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Wifi Standard 802.11ac

June 22, 2015
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802.11ac is main stream as well as 802.11n.

Because 802.11n has better distance and more power to pass-through wall. But 802.11ac is much fast than 802.11n.

802.11ac Technology Overview:

11n Specification:

  • 2.4 and 5Ghz  Supported
  • Wider channels 40MHz
  • Better modulation 64QAM
  • Additional streams up to 4 streams
  • Beam forming
  • Backwards compatibility, with 11a/b/g

11ac introduces:

  • 5GHz supported
  • Even wider channels 80Mhz and 160 Mhz
  • Better modulation 256 QAM
  • Additional streams up to 8
  • Beam forming
  • Backwards compatibility with 11a/b/g/n

Wider Channels:

80MHz channels is 4.5x faster than 20MHz

 

Now 802.11ac v2 is comming. Also called wave 2. It is expected to be available in 2015.

Here is some highlights of wave 2 802.11ac.

MU-MIMO

  • Use AP MIMO resources more effectively
  • Transmit data to multiple devices simultaneously.

4×4:4SS

  • Benefit of additional stream mostly for MU-MIMO
  • Not anticipating any 4×4:4SS client devices
  • Adds 33% to max datarate

VHT160

  • Double s max datarate
  • Practical problem: only 2 VHT160 channels in entire 5GHz band

Continue reading “Wifi Standard 802.11ac”

How to choose the right channel for your WIFI

August 8, 2013
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There are a lot of things may affect the connection speed of you WIFI. The connection speed between router or AP to your PC or laptop.

One of the most important fact is the channel.

For 2.4GHz, there are 13 channel. 20MHz each channel
1 : 2412MHz
2 : 2417MHz
3 : 2422MHz
4 : 2427MHz
5 : 2432MHz
6 : 2437MHz
7 : 2442MHz
8 : 2447MHz
9 : 2452MHz
10 : 2457MHz
11 : 2462MHz
12 : 2467MHz
13 : 2472MHz
14 : 2477MHz

If choose channel 3, it will cover from 2412MHz to 2432MHz.

One of the best tools to find the right channel is inSSider.
inssider-network

Continue reading “How to choose the right channel for your WIFI”

Switch from Shaw to Telus

August 2, 2012
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From this month, I switch from Shaw to Telus. I am just using Internet and Basic TV. When I am with Shaw, I have to pay $89.49 a month including tax. Which is including Personal TV package and High-Speed Internet.
Now I am using Telus. Including Optik High Speed and Optik TV Essentials. The deal is $19.95 per month plus tax. Total is about $22.35.
It is one year contract.
Let me see the speed first. I am heavily user of Internet. There are 3 Desktops, 2 Laptops, and a lot of wifi devices.
"telus
Essential TV package has about 30 English TV channels. Which also include Free HD channels.

Continue reading “Switch from Shaw to Telus”

WiFi Channel choice

November 1, 2008
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WiFi IEEE 802.11b has a very limited channel (depend on country). In vary pack area with many WiFi Access point not all channel can be use at the same time. In North America, US State and Canada only Channels 1,2,3,4,5,6,7,8,9,10 and 11 are available for usage. In Europe Channel 1,2,3,4,5,6,7,8,9,10,11,12 and 13 can be use. In Japan only Channel 14 available for usage. The usage of each channel depend on country policy.
WiFi with base protocol IEEE 802.11b used Direct Sequence Spread Spectrum (DSSS) Modulation, which mean spectrum width for each usage is 22MHz wide for each station. This mean a station with 2437MHz Channel will be working on frequencies range of 2426MHz to 2448MHz. It will interfere 2 channel below and up of its channel. So effectively only 3 channel can be used without interfering each other which is Channel 1 , 6 and 11.
Channel : Frequency (Bold Channels = Recommended)
1 : 2412MHz
2 : 2417MHz
3 : 2422MHz
4 : 2427MHz
5 : 2432MHz
6 : 2437MHz
7 : 2442MHz
8 : 2447MHz
9 : 2452MHz
10 : 2457MHz
11 : 2462MHz
12 : 2467MHz
13 : 2472MHz
14 : 2477MHz

Continue reading “WiFi Channel choice”

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