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AC1900 Dual Band Wi-Fi USB Adapter
User Manual
RNX-AC1900UB
Appendix B: Glossary
•
802.11b
- The 802.11b standard specifies a wireless product networking at 11
Mbps using direct-sequence spread spectrum (DSSS) technology and operating
in the unlicensed radio spectrum at 2.4 GHz and WEP encryption for security.
802.11b networks are also referred to as Wi-Fi networks.
•
802.11g
- Specification for wireless networking at 54 Mbps using direct-sequenc
spread spectrum (DSSS) technology, using OFDM modulation and operating in
the unlicensed radio spectrum at 2.4 GHz. Backward compatible with IEEE
802.11b devices and WEP encryption or security.
•
802.11n
- Builds upon previous 802.11 standards by adding multiple-input
multiple-output (MIMO). MIMO uses multiple transmitter and receiver antennas
to allow for increased data throughput via spatial multiplexing and increased
range by exploiting the spatial diversity, perhaps through coding schemes like
Alamout i coding. The Enhanced Wireless Consortium (EWC) was formed to
help accelerate the IEEE 802.11n development process and promote a
technology specification for interoperability of next-generation wireless local area
networking (WLAN) products.
•
Ad Hoc Network
- An ad hoc network is a group of computers, each with a
Wireless Adapter, connected as an independent 802.11 wireless LAN. Ad hoc
wireless computers operate on a peer-to-peer basis, communicating directly with
each other without the use of an access point. Ad hoc mode is also referred to
as an independent basic service set (IBSS) or as peer-to-peer mode, and is
useful at a departmental scale or SOHO operation.
•
Direct-Sequence Spread Spectrum
(DSSS) - DSSS generates a redundant bit
pattern for all data transmitted. This bit pattern is called a chip (or chipping code).
Even if one or more bits in the chip are damaged during transmission, statistical
techniques embedded in the receiver can recover the original data without the
need of retransmission. To an unintended receiver, DSSS appears as low power
wideband noise and is rejected (ignored) by most narrowband receivers.
However, to an intended receiver (i.e. another wireless LAN endpoint), the DSSS
signal is recognized as the only valid signal, and interference is inherently
rejected (ignored).
