1. SMART ANTENNAS SMART ANTENNAS apoorva k. Shetti 2bu09ec006
PRESENTATION BY
apoorva k. Shetti
2bu09ec006
UNDER THE GUIDANCE OF
Lect. AMARJEETSINGH THAKUR
PRESENTED BY
Mr. apoorva k. Shetti

2. CONTENTS INTRODUCTION TYPES OF SMART ANTENNAS
COMPARISION BETWEEN SWITCHED BEAM AND ADAPTIVE ARRAY
SDMA(SPACE DIVISION MULTIPLE ACCESS)
ADVANTAGES AND DISADVANTAGES
APPLICATION
CONCLUSION
REFERENCES

3. INTRODUCTION
Antenna is electrical device which converts electric power into electromagnetic waves or vice versa.
Omni directional and directional antennas.
Multipath and Co channel Interference.
Figure A:Omni directional antenna B. Directional antenna
coverage pattern coverage pattern

4. Figure : Smart antenna analogy with human
What is SMART ANTENNA ?
A smart antenna consists of an antenna array, that changes the array pattern in response to signal environment to improve the performance of a communication system.
Figure : Smart antenna analogy with human

5. THE AIM OF SMART ANTENNA SYSTEM
To maximize the antenna gain in the desired direction.
To minimize the gain in directions of interferers.

6. TYPES OF SMART ANTENNA
SWITCHED BEAM ANTENNA
- a finite number of fixed ,predefined patterns.
ADAPTIVE ARRAY ANTENNA
- an infinite number of patterns (scenario based) that are adjusted in real time.

7. SWITCHED BEAM ANTENNAS
This systems form multiple fixed beams with heightened sensitivity in particular directions.
When incoming signal detected it determines the beam which is best aligned based on SOI and switches to that beam to communicate with user.
As the mobile unit moves throughout the cell, the switched-beam system detects the signal strength and continually switches the beams as necessary.

8. Figure- Switched Beam System Coverage Patterns (Sectors)
Contd…
Figure- Switched Beam System Coverage Patterns (Sectors)
It subdivides sector into many narrow beams, then each beam is
considered as individual sector serving user or group of users.

9. Figure : Block diagram of Switched beam systems
Contd...
Figure : Block diagram of Switched beam systems
PSN, which forms multiple beams looking in certain directions.
RF Switch actuates the right beam in the desired direction.

10. Contd…
The selection of right beam is made by control logic which is governed by an algorithm.
The algorithm which scans all the beams and selects the one strongest receiving signal based on a measurement made by the detector.
The overall goal of the switched-beam system is to increase the gain according to the location of the user.

11. ADAPTIVE ARRAY ANTENNAS
Systems are really smart because they are able to dynamically react to the changing RF environment with its infinite scenario based patterns.
They can direct the main beam toward the SOI(Signal Of Interest) while suppressing the antenna pattern in the direction of the interferers.
It can customize an appropriate radiation pattern for each individual user.
Dynamically adjust the antenna pattern to enhance reception while minimizing or fully rejecting interference .

12. Figure- Adaptive Array System Coverage Pattern
Contd…
Figure- Adaptive Array System Coverage Pattern
This provides optimal gain while simultaneously identifying, tracking, and minimizing interfering signals.

13. Figure : Block diagram of Adaptive array systems
Contd…
Figure : Block diagram of Adaptive array systems
D/C : Converts from RF to IF.
ADC : Converts Analog to Digital for further processing.
W’s : It contains amplification and phase information

14. SPACE DIVISION MULTIPLE ACCESS
Among the most sophisticated utilization of smart antenna technology.
It employs advanced technique to, in effect, locate and track fixed and mobile terminals, adaptively steering transmission signal toward user and interferers.
Beams are sliced to keep different users in different beams at the same frequency which allows reuse of frequency.
This technology achieves superior levels of interference suppression and reduces RF pollution.

15. Contd…
Figure: SDMA technology(general and actual mechanism)
This is the next step in an evolutionary path towards increasing
the capacity of cellular systems

16. COMPARISION OF SWITCHED BEAM ANTENNA AND ADAPTIVE ARRAYS
CRITERIA
SWITCHED BEAM
ADAPTIVE ARRAYS
INTEGERATION
Easy to implement
Low cost
Transceiver complexity
High cost
RANGE/COVERAGE
More coverage
compared to
conventional systems
Less coverage compared
to adaptive array
compared to switched
beam system
INTERFERENCE REJECTION
Difficulty in
distinguishing
between desired signal
and interferer
Does not react to the
movement of
Interferers.
Focusing is narrower
Capable of nulling
interfering signals

17. ADVANTAGES OF SMART ANTENNA
Enhance coverage through Range extension.
Fully controllable by software so less manual operations.
Reduction in transmitted power.
Reduce co-channel interference (CCI) and multipath interference.
Provides high security.
Improve system capacity.
Compatibility, it can be applied to various multiple access techniques such as TDMA,FDMA ,and CDMA.

18. Smart Antenna’s Drawbacks
Their transceivers are much more complex than traditional base station transceivers.
Expensive.

19. APPLICATION Cellular and wireless networks
Electronic warfare (EWF) as a countermeasure to electronic jamming
Satellite systems

20. CONCLUSION
Smart antennas are the intelligent antenna systems that vastly improve the efficiency of wireless transmission.
SAS can achieve high transmission data rate and coverage area by effectively reducing multipath and co channel interference.
Smart antenna systems are software-controllable, remotely configurable.
Promising technology to resolve the traffic capacity .

21. References
[1].R. H .Roy, “An overview of smart antenna technology and its application on wireless communication systems,” Proc .IEEE conf.personal wireless comm.,2007, pp. 234 – 238 [2].Chryssomallis, M., Smart antennas , IEEE Antennas and Propogation Magazine, 42(3): [3].S. F. Shaukat , Mukhtar ul Hassan, R. Farooq, H. U. Saeed and Z. Saleem, “Sequential studies of beam forming algorithms for smart antenna systems”, world applied sciences journal , vol .6, no. 6, pp ,2009 [4]. [5].