In LTE wireless networks, MIMO antenna technology is used. MIMO stands for Multiple Input / Multiple Output.
Instead of a sending and receiving antenna, in the MIMO technology, up to four transmitter antennas and four receiver antennas to be used. The corresponding codes are 4×4 four transmitting and receiving antennas, or 2×2 for two transmitting and receiving antennas. MIMO enables simultaneous transmitting multiple data streams on the same frequency. Systems with a single antenna are called SISO (Single Input / Single Output).
In principle, the multiple-antenna systems have the following advantages: First, you get a bigger reception power and thus greater range, secondly suppress interference from other radio waves better, make for a better connection quality thirdly and fourthly, for better transfer rates. However, one cannot utilize all four at the same time maximum benefits: You have to decide whether you want to improve the system in a data-transfer speed or the range or quality of the connection.
Key technology for LTE
MIMO is a key technology in LTE wireless networks, since they are the spectral efficiency is improved. However, MIMO is not only used on LTE, but also used in WiMAX and WLAN systems. By using multiple antennas, in LTE, the reception signal improved and interference can be reduced – that is, it results in less interference from other radio frequency used. But the most important: The MIMO technology is at the LTE transmission of the data stream to be distributed to up to four transmit and receive antennas. This increases the amount of data that is transferred per unit time, thus ensures a higher transmission speed – while reducing the error rate.
LTE can use up to four times four antennas, it provides for the 3GPP Release 8, which is defined in the technical specifications for LTE. Also two times two MIMO systems are possible. In a 2×2 MIMO, the data rate in comparison to a system can be doubled with a respective antenna almost.
Devices with MIMO antennas
A technical challenge may be the equipment of devices with multiple antennas – a smartphone offers relatively little room for a higher number of antennas. At low frequencies such as the 800-megahertz band, the problem is compounded by the fact that there are larger antennas needed. Especially in the countryside, however, LTE will use this frequency range. Installation of multiple antennas in laptops is problematic. Since the LTE stations will initially replace the missing country’s DSL, it imposes the use of MIMO technology is quite well possible.