30-12-2009, 07:33 PM
MIMO means Multiple Input Multiple Output wireless communication systems.Recently, systems that use multiple antennas at the transmitter and the receiver were developed. Such systems are known as multiple input multiple output (MIMO) systems. The advantages are
budget / spatial diversity improvement and throughput improvement
from spatial multiplexing.
Spatial diversity: the fact that the probability of having
all antennas at bad locations is lowered as the number of
antennas increases.
Keywords Link budget improvement:
the signals from the various antennas can be combined
signal stronger than any of the individual signals.
spatial multiplexing : A way to exploit rich spatial dimensionality : signals received at different antennas are combinations of the
transmitted data streams.DSP algorithms can be used to recover the original data streams [3].
Spatial multiplexing can be either open-loop or
closed-loop. In open-loop , different streams are
simply transmitted from different antennas.
In closed-loop spatial every stream is transmitted from all of the antennas
using weights computed from the channel estimation.
spatial multiplexingimproves peak data rates and
increases spectrum efficiency.
HARDWARE REQUIREMENTS
multiple RF and baseband chains are required. The block daigram consists of
FEC block ,StreamSplit block ,a Spatial Mapping block, iFFTs and different antennas.
Shortcomings
-Higher power consumption.
- thermal and
battery life constraints limit tolerable power consumption
- tolerable cost impacted by market factor
Full seminar report:
[attachment=907]
budget / spatial diversity improvement and throughput improvement
from spatial multiplexing.
Spatial diversity: the fact that the probability of having
all antennas at bad locations is lowered as the number of
antennas increases.
Keywords Link budget improvement:
the signals from the various antennas can be combined
signal stronger than any of the individual signals.
spatial multiplexing : A way to exploit rich spatial dimensionality : signals received at different antennas are combinations of the
transmitted data streams.DSP algorithms can be used to recover the original data streams [3].
Spatial multiplexing can be either open-loop or
closed-loop. In open-loop , different streams are
simply transmitted from different antennas.
In closed-loop spatial every stream is transmitted from all of the antennas
using weights computed from the channel estimation.
spatial multiplexingimproves peak data rates and
increases spectrum efficiency.
HARDWARE REQUIREMENTS
multiple RF and baseband chains are required. The block daigram consists of
FEC block ,StreamSplit block ,a Spatial Mapping block, iFFTs and different antennas.
Shortcomings
-Higher power consumption.
- thermal and
battery life constraints limit tolerable power consumption
- tolerable cost impacted by market factor
Full seminar report:
[attachment=907]
