Atlantis A02-PL303-WN, Руководство пользователя

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A.6 Wireless
Question Can I run an application from a remote computer over the
wireless network?
Answer This will depend on whether or not the application is designed to
be used over a network. Consult the application’s user guide to
determine if it supports operation over a network.
Question Can I play computer games with other members of the wireless
network?
Answer Yes, as long as the game supports multiple players over a LAN
(local area network).
Refer to the game’s user guide for more information.
Question What is Spread Spectrum?
Answer 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).
Question What is DSSS? What is FHSS? And what are their differences?
Answer 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