User`s manual

CLARION M10 SERIES STRUCTURE
M10 SERIES USER’S MANUAL PAGE 16
a manner that direct RF leakage between the two antennas is reduced
by an intervening metal object or shielding wall.
2.3.12 CHANNEL ACCESS PROTOCOL
The M10 provides for adaptive P-CSMA
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by using a sequence of P values.
These are loosely tied to the transmission attempts, in that the P values in
the sequence correspond to the attempt number, but any successful receive
resets to P0 for the next attempt; if that attempt fails, the sequence of P
values is resumed according to which attempt is in progress. (P is a power
of two, up to 256.)
1
On Ethernet both carrier sensing and collision detection are simple processes. For any
radio channel the ability to detect collisions is lost; in addition, for a spread-spectrum
system with changing codes (for security) the ability to perform carrier sensing is
limited to acquisition of the preamble portion of a transmission. The channel-access
protocol (CAP) employed in the M10 is called P-persistent CSMA.