to the write request fomiats.
• the destinationOffsetHi and destinationOffsetLow determine what is being requested.
• the high addresses are defined for use as Control and Status Registers and the configuration
• the spd, tLabel, rt, an priority values are copied from the request packet.
• the destin ⁇ tionID is taken from the sourcelD of the request packet. Note that all packet CRCs are generated by the TI LINK chip and are thus note included the data that the system controller must generate. (The ROM 15 CRCs do have to be computed explicitly off-line.)
• the rCode field is used to indicate the status of the reply. In particular, 0 means resp_complete indicating all is well. A value of 6 means resp_type_error indicating that some field of the packet was invalid or unsupported. In this case, if the request was a block request then the
• the Fire Wire specification expects each Fire Wire node to have a configuration ROM that contains various details about the device, its requirements, and its capabilities. This ROM is to be queried via Read Request packets. There are two types of ROM implementations: a minimal
• the former has only one quadlet (4-byte) piece of data indicating a 24-bit vendor DD.
• the general ROM has many other fields, and many which are optional ranging from the ASCII name of the vendor and device to its power consumption and how to access its capabilities.
• One of the required fields in a general ROM is a node unique ID.
• the application reads its configuration ROM and determines if it
• the 25 wants to work with it. If so it records its node unique ID and opens a connection to the device via that node unique ID. This is then at any given time mapped to its Fire Wire ID (16-bit) by the host adapter and its device driver. If the topology changes or a Fire Wire bus reset occurs, the node's Fire Wire ID can change, however the node unique ID will not. Thus, in such
• the adapter automatically determines the new Fire Wire ID and continues. Thus for smooth operation, particularly with multiple heads
• the configuration ROM is divided into several sections.
• the sections of particular interest are the first word, which defines the length and CRC of the ROM, the next 4 words comprising the Bus_Info_Block, which gives some fixed 1394-specific information (such as Node Unique ID), and the last 3 words representing the Root Directory which is a set of key- value tagged entries. Only the two required key-value pairs are included the ROM built into the FPGA.
• An 8-word ROM that can be used is shown in Table 13.
• Isochronous packets are used for the probehead-to-host communication of beamformed data. This is conceptually a stream of 16-bit numbers punctuated by frame markers. The frame markers are important to keep in sync with where in the frame the data corresponds. While some
• the integrated system can use a single auxiliary bit, which is not sent as part of the data, to mark frame boundaries.
• Line boundaries can be derived by knowing the VRAM sequencing program.
• isochronous packets can be used as low-overhead way to send a guaranteed rate of data. Once a peripheral reserves a specified amount of bandwidth, it gets guaranteed bursts of link access every 1/8000 second. All data from the head to the host is sent via isochronous packets. Because isochronous packets are limited to
• the Fire Wire specification describes the use of synchronization bits which can be used to tag each isochronous packet with a 4 bit SYNC code.
• the Adaptec FireWire-to-PCI bridge can then use the Sync field to assure proper frame alignment.
• the TI GPLynx Controller chip only supports frame-level granularity of when to send packets and not packet level so when the System Controller tells the Fire Wire link chip it has data, it must be prepared to send a whole frame of data. Because the FIFO is much smaller than a frame, a sage option is to reduce the effective Fire Wire frame size to one packet.
• the first step is to reserve isochronous bandwidth.
• This reservation causes a central record of the request (in the Fire Wire isochronous cycle manager node) to be kept to assure that the total bandwidth allocated does not exceed the total bandwidth of the link.
• this reservation is achieved using the Adaptec API BusConfig 0 command with Cmd field set to P_ALLOCATE_RESOURCE.
• a requested payload in bytes is passed in. This can be the amount of data desired in every 1/8000 second. Setting this value too high simply wastes reserved bandwidth on the Fire Wire interface which is not a problem if there is only one device. Setting this value too low may constrain the head-to-host data rate. No overflows or data loss are likely to occur, the scanning may simply proceed slower.
• the resource allocation call will return both an isochronous channel number as well as the payload size granted. This payload size granted may be less than that requested if part of the link has already been reserved.
• the next step is to set the system controller ISO packet length word to tell how long of an ISO packet to expect.
