![]() ![]() In more than 100 buildings on MIT's Cambridge, Mass., campus, as many as 3,200 access points running older 802.11a/b/g protocols will be replaced with 802.11n devices in the next 12 to 16 months, said Chris Murphy, a networking engineer at the university. MIT and a medical center based in Alabama are beginning to deploy faster wireless 802.11n access points from Cisco Systems Inc. Ofcourse we will have problems if they are using quite different frequencies as the antennas ore optimised to range of frequencies, this is something that has to be seen. In fact the same is applicable for WiMAX as it supports MIMO and OFDM. The new LTE handsets will have advantage of easily integrating this 802.11n technology and the same antennas can be reused. 802.11 family uses OFDM which is the same technology being adopted by LTE. The main difference in 802.11n, compared to previous generation of 802.11 is that there is a presence of MIMO. In a mixed-mode system, it’s generally best to utilize a dual-radio access point and place the 802.11b/g traffic on the 2.4 GHz radio and the 802.11n traffic on the 5 GHz radio.Ī lot of phones are coming with inbuilt WiFi (or 802.11 a/b/g) and this WiFi is a must on Laptops or they wont sell. Consequently, it may be more practical to operate a mixed 802.11b/g/n network until 802.11n hardware becomes more prevalent. An all-802.11n network may be impractical, however, as existing laptops generally have 802.11b/g radios which must be replaced if they are to operate on the network. The 5 GHz band has substantial capacity due to many non-overlapping radio channels and less radio interference as compared to the 2.4 GHz band. ![]() To achieve maximum throughput a pure 802.11n 5 GHz network is recommended. Note that there is 802.11n PHY and 802.11n MAC that will be required to acheive 540Mbps. The system supports basebands width of 20 or 40MHz. The N system is strongly based on the IEEE 802.11e QoS specification to improve bandwidth performance. MIMO uses multiple transmitter and receiver antennae to allowfor increased data throughput through spatial multiplexing and increased range by exploiting the spatial diversity and powerful coding schemes. IEEE 802.11n builds upon previous IEEE 802.11 standards by adding MIMO. IEEE 802.11n will probably offer a better operating distance than current networks. In the N option, the real data throughput is estimated to reach a theoretical 540 Mbps (which may require an even higher raw data rate at the physical layer), and should be up to 100 times faster than IEEE 802.11b, and well over ten times faster than IEEE 802.11a or IEEE 802.11g. multiple-input multiple-output and space time coding).
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |