MIMO antenna from FORSIS

Startseite » Service » Service Knowledge » antenna technology
Staplerterminal Resistiv WLAN IP65 Min

MIMO antenna according to IEEE802.11n standard

The new standard IEEE 802.11n was approved on September 12, 2009. FORSIS GmbH uses this WLAN standard specifically for the mobile FORSIS MOBILE series. The FORSIS variant implements the n standard and is at the same time robust and designed according to protection class IP65.

When realizing the antenna according to IEEE802.11n, the aim was clearly the special design in the direction of the so-called MIMO (Multiple-Input-Multiple-Output) data transmission method.

MIMO systems offer higher data transmission rates, longer ranges and are not only "immune" to multipath propagation, they actually exploit it. A MIMO system is therefore particularly suitable for use in industrial indoor areas, without a direct line of sight between a PC and a router, most suitable.

The antenna was implemented as a MIMO antenna system consisting of three separate dual-band antennas. All individual antennas are placed on a printed circuit board and manufactured using a chemical manufacturing process. The entire antenna is housed in a robust polycarbonate ABS (PC-ABS) housing. The complete antenna should be easy to mount on a given PC case and allow easy connection of coaxial cables.

Thus, the optimal illumination of the environment is achieved in order to support the advantages of the greater range and higher data transmission rate in the best possible way.

The following standards should be supported:

  • IEEE 802.11a
  • IEEE 802.11b
  • IEEE 802.11g
  • IEEE 802.11n

WLANs based on the new IEEE standard 802.11n promise drastically higher throughput rates of up to 600 Mbit/s. A minimum data rate of 100 Mbit/s is guaranteed. The throughput does not depend solely on the clock rate of the interface, but is also significantly influenced by additional protocol overhead and retransmissions that can be traced back to poor signal quality. These rates are achieved through even more complex technology than previous wireless LANs and the interaction of a large number of different functions.

802.11n achieves the maximum data rate of up to 600 Mbit/s through new modulation processes and the (optional) use of a 40 megahertz wide transmission channel. Furthermore, two to a maximum of four antennas are used. The latter makes it possible to spatially use a radio channel in the same frequency range several times and thus to guarantee parallel data transmission. This not only increases the speed, but also the range. This mechanism is called "Multiple Input, Multiple Output" (MIMO).

MIMO is one of the innovations in wireless data transmission. The term multipath describes the phenomenon of the different propagation paths of a radio signal, caused by reflections on walls, furniture and people. The transmitted signal arrives at the receiver several times, with a time delay and with different signal strengths; there the received signals are superimposed and appear as a blurring of the transmitted signal. The 802.11a/b/g standards attempt to filter out the effects of multipath transmission by having the receiver only evaluate the strongest signal. The MIMO technology specified in 802.11n is now using the transmission of signals over multiple paths for WLAN transmission for the first time, thereby achieving multiple simultaneous data transmissions.

If several antennas are used (at a distance of half a wavelength of the carrier frequency), the receiver receives additional information about the direction of arrival of the radio waves. Although the signals operate on the same radio channel, this allows the spatial signature of two signals to be distinguished from one another. This increases the channel capacity. If the transmission signal is emitted by two (or more) antennas, a directional effect can be achieved at the antennas through a time delay. This process is called beamforming. If one targets several receivers using beamforming, one speaks of spatial multiplex gain (spatial multiplexing).


"Wir beantworten gerne Ihre Fragen."

+49 (0) 751 76 414 360