• the final step is to initialize the probehead LINK chip. This is done via the writeback to LINK chip asynclironous packets described above. In 5 particular, initializing registers 54h, 58h, and 5ch is necessary. The probehead can then be told to start sequencing and the data will flow back. If multiple probes are connected to the system then the isochronous bandwidth reservation can take place once but at any given time, only one probe's isochronous transmission (as well as its sequencing) is enabled. 10 As previously described, isochronous data transfers are used to deliver the probe head data to the host. Maintaining frame synchronization is necessary. The Fire Wire will support sub-frame packetization of about 3000 bytes but it is up to the system controller to implement frame synchronization on top of this. Synchronization is achieved via two methods: 15 1. The high byte of the first word in the first packet of a frame is set to the Beginning of Frame (BOF) code. (This can be set in the system controller Mode word).
• BOF Beginning of Frame
• All frames are padded to consume a whole number of packets. When these two are combined, they guarantee that frame 20 synchronization will be maintained if the correct number of packets are read at a time and the ⁇ synchronization can be effected by just scanning the high- byte of the first word of each packet in the data stream.
• An example packetization is shown in Table 14. This depicts 4 packets of 4 words (8 bytes) apiece showing one complete ultrasound frame 25 and the first packet of the next frame.
• the ultrasound frame size is 10 words.
• the Hi byte of the first word is set to the BOF code. This can be examined to assure that proper synchronization has been maintained.
• the data is then split into the three packets 1-3. Because the frame ends in the middle of packet 3, the end of packet 3 is padded with the BOF code in the 30 high word. Importantly, this means that the first word of the fourth packet will be the first word of the second frame even though the ultrasound frame size is not a multiple of the packet size.
• the TSB12LV31 (or 32) performs packetization of the isochronous data but informs the system controller of packet boundaries via the ISORST signal. The system controller then uses this to reset its internal word-to-byte multiplexer as well as packetization circuitry. If it receives a frame marker
• the module interface defines how the various modules in the system are controlled by the VRAM controller. There are two types of modules, those that receive data from the four VRAMs which are shared (two on each
• FIG. 5B shows typical timing for the different module interfacing modes for a typical program sequence.
• VRAMDATA the data from the loopback 5 VRAM, control the execution.
• the diagonal shaded boxes denote header data used by the VRAM controller while the shaded boxes denote module data in FIG. 5B.
• the data in the four other VRAMs go to the modules.
• the data from the first VRAM is looped back into the system controller and then used for dedicated data supply for things like the TGC, feedback control, etc. 10 h clocks 1-4 in FIG. 5B a mn of data at a rate 1/1 destined for module 0.
• the header is clocked out at clock 1.
• the pulse of NEWRUNCLOCK at clock 1 lets the modules know that the next clock will be the first in a ran. They thus reset their internal run-related state if necessary.
• the data is clocked out during clocks 2, 3, and 4. Since the data 15 is destined for module 0, the MODCLOCKO is pulsed once per new data word. Module 0 should latch the data at VRAMDATA on the rising edge of MODCLOCKO.
• FIG. 5B must be observed carefully. Since the access time of the VRAM is
• the modules accepting data at the full rate must additionally make
• MODULEFASTCLOCK0 signal follows the MODULECLOCK0 line. They will only differ when 1/2,1/4, or 1/8 rate data is used.
• MODCLOCK2 is only clocked once per new data word
• MODULEFASTCLOCK2 is clocked once per master clock for the duration
• the MODNEWDATA signal can also be used by modules using the MODFASTCLOCK lines to determine on which of the fast clocks new data has been presented.
• NEWRUNCLOCK is sequenced as usual but no MODCLOCK or MODFASTCLOCK is generated.
• FIG. 4B Such a configuration is shown in FIG. 4B, for 5 example, in which the 64 or 128 chaimel (660 ⁇ - 660j) system is configured on one or two printed circuit boards, hi this two board system, the T/R circuit and the preamplifier/TGC circuit are fabricated in a single integrated circuit and are placed on one board with a CDP beamfomier that is formed as a second integrated circuit.
• the beamfomier control circuits can include the
• the memory for this system is either a SDRAM or VRAM located on the second board along with the system controller and the digital communication control circuit.
• the standard Fire Wire cable 40 includes a plurality of Fire Wire signal lines 42 and a Fire Wire power line 44.
• the Fire Wire power line 44 is fed to an inline DC-DC converter 300.
• the DC-DC converter 300 generates the necessary voltages and provides them over a plurality of power lines 46. These new power lines 46 are repackaged with the Fire Wire signal lines 42 in a custom cable 40'. In the probe housing 3', the Fire Wire signal lines 42
• the Fire Wire chipset 220 are connected to the Fire Wire chipset 220 and the custom power lines 46 are connected to a power distributor 48, which filters and distributes the various voltages over respective internal voltage lines 148 A, 148B, 248.
• the power distributor 48 may perform additional DC-DC conversions, as described in more detail below.
• the transmit/receive control chip is needed to interface with the transducer array.
• the chip can provide delays to the high- voltage driving pulses applied to each of the selected transducer elements such that the transmitted pulses will be coherently summed on the image place at the required transmit focus point.
• a receive mode it provides
• the core function of the transmit/receive chip includes a global counter which broadcasts a master clock and bit values to 5 each channel processor; a global memory which controls transmit frequency, pulse number, pulse sequence and transmit/receive select; a local comparator which provides delay selection for each channel. For example, for a 60 MHZ clock and a 10 bit global counter, it can provide each channel with up to 17 ⁇ s delay; a local frequency counter which provides programmable transmit
• a local pulse counter which provides different pulse sequences.
• a 7-bit counter can provide programmable transmitted pulse lengths from one pulse up to 128 pulses; a locally programmable phase selector which provides sub-clock delay resolution. For example, for a 60MHz master clock and a two-to-one phase selector provides 8 ns delay
• a phase of the clock that is programmable on a per-channel basis, hi the simplest form, a two-phase clock is used and the output of the frequency counter- is either gated with the asserted or Deasserted clock. Alternatively, multiple skewed clocks can be used. One per channel can be selected and used to gate the coarse timing signal from the frequency counter.
• a semiconductor process that can support both high- voltage and low- voltage operations is ideally matched for a single- chip solution to the transmit/receive chip described above.
• the core function of the transmit/receive chip can be implemented on low- voltage transistors to reduce power consumption.
• the level-shifting function can be implemented
• a multi-chip module 295 can be used to implement a transmit/receive chip.
• a deep-sub- micron process can be used to implement the core function 296 of the module, and a separate process can be used to implement the buffer 298 function.
• the multi-chip set can be mounted in a
• FIG. 3D illustrates an alternate embodiment in which the transducer array 10' is located in a separate probe housing 410 connected to the interface
• FIG. 15 housing 404 by a cable 412.
• a probe housing in which certain circuit elements such as the transmit/receive circuitry and/or the preamp/TGC circuitry is included with the transducer array while the beamformer, system control and memory circuits remain in the interface.
• the system in FIG. 3D provides for the use of standard probes and a beamfomier interface that weighs less than 10 lbs and which can be connected to a standard personal computer.
• the interface 404 has a volume of less than 1500 cm 3 and a weight that is preferably less than 5 lbs.
• FIG. 6 shows a block diagram of another particular embodiment of an
• the transducer array housing 32 and associated circuitry are connected to a system controller 500 via an ultrasound (US) interface 502.
• the system controller 500 is connected to a host user computing device 5 such as a PC via a standard interface 40 which is a predetemiined
• the US data therefore, is transmitted to a user computing device 5 via the standard interface 40, relieving the need for specialized components
• the user computing device 5 therefore provides an ultrasonic application server which may be integrated with an external application, as will be described further below.
• the ultrasonic application server miming on the user computer device 5 5 therefore, receives the US data, and makes it available to be invoked by an external application for further processing.
• the external application may be either local, and therefore miming on the user computer device 5, or remote, and accessing the ultrasonic application server remotely.
• FIG. 7A shows an integrated interface program operable for use with
• the ultrasonic server application 504 is running on the user computing device 5.
• a local external application 506 is also running on the user computing device 5, and transmits to and from the ultrasonic server application 504 via an integrated interface program 508.
• the integrated interface program 508 contains a series of
• the local external application 506 sends a command, which includes an instruction and optional parameters as defined by the predetermined entry points 510.
• the 20 transmits the command to the ultrasonic server application 504 by invoking the entry point 51 On in the integrated interface program which corresponds to intended operation.
• the entry point may be invoked by procedure or function call via a stack call, message transmission, object passing, or other suitable interprocess communication mechanism.
• Windows® messages may be used.
• the command is received by the ultrasonic server application 504 via the desired entry point 51 On from the integrated interface program 508, and is processed.
• the ultrasonic server application 504 executes a result corresponding to the desired function, and transmits the result back to the
• the operations performed by the ultrasonic application server may include the following:
• the local external application 506 may be
• the 15 may access the integrated interface program 508 by computing the proper instructions and parameters of the commands as defined by the integrated interface program 508.
