802.11n flavours explained

Most 802.11n enabled Access Points out there advertise themselves as follow: 2x3:2, 2x2:2. Ever wonder what these numbers mean?
Well here is what I make out from them:

You will find 802.11n with the following flavors:

1x1:1

1x2:2

2x2:2

2x3:2

3x3:2

Where:

TxR:S

T - Transmit

R - Receive

S - Spatial

The spatial is your "money". Each spatial equates to 150mb, so you will see 3x3:3 equates to 450 mb.Thats why with Cisco APs and others, you will only ever get 300 with xXx:2.

Let me add further, 2 on the transmit means you will use no more than 2 antennas to TX on. 3 on the receive means you will use 3 antennas to rx on. The spatial is your streams. if you have a 2 stream AP, that means its the most number of streams network will have, that too if your environment is favourable to use 2 streams, just because it can do 2, doesn't mean it will always do 2.

802.11n although by standard could support 600 4x4:4, its VERY unlikely we will see that in the enterprise. Atheros mentioned they will not support development of the 4x4:4 chip. Why you ask ? They said that 802.11ac should be a quick ratification. 802.11ac, you will be able to do 8x8:8, hence GIG over wireless.

Hope it helps.

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