on 07-06-2013 01:25 PM
IEEE 802.11n is builds on previous 802.11 standards by adding multiple-input multiple-output (MIMO) and 40 MHz channels to the PHY (physical layer), and frame aggregation to the MAC layer.
Factors affecting wireless
Because wireless signals travel through the atmosphere, they are sensitivity to different types of interference compare to wired network.
1) Physical objects: The number of walls the Wireless signal can pass through is determines by density of the materials used in a building’s construction. Concrete and steel walls are difficult for a signal to pass through. These structures will weaken or at times completely prevent wireless signals.
2) 2.4Ghz Frequency Interference:
a. Cordless Phone - operate the same frequency which the Wi-Fi standards and this can cause a significant decrease in speed, or sometimes the total blocking of the Wi-Fi signal.
b. Microwave Oven - operate by emitting a very high power signal in the 2.4 GHz band and often emit a very "dirty" signal over the entire 2.4 GHz band.
c. Wireless Routers – Wireless Network that share the same wireless channel will reduce the wireless speed performances.
3) Shared bandwidth: The bandwidth of wireless network is shared among all the wireless users, so the more users you have the slower network speed is in the network. Especially downloading Torrent will cause users unable to surf internet properly.
4) Distance: If you sit near to wireless router or access point, you will get high and good network speed but if another person is sitting far from the wireless router or access point, the network speed of both computers will be dropped drastically.
5) Mixed Network (802.11b/g/n): In the network by connecting 802.11n wireless adapter alone you can get good network speed, however once an 802.11g or 802.11b user joined the network, your network connection speed may be slowed by half or more.
6) Locations: The location where an AP or wireless router is placed also makes the different. Place the devices in higher ground to reduce the impact of physical objects.
Below is the Wireless Obstacles Table:
Actions to improve wireless access
1) Wireless Settings for Best throughput between PC and Router:
a. 802.11 Mode: Mixed 802.11 n/b/g
b. Channel Width: 20/40Mhz (Auto)
c. WPA Mode: Auto (WPA or WPA2)
d. Cipher Type: AES
1) Data Point (Access Point)
a) Deploying Access Point around your home, particularly in existing areas of poor or no coverage reduces the average distance between a wireless device and its nearest access point and increases the average speed.
Basic maintenance and troubleshooting of wireless network
Things to look out for when the wireless network start to get “Slow” and the result will still depend on individual environments.
1) Change the wireless channel to less “Crowded” channels.
2) Or reboot the router if “Enable Auto Channel Scan” is enable, the router will scan and assign a new channel during the boot up.
3) Or move the wireless network frequency from 2.4GHz to 5 GHz for 802.11a/n.
*Please make sure all the wireless clients (PC) can also support 5GHz otherwise users can only see 2.4GHz SSID.
4) Lastly, user can reset the device to factory default setting by
a. Hardware Reset
With the router powered on, use a paperclip to hold the button down for 10 seconds.
b. Web GUI Reset
Tools > System
*Factory reset will erase all the present settings on the router.