• the external application is operable to process 2 dimensional and 3 dimensional radiation therapy data, fetal image
• radiation therapy data may be employed to simultaneously display information about the direction and intensity of radiation treatment, and a visual image of the treatment area.
• Such visual image data may also be employed in image guided surgery, to 5 indicate the location of a surgical instmment. Such information is particularly useful in contexts such as brain surgery, where it may not be possible to expose the afflicted area.
• FIG. 7B shows an integrated interface program 508 operable for use with a remote external application.
• a remote external application operable for use with a remote external application.
• a remote remote application operable for use with a remote external application.
• a remote remote application operable for use with a remote external application.
• the integrated interface program 508 includes connection points 516a..516n such as remote procedure call (RPC) points or other inter-node communication
• RPC remote procedure call
• connection points are sockets in accordance with the TCP/IP protocol.
• the remote external application 512 is operable to compute a command corresponding to an intended operation in the ultrasonic application server 504.
• 20 points 516n are generally operable to receive a command transmitted from the remote external application 512.
• the ultrasonic application server 504 sends a result corresponding to the command, and transmits the result back to the remote external application 512 via the integrated interface program 508 by an inter-node communication mechanism such as that used to transmit the
• the same integrated interface program could have both entry points 51 On, generally to be accessed by the local external application 506, and connection points 516n, generally accessible by the remote external application 512.
• FIG. 8 shows a flowchart of external application integration.
• an external application determines a desired US operation to be employed in processing and/or analysis, as depicted at step 550.
• the operation may provide data, and may cause a
• the external application determines the instmction corresponding to this operation, as shown at step 552, as defined by the integrated interface program. The external application then determines if any parameters are required for the operation, as disclosed 5 at step 554. If parameters are required, the external application determines the parameters, as depicted at step 556. If no parameters are required, execution continues.
• the external application detemiines a command including the instmction and any required parameters, corresponding to the desired US operation, as shown at step 558. The command is transmitted to
• the transmission may be by any suitable method, such as those described above and others, depending on whether the external application is local or remote.
• Ultrasonic data is received by the ultrasonic server application 504
• the ultrasonic data is received via a test probe disposed in contact with the subject, or patient, for viewing such visual infomiation as radiation therapy data, fetal image data, cardiac image data, and image guided surgery data.
• Information such as
• step 564 may involve control signals being generated to define or re-define a region of interest in which radiation is to be directed for treatment.
• the ultrasonic application server 504 then transmits the computed result to the external
• 30 includes both entry points for local external applications, and connection points for remote external applications.
• the instructions and parameters coreesponding to the entry points are known to the local external application,
• connection points are known to the remote external application.
• Both the local and remote external applications invoke the ultrasound application server via the integrated interface program 508 (FIGS. 7A and 7B).
• the ultrasonic application server also includes a graphical user
• a control bar 578 of a top level GUI screen is shown.
• the control bar allows manipulation of tools affecting image settings of the display via image control presets.
• the image settings are controlled for each of three sizes small 570a, medium 570b, and large 570c.
• the image settings within that size may be controlled, including depth 572, focus 574, and time gain compensation 576. Each of these settings may be saved under a user defined name for later recall. The user clicks on a save button and is prompted to enter a file name.
• 20 570c is then stored corresponding to the file name, and may be recalled by the user at a later time.
• broadband signaling techniques as in an electronic network such as the Internet or telephone modem lines.
• the operations and methods may be implemented in a software executable by a processor or as a set of
• the operations and methods may be embodied in whole or in part using hardware components, such as Application Specific Integrated Circuits (ASICs), state machines, controllers or other hardware components or devices, or a combination of 5 hardware, software, and firmware components.
• ASICs Application Specific Integrated Circuits
• FIG. 10 illustrates a preferred embodiment of a portable ultrasound system 470 in accordance with the invention.
• a personnel computer 472 such as a laptop, a hand-held computer or a desktop workstation can provide power and a standard interface (e.g. IEEE 1394 or USB) to a housing 474
• a standard interface e.g. IEEE 1394 or USB
• Housing 474 includes a DC-DC converter to deliver power along cable 480 to interface housing (482,490).
• This interface housing has two or three circuit boards 484,486, 488 as described previously.
• a standard transducer housing 496 with transducer an * ay 498 is connected to the interface housing along cable 494 and connector 492.
• FIG. 11 illustrates a wearable ultrasound imaging system that can include a belt mounted computer 360 or interface connected big cable 362 to
• a second hand-held unit 368 that can include various controls including a mouse control and buttons to freeze the image displayed or to store a particular image in electronic memory.
