802.11N MIMO的spatial stream

802.11N MIMO的spatial stream指的是802.11N所使用的天線中所形成的傳輸空間，這些空間分成transmit、receive、transmit and receive，每一台AP所能夠使用的傳輸空間不同，大致上可分為以下幾種:

1x1:1 - 1 transmitter, 1 receiver, can transmit or receive 1 spatial stream

1x2:1 - 1 transmitter, 2 receivers, can transmit 1 spatial stream, but receive 2 spatial streams

2x2:2 - 2 transmitters, 2 receivers, can transmit and receive 2 spatial streams

2x3:2 - 2 transmitters, 3 receivers, can transmit and receive 2 spatial streams

3x3:2 - 3 transmitters, 3 receivers, can transmit and receive 2 spatial streams

3x3:3 - 3 transmitters, 3 receivers, can transmit and receive 3 spatial streams

4x4:4 - 4 transmitters, 4 receivers, can transmit and receive 4 spatial streams

不同的傳輸空間所能夠提供的傳輸速度大概有300 Mbps (2x2:2), 450 Mbps (3x3:3), and 600 Mbps (4x4:4).