MIMO (Multiple Input Multiple Output)

[seminar class]

presented by:
Kumail.Khurram
Sagar Bele

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MIMO(Multiple Input Multiple Output) Technology
MIMO (multiple input, multiple output) is an antenna technology for wireless communications
in which multiple antennas are used at both the source (transmitter) and the destination
(receiver). The antennas at each end of the communications circuit are combined to minimize
errors and optimize data speed. MIMO is one of several forms of smart antenna technology, the
others being MISO (multiple input, single output) and SIMO (single input, multiple output).
In conventional wireless communications, a single antenna is used at the source, and another
single antenna is used at the destination. In some cases, this gives rise to problems with multipath
effects. When an electromagnetic field (EM field) is met with obstructions such as hills, canyons,
buildings, and utility wires, the wavefronts are scattered, and thus they take many paths to reach
the destination. The late arrival of scattered portions of the signal causes problems such as
fading, cut-out (cliff effect), and intermittent reception (picket fencing).In digital
communications systems such as wireless Internet, it can cause a reduction in data speed and an
increase in the number of errors. The use of two or more antennas, along with the transmission of
multiple signals (one for each antenna) at the source and the destination, eliminates the trouble
caused by multipath wave propagation, and can even take advantage of this effect. MIMO
technology has aroused interest because of its possible applications in digital television (DTV),
wireless local area networks (WLANs), metropolitan area networks (MANs), and mobile
communications