• the unit 368 can be comiected by wireless (RF or infrared) connection or by cable 366 to housing 360.
• the computer 360 can be connected to a desktop, laptop or hand-held
• a headmounted display system 370 that includes a microphone, a pair of speakers for audio and a high resolution display positioned adjacent the user's eye.
• FIG. 12 Another preferced embodiment is illustrated in FIG. 12 in which a laptop computer 450, having a flat panel display and a standard keyboard,
• the computer 450 and/or the interface can optionally include a control panel 452, 456, that can be used to control the study being conducted.
• a preferred embodiment of the interface housing 5 454 is controlled solely by the personnel computer 450 and provides for the use of standard transducer array probes that can be interchangeably attached to the interface housing 454 with a cable.
• an additional remote controller 464 can be used to control system operation.
• the interface 454 can house the circuit boards on which the beamformer, memory, system
• the interface 454 is comiected to the hand-held probe 460 with a cable that is preferably between two feet and six feet in length, however longer lengths can be used.
• the transmit/receive and/or the preamplifier/TGC circuits can be in the probe housing 460 or in the interface housing 454.
• the computer can also be
• the video data can also be sent to a VCR or standard video recorder or video camera with an IEEE 1394 part for recording on videotape.
• the VCR or video camera can be controlled using the computer.
• the host 5 can be a desktop, laptop palmtop or other portable computer executing software instmctions to display ultrasound images.
• Doppler ultrasound data can be used to display an estimate of blood velocity in the body in real time.
• CFI color-flow imaging
• Doppler power- Doppler
• spectral sonogram 25 different velocity estimation systems exist: color-flow imaging (CFI), power- Doppler and spectral sonogram.
• the color-flow imaging modality interrogates a specific region of the body, and displays a real-time image of mean velocity distribution.
• the CFI's are usually shown on top of the dynamic B-mode image.
• nop-7 1 While color flow images display the mean or standard deviation of the velocity of reflectors (i.e., blood cells) in a given region, power Doppler (PD) displays a measurement of the amount of moving reflectors in the area, similar to a B-mode image's display of the total amount of reflectivity.
• a PD 5 image is an energy image in which the energy of the flow signal is displayed. These images give no velocity information but only show the location of flow.
• the spectral Doppler or spectral sonogram modality utilizes a pulsed- wave system to interrogate a single range gate and displays the velocity
• This sonogram can be combined with a B- mode image to yield a duplex image.
• the top side of the display shows a B-mode image of the region under investigation, and the bottom > shows the sonogram.
• the sonogram can also be combined with the CFI image to yield a triplex image.
• CD images consist of Doppler information that can be color- encoded and superimposed on a B-mode gray-scale image.
• Color-flow imaging is a mean velocity estimator. There are two different techniques in computing the mean velocity. First, in a pulsed
• Doppler system fast fourier transformer can be used to yield the velocity distribution of the region of interest, and both the mean and variance of the velocity profile can be calculated and displayed as a color flow image.
• FFTs Doppler system fast fourier transformer
• the other approach uses a one-dimensional auto correlation.
• the spatial mean velocity is determined by the mean angular frequency.
• P( ⁇ ) is the power-spectral density of the received, demodulated signal.
• the inverse Fourier transform of the power-spectral density is the autocorrelation:
• the mean velocity estimator can be reduced to an estimation of the autocorrelation and the derivative of the autocorrelation.
• f p ⁇ f is the pulse repetition frequency
• N c are the number of lines used in autocorrelation estimator. In practice, more then 2 lines are used to improve the signal-to-noise ratio. Data from several RF lines are 20 needed in order to get useful velocity estimates by the auto-correlation technique. Typically, between 8 and 16 lines are acquired for the same
• the CFI pulses are interspersed between the B- mode image pulses.
• CFI pulses it is known that a longer duration pulse 5 train gives an estimator with a lower variance, however, good spatial resolution necessitates a short pulse train. Consequently, a separate pulse train must be used for the B-mode image, because the CFI pulse train is too long for high-resolution, gray-scale images.
