The technical characteristics of the WI-FI on different devices can be seen in the description of the presence of modules WI-FI 2x2, and some manufacturers stipulate that the presence of 2 antennas will increase the speed twice as eg when using the 802.11n standard to receive the data transmission rate up to 300Mbps / sec.
Although this interpretation is not quite right, just the device has two WI-FI module working together, one module on one channel, the second module on the other channel.
Software two streams of information are combined into one, and this is achieved to increase the transmission speed.
But to complete the work, both devices operating in the network WI-FI should maintain configuration 2x2.
Description and availability of the two antennas is presented to users for the sake of clarity, there are 2 device antenna means working twice as fast, but the antennae can put 10, but with only one module WI-FI they are completely useless.