Monday, February 4, 2013

Standar Kecepatan IEEE 802.11 a/b/g/n sumber website resmi


  •  Setandar Kecepatan IEEE 802.11 a/b/g/n berdasar jarak: klik link  Berisikan artikel mengenai standar kecepatan IEEE 802.11 wlan dengan jarak tertentu, misal 5mt   berapa kecepatanya, 10m berapa kecepatanya. satuan yang digunakan dalam satuan feet. Range dalam feet.


  • Standar Kecepatan IEEE 802.11 a/b/g/n sumber website resmi, sebagai berikut :
Referensi : http://www.ni.com/white-paper/7131/en
  • 802.11a: The signal is transmitted at 5 Ghz and can move up to 54 megabits of data per second.  It uses Orthogonal Frequency-Division Multiplexing (OFDM), which is an efficient coding technique that splits the radio signal into several sub signals before they reach a receiver.  This greatly reduced interference between signals.
  • 802.11 b: This is the slowest and least expensive existing standard.  Initially, 802.11b was the most popular standard because of its cost, but as faster standards get less expensive, 802.11b is losing popularity.  This standard transmits in the 2.4 Ghz frequency bandwidth.  It can transmit up to 11 megabits of data per second and it uses Complimentary Code Keying (CCK). 802.11b is based on Complementary Code Keying (CCK).
  • 802.11g: 802.11g transmits at 2.4 Ghz like 802.11b but at faster rates.  It can transmit upto 54 Mbits per second.  Similar to 802.11a, 802.11g transmit faster because it uses OFDM instead of CCK.
  • 802.11n: This is the most recent standard and is becoming commercially available.  This standard significantly improves speed and range.  For instance, although 802.11g theoretically transmits 54 Mbits of data per second, it only achieves real-world speeds of about 24 Mbits per second because of network congestion.  802.11n, however, can transmit as high as 140 Mbits per second.

Sumber 2:
Referensi  Lain: http://compnetworking.about.com/
  • ·          802.11
       In 1997, the Institute of Electrical and Electronics Engineers (IEEE) created the first WLAN standard. They called it 802.11 after the name of the group formed to oversee its development. Unfortunately, 802.11 only supported a maximum network bandwidth of 2 Mbps - too slow for most applications. For this reason, ordinary 802.11 wireless products are no longer manufactured.
  • ·            802.11a
        802.11a supports bandwidth up to 54 Mbps and signals in a regulated frequency spectrum around 5 GHz. This higher frequency compared to 802.11b shortens the range of 802.11a networks. The higher frequency also means 802.11a signals have more difficulty penetrating walls and other obstructions.
  • ·            802.11b
        IEEE expanded on the original 802.11 standard in July 1999, creating the 802.11b specification. 802.11b supports bandwidth up to 11 Mbps, comparable to traditional Ethernet.
  • ·             802.11g
        In 2002 and 2003, WLAN products supporting a newer standard called 802.11g emerged on the market. 802.11g attempts to combine the best of both 802.11a and 802.11b. 802.11g supports bandwidth up to 54 Mbps, and it uses the 2.4 Ghz frequency for greater range. 802.11g is backwards compatible with 802.11b, meaning that 802.11g access points will work with 802.11b wireless network adapters and vice versa.
  • ·            802.11n
        The newest IEEE standard in the Wi-Fi category is 802.11n. It was designed to improve on 802.11g in the amount of bandwidth supported by utilizing multiple wireless signals and antennas (called MIMO technology) instead of one.
        When this standard is finalized, 802.11n connections should support data rates of over 100 Mbps. 802.11n also offers somewhat better range over earlier Wi-Fi standards due to its increased signal intensity. 802.11n equipment will be backward compatible with 802.11g gear.





0 comments:

Post a Comment

ShareThis

 


let's learn to share Copyright © 2010 Check Google Page Rank