GE HEALTHCARE
DIRECTION FC091194, REVISION 11 VIVID 7 SERVICE MANUAL
Chapter 5 - Components and Functions (Theory) 5 - 61
5-3-21 Radio Frequency Interface Board, RFI
5-3-21-1 General Description
The RFI board was introduced into the manufacturing in the 2nd half of 2003 together with the Front-
End Processor version 2 (FEP2).
The functionality of the following boards are either implemented on the RFI board or on the BEP:
• Front-End Controller board
• RF & Tissue board
• Spectrum Doppler Processor board (some filtering done on RFI, the rest is done by BEP).
• Image Port board.
Tasks Done by the RFI board:
• System Master Clock generator
• Transmitter Control
• ATGC Control
• Receive Focusing Control
• Analog Test Signal Generator
• High Voltage Control and supervision
• Probe Sensing
• Control of Relay Board
• Doppler Audio D/A conversion
• Temperature Sensing for TEE probes
• Step Motor Control for TEE probes
• Temperature Sensing for circulated air
5-3-21-2 Signal Flow
The digitized signals from the Beam Formers, are connected to the RFI module. The Digital Signal
Processor on the RFI board together with software on the BEP, performs the adequate signal
conditioning for the different data types; Tissue, Doppler and Color Flow.
In addition, Doppler Audio Processing is done by the RFI board. The Doppler Spectrum Processing is
done by the BEP.
The RFI extracts Tissue Data, Spectrum Data and IQ & Color Data from the digital data stream on its
input and it also performs RF filtering and different types of Tissue Processing.
5-3-21-3 RF Processing
Different types of RF processing is performed depending on later usage of the data;
• RF Demodulation
• Digital Time Gain Compensation
• Filtering
• Decimation (data that are not needed for the processing, is removed)
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