Perhaps you are wondering what the numbers that you see on the specifications for wireless access points mean? Numbers such as “2×3” or “3×3”.
These numbers are related to the number of transmitting antennas and receiving antennas that the access point provides. But let’s step back for
a minute. Current Wireless technology is based on the IEEE 802.11 family of standards. There is 802.11n and the newer 802.11ac.
802.11n is the current WiFi standard that your smartphone and laptop probably use and that is used by many of the WiFi APs on
the market today so we are going to our discussion today to 802.11n.
Products based on the 802.11n wireless standard use a technology known as MIMO. MIMO (Multiple Input, Multiple Output) uses multiple
antennas at both the transmitter and the receiver to help increase the throughput and transmit larger amounts of data over
the wireless link.
In the industry, 802.11n products are typically described in terms of their MIMO attributes, denoted by TxR where ìTî is the
number of transmit antennas and ìRî is the number of receive antennas. Further, this standard requires a minimum of two antennas
at the transmit end and two antennas at the receive end. So when you see “2×3 MIMO”, you’ll know that that means the
access point has two antennas at the transmit end and three antennas at the receive end.
But how does having multiple antennas help increase the throughput of the wireless link/network? More on that next time.