FujiFilm SonoSite sII Service Manual page 30

Acquisition
RF
subsystem
Bus
Transducer
Pulser voltage
Figure 4.1 SonoSite SII High-Resolution Ultrasound System Block Diagram
The Transducer elements convert the pulser voltage to acoustic energy during the transmit portion of the
ultrasound acquisition cycle. The elements convert the acoustic echo to voltage in the receive portion of the
acquisition. The voltage developed on the transducer elements is sensed by the acquisition subsystem. The
system transducers have 64 to 256 elements.
The Acquisition Subsystem consists of the beamformer and interface to the transducer. The beamformer
controls the timing of the transmit pulses to focus the acoustic beam. The beamformer amplifies the
low-level received echos and controls the receive focusing. The system beamformer transmits on up to 128
elements and receives on 64 elements.
The Processing Subsystem includes capabilities for interfacing with the beamformer and performing high
speed processing. The processing subsystem demodulates, filters, detects, and compresses the signal
supplied by the beamformer into display information.
The Display Subsystem converts the detected ultrasound data into picture elements (pixels). The software
user interface graphics are combined with the ultrasound information and converted to a video stream. The
external video port supports NTSC and PAL format.
The Control Subsystem consists of the central processing unit, program and video memory, permanent
image storage and retrieval memory, external communication interface ports, and connection to the user
interface keys. The control software includes the acoustic power and intensity software subsystem, power
group monitors, and a beamformer monitor. This software guarantees a level of patient safety by ensuring
the system is operating within acoustic power and intensity limits.
The User Interface Subsystem represents the software interface and form factor. The software interface
is the interaction between the user and the screen layout components. The form factor is the type of physical
buttons, location, and grouping of the buttons and the device size, shape, and weight. Dedicated controls
are for high usage activities and grouped according to the user workflow.
24 Chapter 4: System Overview
Processing Display
AQ
subsystem subsystem
Bus
Control Bus
External video to
monitor, printer
Video
User
interface
IrDA
Control
subsystem
Serial Bus
Power
subsystem
Display power
Logic power
Power
adapter
External power
Battery
pack
assembly