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Adaptive Usage of Main Resources in MIMO-Cognitive Radio Networks Shalva Kvirkvelia (PHD student) Prof. Teimuraz Kortua Prof. Jemal Beridze
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GEORGIA
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Tbilisi
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Georgian Technical University Department of Telecommunication
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MIMO system
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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.
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Cognitive radio
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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
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Cognitive-MIMO cognitive radio network data on the MIMO channel resources-adaptive algorithms optimal transmission circuit
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Multipath propagation
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Inter symbol interference
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Cyclic prefix
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Rate loss
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Resource loss
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Multipath estimating tool
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Example
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IEEE 802.16-2004 OFDM PHY link, Including Space-Time Block Coding
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Results
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Adaptive MIMO System with OSTBC
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Results
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Downlink Transport Channel (DL-SCH) Processing
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Results
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LTE Transmit Diversity Example
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Results
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Thank you Questions?
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