Atlantis NetFly UP3 WN, Manual

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members of the
wireless network?
Refer to the game’s user guide for more
information.
What is Spread
Spectrum?
Spread Spectrum technology is a wideband radio
frequency technique developed by the military for
use
in reliable, secure, mission-critical
communications systems. It is designed to trade off
bandwidth efficiency for reliability, integrity, and
security. In other words, more bandwidth is
consumed than in the case of narrowband
transmission, but the trade-off produces a signal
that is, in effect, louder and thus easier to detect,
provided that the receiver knows the parameters of
the spread-spectrum signal being broadcast. If a
receiver is not tuned to the right frequency, a
spread-spectrum signal looks like background noise.
There are two main alternatives, Direct Sequence
Spread Spectrum (DSSS) and Frequency Hopping
Spread Spectrum (FHSS).
What is DSSS? What is
FHSS? And what are
their differences? Frequency-Hopping Spread-Spectrum (FHSS) uses a
narrowband carrier that changes frequency in a
pattern that is known to both transmitter and
receiver. Properly synchronized, the net effect is to
maintain a single logical channel. To an unintended
receiver, FHSS appears to be short-duration impulse
noise. Direct-Sequence Spread-Spectrum (DSSS)
generates a redundant bit pattern for each bit to be
transmitted. This bit pattern is called a chip (or
chipping code). The longer the chip, the greater the
probability that the original data can be recovered.
Even if one or more bits in the chip are damaged
during
transmission, statistical techniques
embedded in the radio can recover the original data
without the need for retransmission. To an
unintended receiver, DSSS appears as low power
wideband noise and is rejected (ignored) by most
narrowband receivers.
Would the information
be intercepted while WLAN features two-fold protection in security. On
the hardware side, as with Direct Sequence Spread