• CFI the velocity estimator is given by Eq. 10 (5). This can be computed by serial processing, since the arrival of samples for a new line results in the addition of the new data to an already calculated sum. Four multiplications, three additions, and a subtraction are performed for each range gate and each new line. Stationary echo cancellation is also performed for each new sample. A filter with N e , coefficients necessitates
• N ops ⁇ 2N e + 2)Mf 0 (1)
• Mf 0 is the number of data samples per second. This is a
• N ops ⁇ nN e + 2)Mf, Ne ⁇ N " (8)
• N f is the number of CFI lines per estimate
• N B is the number of B-mode image lines interspersed between CFI lines
• ⁇ denotes the 25 effective time spent on acquiring useful data
• CFI Color Flow Imaging
• PD Power Doppler imaging
• CF imaging displays the mean or standard deviation of the velocity of reflectors (e.g., blood cells) in a given region
• PD displays a measurement of the density of moving reflectors in the
• Power Doppler is akin to a B-mode image with stationary reflectivity suppressed. This is particularly useful for viewing moving particles with small cross- sectional scattering, such as red blood cells.
• the total Doppler power can be expressed as the integral of the power-spectral density over all angular frequencies
• the integrated power in the frequency domain is the same as the integrated power in the time domain and hence the power Doppler can be computed from either the time-domain or the frequency- domain data, hi either case, the undesired signals from the surrounding tissue, such as the vessel walls, should be removed via filtering.
• the PD can be computed in software running on a microprocessor; similar to the computation of the CFI processing described above.
• Parallel computation units such as those in the Intel Pentium TM and Pentium fl's MMX coprocessors, allow rapid
• DSP Digital Signal Processor
• the frequency content of the Doppler signal is related to the velocity distribution of the blood. It is common to devise a system for estimating blood movement at a fixed depth in tissue. A transmitter emits an ultrasound pulse that propagates into and interacts with tissue and blood. The backscattered signal is received by the same
• a display of the distribution of velocities can be made by Fourier transforming the received signal and showing the result. This display is also called a sonogram. Often a B-mode image is presented along with the sonogram in a duplex system, and the area
• range gate 30 of investigation, or range gate, is shown as an overlay on the B-mode image.
• the placement and size of the range gate is determined by the user. In turn,
• the range gate length determines the area of investigation and sets the length of the emitted pulse.
• the calculates spectral density is displayed on a screen with frequency on the y-axis and time on the x-axis.
• the intensity of a pixel on 5 the screen indicates the magnitude of the spectmm; thus, it is proportional to the number of blood scatterers moving at a particular velocity.
• the range gate length and position are selected by the user. Through this selection, both emitted pulse and pulse repetition frequency are determined.
• the size of the range gate is detemiined by the length of the 10 pulse.
• the pulse duration is
• the gate duration determines how rapidly pulse echo lines can be acquired. This is referred to as the pulse-repetition frequency or
• d 0 is the distance to the gate.
• d 0 is the distance to the gate.
• HZ pulse is used, for probing a blood vessel lying at a depth of 3 cm with a 10 ms observation time.
• the pulse-repetition frequency is
• the sono graph computation can be carried out in software running on a microprocessor (similar to the computation of the CFI processing described above).
• Parallel computation units such as those inside the Intel Pentium TM and Pentium IPs MMX 5 coprocessors, allow rapid computation of the required FFT functions. All three velocity estimation systems can be implemented in software on current microprocessors, such as the Intel Pentium, or digital signal processors (DSP).
• Stabilized microbubbles are used for ultrasound contrast imaging because of their unique acoustic properties compared to biological tissues. They present superior backscattering and nonlinear behavior, and fragility upon exposure to ultrasound. A number of ultrasound imaging modalities have been created to exploit these features.
• a technique using the second harmonic relies on the fact that bubbles generate harmonics of the transmitted frequency at a level much higher than the harmonics generated by the tissues. By creating images from the signal received at twice the transmitted frequency, high image contrast is achieved between regions with and without bubbles. A problem with this imaging
• a short pulse typically used in B-mode imaging
• the transmitting and receiving frequencies overlap, contaminating the harmonic image with the fundamental frequency.
• the pulse inversion method (also called wideband harmonic imaging 5 or dual pulse imaging), solves the problem of overlapping frequencies observed with the second harmonic technique.
• Each scan line is formed by summing the signals received from two ultrasound pulses, where the second pulse is inverted and slightly delayed relative to the first. This procedure cancels the response of all linear scatters (if there is no tissue movement
• any bubble displacement adds an additional, signal, resulting in velocity-dependent enhancement.
