Adaptive Usage of Main Resources
in MIMO-Cognitive Radio Networks
Shalva Kvirkvelia (PHD student)
Prof. Teimuraz Kortua
Prof. Jemal Beridze
GEORGIA
Tbilisi
Georgian Technical University
Department of Telecommunication
MIMO system
Linear Capacity Growth
Theoretical The MIMO Systems capacity grows
linearly with the number of antennas. 2x2
MIMO doubles the capacity and 4x4 MIMO
quadruples capacity.
The linearity occurs only when we have ideal
channel conditions, there is no interference
among subcarriers, channels are orthogonal
and there is no correlation between the
channels.
Cognitive radio
The four major functions of a cognitive
network are
• Spectrum sensing: detection of unused frequency
ranges
• Spectrum management: selection of the unused
frequency range that best fulfills the
requirements
• Spectrum mobility: possibility to switch
frequencies without data loss and additional
delay (e.g. by detecting a band with less
interference)
• Spectrum sharing: intelligent, multiple access to a
spectrum within a network
Cognitive-MIMO
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cognitive radio network
data on the MIMO channel
resources-adaptive algorithms
optimal transmission circuit
Multipath propagation
Inter symbol interference
Cyclic prefix
Rate loss
Resource loss
Multipath estimating tool
Example
IEEE 802.16-2004 OFDM PHY link,
Including Space-Time Block Coding
Results
Adaptive MIMO System with OSTBC
Results
Downlink Transport Channel (DL-SCH)
Processing
Results
LTE Transmit Diversity Example
Results
Thank you
Questions?