SMART ANTENNA 1. HUMAN HEARING SYSTEM – AN ANALOGY FOR SMART ANTENNA 2.
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Transcript of SMART ANTENNA 1. HUMAN HEARING SYSTEM – AN ANALOGY FOR SMART ANTENNA 2.
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SMART ANTENNA
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HUMAN HEARING SYSTEM – AN ANALOGY FOR SMART ANTENNA
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DEFINITION
A smart antenna system combines multiple antenna
elements with a signal processing capability to
optimize its radiation and/or reception pattern
automatically in response to the signal environment.
Beam the radio signal directly at a user to follow the
user as they move.
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SDMA
Space Division Multiple Access implies that more than
one user can be allocated to the same physical
communications channel simultaneously in the same
cell, provided they are separated by an angle.
In systems providing full SDMA, there will be much
more intracell handovers and therefore more
monitoring by the network is necessary.
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WHY SMART ANTENNA..?MULTI-PATH
PROPAGATION
Fading Different delays Inter Symbol Interference
To reject or stimulate multipath components by changing the radiation patterns
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CO-CHANNEL INTERFERENCE
Interference from other directions than wanted user
Increased noise level
To suppress unwanted user by placing nulls in directions of unwanted signals
To improve transmission quality and system capacity
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TYPES OF SMART ANTENNA
Switched lobe or switched beam:
Simplest technique Basic switching function between
separate directive antennas or predefined beams of an array
The setting that gives the best performance, usually in terms of received power, is chosen
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Dynamically phased array:
Generalization of the switched lobe concept Includes a direction of arrival (DoA) algorithm for the
signal received from the user Continuous tracking can be achieved
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Adaptive array:
DoA to determine the direction towards interferers is added
Radiation pattern can then be adjusted to null out the interferers
Maximize the signal to interference ratio by special algorithms & space diversity techniques (receive multipath signals & combine)
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How can an antenna be made more intelligent..?
I. Modifying the physical design by adding more elements
II. Antenna system can shift the signals before transmission at each of the successive elements for a composite effect
Controlling signal phasesA DSP weighting scheme
This basic hardware and software concept is known as the ‘phased array antenna’
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MIMO(MULTIPLE INPUT MULTIPLE OUTPUT)It’s the use of multiple antennas at both the
transmitter and receiver to improve communication performance.
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ADVANTAGESIncreased signal gain
Better range/coverage
Fewer base stations are needed which in turn reduces infrastructure cost
Interference rejection & load balancing
Increased capacitySpatial diversity
Multipath resolution
Higher data rates
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Legacy RF System
Power Distribution
Power Amplifier ModulePower Level
128W
Signal Interference from other users
Low Capacity
High Complexity
Conventional
PatentedSmart Antenna
Software
Power Distribution
Power AmplifierPower Level
2 W
High Capacity
Signal Interference from other users
Low Complexity
SmartAntenna
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APPLICATIONS
Applications Description
RADAR Phased array RADAR; air traffic control; synthetic aperture RADAR
SONAR Source location and classification
Communications Smart antenna systems; Directional transmission and reception; sector broadcast in satellite
communicationsImaging Ultrasonic; optical; tomographic
Geophysical Exploration
Earth crust mapping; oil exploration
Astrophysical Exploration
High resolution imaging of universe
Biomedical Neuronal spike discrimination; fetal heart monitoring; tissue hyperthermia; hearing aids
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