TP-LINK TL-WN827N ユーザーズマニュアル

  

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802.11n - 802.11n builds upon previous 802.11 standards by adding MIMO (multiple-input 

multiple-output). 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 Alamouti coding. The Enhanced Wireless Consortium 

(EWC) [3] 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 

802.11b  - The 802.11b standard specifies a wireless networking at 11 Mbps using 

direct-sequence spread-spectrum (DSSS) technology and operating in the unlicensed radio 

spectrum at 2.4GHz, 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-sequence 

spread-spectrum (DSSS) technology, using OFDM modulation and operating in the unlicensed 

radio spectrum at 2.4GHz, and backward compatibility with IEEE 802.11b devices, and WEP 

encryption for security. 

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. 

DSSS (Direct-Sequence Spread Spectrum) - 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 for 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). 

FHSS  (Frequency  Hopping  Spread  Spectrum)  - FHSS continuously changes (hops) the carrier 

frequency of a conventional carrier several times per second according to a pseudo-random set of 

channels. Because a fixed frequency is not used, and only the transmitter and receiver know the 

hop patterns, interception of FHSS is extremely difficult. 

Infrastructure Network - An infrastructure network is a group of computers or other devices, 

each with a wireless adapter, connected as an 802.11 wireless LAN. In infrastructure mode, the 

wireless devices communicate with each other and to a wired network by first going through an 

access point. An infrastructure wireless network connected to a wired network is referred to as a 

Basic Service Set (BSS). A set of two or more BSS in a single network is referred to as an 

Extended Service Set (ESS). Infrastructure mode is useful at a corporation scale, or when it is 

necessary to connect the wired and wireless networks.   

Spread Spectrum - Spread Spectrum technology is a wideband radio frequency technique