User`s manual

CLARION M10 SERIES STRUCTURE
M10 SERIES USER’S MANUAL PAGE 7
2.3 Principles of Operation
2.3.1 UPLOAD PROCESS
The Upload is defined as a data flow from an Ethernet device to the M10.
During Upload, it provides the following:
• Detection of preamble of the Ethernet frame followed by the
frame sync pattern.
• Suppression of the Ethernet preamble and frame sync for RF
transmission. (These portions of the frame are meaningless for
wireless transmission).
• Generation of a Collision signal if an Upload commences
while the AUI interface is busy; generation of the busy
Collision is selected through configuration setup. This enables
the M10 to force the Ethernet card into its exponential back-off
algorithm for flow control. If generation of the Collision is not
selected, then no Collision is generated but Uploads are
ignored.
• Generation, when enabled through the configuration setup, of the
SQE (Signal Quality Error) test signal toward the MAU port.
• FEC-encoding, when FEC is enabled through configuration
setup.
• Generation of header information (RF MAC and RF physical
layer).
• Spread-spectrum carrier sense before transmission, with
preference given to reception. The M10 senses signals after
correlation, meaning that interference, such as microwave ovens
and different kinds of wireless LAN systems, cannot be sensed.
• Data and spread-spectrum modulation onto a carrier of 2.4 GHz
and RF transmission.