• the stimulated acoustic emission method typically involves color Doppler with the transmitting
• a preferred embodiment of the invention employs a spatial filter in providing a power doppler image, for example. This spatial or high pass
• DOC;! ⁇ -54- filter can also be used effectively with a contrast agent to further differentiate between blood flow and the surrounding vessel or artery.
• a preferred embodiment of the invention employs a spatial filter in providing a power doppler image, for example.
• This spatial or high pass filter can also be used effectively with a contrast agent to further differentiate between blood flow and the surrounding vessel or artery.
• the ratio of the power of the signal before and after the filter provides a data set yielding clear images of moving fluid within the body.
• FIG. 13 shows the top-level screen of a graphical user interface (GUT) for controlling the ultrasonic imaging system.
• GUT graphical user interface
• a selection bar 702 allows the operator to select the active focus areas of the screen.
• An image area 704 displays the ultrasonic image of the subject area.
• a patient infomiation area 706 displays information about the subject from whom
• a Time Gain Compensation area 708 provides feedback about time gain compensation, described further below.
• a control bar 710 allows qualitative and quantitative selection of ultrasonic imaging operations, as will be described further below with respect to FIGS. 15A and l5B.
• FIG. 14 shows the unitary, directional keypad which provides a single operating position from which to control the ultrasonic imaging operations.
• an up arrow key 712 and a down arrow key 714 allow a user to scroll through the qualitative ultrasonic imaging operations of the system, as will be described further below.
• the quantitative parameters may be in a range of discrete values, or may span a
• a control key 720 employed in conjunction with the up arrow key 712 or down arrow key 714 allows an operator to toggle between two control tabs depicted in FIGS. 15A and 15B, as will be described further below. Since all keys employed in controlling and selecting the ultrasonic 5 imaging operations are accessible from a common operating position, an operator may focus on the ultrasonic image of the subject and on the handheld probe, and need not be distracted by unwieldy controls. Traditional directional keypads allow only directional control to be applied by the directional keypads, and do not allow both qualitative and quantitative
• FIGS. 15 A and 15B show qualitative and quantitative selection of ultrasonic imaging operations via invoking the unitary directional keypad of FIG. 14. Referring to FIG. 15 A, ultrasonic imaging operations applicable to
• the scanning operations are directed active acquisition of real-time, dynamic ultrasonic image data, and are typically applied as the hand-held probe is manipulated over the subject imaging area.
• a size operation 722 sets a series of predetermined defaults for other ultrasonic imaging operations. A small, medium, or large subject may be selected via
• a depth operation 724 allows selection of a depth parameter via the arrow keys 716, 718.
• Focus is controlled by a focus 726 operation.
• Gain 728 control adjusts the TGC for all TGC settings 730a-730h.
• ultrasonic imaging operations applicable to processing are shown.
• the processing operations may be applied to static real-time or frozen images.
• An inversion operation is controlled by the inversion 732 selection, and rotates the image via the arrow keys 716, 718
• FIG. 16 shows a state diagram depicting transition between the ultrasonic imaging operations depicted in FIGS. 15A and 15B.
• the Tab 746 operations are selected via the up and down arrow keys 712, 714 and transition according to the following state sequence: size 600, depth 602, focus 604, Gain 606 and TGC degrees 608, 610, 612, 614, 616, 618, 620 and 622.
• the Tab 2 operations are selected according to the following sequence: invert 624, palette 626, smoothing 628,
• the scanning operations shown in FIG. 15 A are displayed on Tab 1 746, as shown in FIG. 13.
• the processing operations shown in FIG. 15B are
• control is toggled between Tab 1 746 and Tab 2 748 using a combination of the control key 720 and either the up or down arrow keys 712, 714, as shown by dotted lines 638a and 638b.
• Another embodiment of the invention involves providing the user with an intuitive and simple way to use interface, and with the ability to quickly and automatically set imaging parameters based on a software module. This enables general medical personnel with limited ultrasound experience to
• the "Quick Look” feature provides the user with a very simple mechanism of image optimization. It allows the user to simply adjust the image so as to obtain appropriate diagnostic image quality with one push of one button.
• the benefits of programmed image parameters are many. The user
• the procedure involves the use of predefined histograms. Separate 5 hostograms are provided for different anatomical structures that are to be examined. The user chooses a structure, similar to the existing method of choosing a preset. Once the stmcture is chosen, the user places the transducer on the area of interest in the scanning window. At that time, pressing the selected control button triggers the system to adjust the system
• a preferred embodiment provides an independent control which allows the user to adjust for ambient lighting changes, hi many applications the programmed parameters gets the user very close, but they may choose to fine tune the contrast and brightness.
