|
MIMO stands for Multiple-Input Multiple-Output. It is generally used in conjunction with IEEE* 802.11n, however, it can be used with other 802.11 technologies. MIMO is sometimes called spatial diversity because it uses multiple spatial channels for data transmission and reception. Either the station (mobile device) or the Access Point (AP) need to support MIMO in order for it to be implemented.
Advantages of MIMO are increased wireless range and performance. An 802.11n station connected to a legacy 802.11g AP will be able to connect at higher speeds at a greater distance. For instance, if a legacy station connecting to the AP from a distance of 25ft had a speed of 1Mbps, with 802.11n MIMO the station could have a speed of 2Mbps. The range of the 2Mbps has increased allowing the user to stay connected at a further distance.
When a radio sends a signal it is reflected creating multiple copies of the radio signal. Each one of these copies is a spatial stream. Current or legacy systems using Single-Input Single Output (SISO) can only send or receive a single spatial stream at one time. MIMO allows multiple antennas to send and receive multiple spatial streams at the same time. This allows antennas to transmit and receive simultaneously.
Legacy AP to Legacy Client - only one spatial stream sent and received
MIMO AP to MIMO Client - multiple spatial streams sent and received simultaneously
This applies to:
| 