• the integrated probe system 24 has the front
• PDA personal digital assistant
• the PDA 9, such as a Palm Pilot device, or other hand-held computing device is a remote display and/or recording device 9.
• the front end probe 3 is connected to the host computer 5 by the communication link 40 that is a wired link.
• 25 computing device is connected to the PDA 9 by a communication link or interface 46 that is wireless link 46.
• the integrated ultrasound probe system 20 in the embodiment described has a Windows-based host computer 5
• the system can leverage the extensive selection of software available for the Windows operating system.
• connections through the communication links or interfaces 40 and 46 can be either wired through an Ethernet or wireless through a wireless 5 communication link such as IEEE 802.11a, IEEE 802.11b, Hyperlink or HomeRF, etc.
• FIG. 17A shows a wired link for the communication link 40 and a wireless link for the communication link 46.
• Alternative embodiments and protocols for wired links are described above with respect to FIG. 1. It is recognized that other wired embodiments or protocols can be used.
• the wireless communication link 46 can be of various different protocols, such as, an RF link which may be implemented using all or parts of a specialized protocol, such as the Bluetooth system protocol stack.
• the Bluetooth protocol uses a combination of circuit and packet switching. Slots can be reserved for synchronous packets. Bluetooth can support an
• Each synchronous (voice) channel support a 64 kb/s synchronous (voice) channel in each direction.
• the asynchronous channel can support maximal 723.2 kb/s asymmetric, or 433.9 kb/s symmetric.
• the Bluetooth system consists of a radio unit, a link control unit, and a support unit for link management and host terminal interface functions.
• the link controller carries out the baseband protocols and other low-level link routines.
• the Bluetooth system provides a point-to-point connection (only two
• the channel is shared among several Bluetooth units. Two or more units sharing the same channel form a piconet.
• One Bluetooth unit acts as the master of the piconet, whereas the other units act as slaves. Up to seven slaves can be active in a piconet.
• the Bluetooth link controller has two major states: STANDBY and
• the substates are interim states that are used to add new slaves to a piconet.
• the link may also be implemented using, but not limited to, Home RF, or the IEEE 802.11 wireless LAN specification.
• IEEE 802.11 wireless LAN specification see the Institute of Electrical and Electronic Engineers (IEEE) standard for Wireless LAN incorporated herein by reference. IEEE standards can be found on the World Wide Web at the Universal Resource Locator (URL) www.ieee.org.
• IEEE standard 802.11b provides a
• the wireless link 46 can also take on other fomis, such as, an infrared communications link as defined by the Infrared Data Association (IrDA).
• IrDA Infrared Data Association
• FIG. 17B shows the communication link 40 between the probe 3 and the host computer 5 as a wireless link.
• the communication link 46 between the host computer 5 and the PDA 9 is shown as a wired link.
• the integrated probe system 24 of FIG. 17C has wireless links for
• the remote display and/or recording device 9 of the integrated probe system 24 of FIG. 18 is a remote computing system 26.
• the remote 5 computing system 26 in addition to having remote display and/or recording capability can also control the probe 3.
• the communication link 46 is shown as a wireless link.
• the communication link 40 between the probe 3 and the host computer 5 is shown as a wired link.
• An example of remote control is using a wearable computer (such as
• a portable-networked ultrasound system can be configured weighing less than 2.5 pounds.
• a program similar to Microsoft NetMeeting a real-time connection between a remote PC and the wearable
• the remote host can monitor all interactions with the wearable computer, including real-time ultrasound imaging (at display rates up to approximately 4 frames per second). NetMeeting can also be used to "take control" of the wearable computer and manage the ultrasound session from the remote personal computer in real time.
• real-time ultrasound imaging at display rates up to approximately 4 frames per second.
• NetMeeting can also be used to "take control" of the wearable computer and manage the ultrasound session from the remote personal computer in real time.
• images and loops that are archived to the hard disk on the wearable computer can be transferred at 108 Mbps to the host computer.
• real time ultrasound diagnoses can be performed and relayed to a remote sight at speeds that rival a hardwired 100 Mbps LAN.
• FIG 19 illustrates an integrated probe system 24 that has a hub 48 for
• the communication link 50 from the hub 48 to the remote devices are shown both as wireless and wired links. It is recognized that a completely wired Ethernet can be used, hi the alternative, with a wireless transceiver and port in each of the computers (remote device) 9, a wireless

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