This presentation was made by NITMAS students of 2008-12 Batch Group-6...

1. GROUP - 6

2. Group members
Name Roll No
Subhabrata Biswas 18
Sourish Mukherjee 28
Souptik Roy 38
Ankit Pandey 55
Avishek Paul 56
Soumyajit Mazumdar 23

3. Contents
 Smart antenna array
 Why smart antenna array
 Elements of a smart antenna
 Types of smart antenna
 Switched Lobe
 Dynamically phased array
 Adaptive array
 Application
 Advantage &Disadvantage
 Conclusion
 Reference

4. Smart Antenna Array:
Antenna array with a digital signal processing
capability to transmit and receive in an adaptive and spatially
sensitive manner.

5. Why Smart Antenna
 Higher Capacity
 Higher Coverage
 Higher bit rate
 Improved link quality
 Spectral efficiency
 Mobility

6. Elements of a Smart Antenna
 Number of radiating elements
 A combining/dividing network
 Control unit

7. Types of Smart Antennas
 Switched lobe (SL)
 Dynamically phased array (PA) antenna
 Adaptive antenna array

8. Basic Working Mechanism

9. Beam-forming
 Technique in which the gain
pattern of an adaptive array is
steered to a desired direction
through either beam steering or
null steering signal processing
algorithms
 Adaptive beam forming algorithms
can provide substantial gains (of Antenna Pattern of 7-element
the order of 10log(M) dB, where M uniform equally spaced
is number of array elements) circular array.

10. Adaptive Beam-forming
An adaptive beam former is a
device that is able to separate
signals co-located in the
frequency band but separated in
the spatial domain. This provides
a means for separating the desired
signal from interfering signals.
A two element adaptive array for
interference suppression

11. Switched beam
 Consists of a set of predefined beams.
 Allows selection of signal from desired user.
 Beams have narrow main lobe & small side lobes.
 Signals received from side lobes can be significantly attenuated.
 Uses a linear RF network called Fixed Beam-forming network that
combines M antenna elements to form up-to M directional beams.

12. Why we need to form
all the beams ?

13. Dynamically phased array :
Consists of either a number of fixed beams with one beam turned
on towards the desired signal or a single beam (formed by
phase adjustment only) that is steered toward the desired
signal.

14. Dynamically phased array :
 A Direction of arrival algorithm(DoA) tracks the user’s
signal as he roams within the range of that beam that is
tracking him
 Generalization of switched beam concept where received
power is maximized.
 More efficient than Switched beam system

15. What is DoA?
The goal of direction-of-arrival (DoA) estimation is to use the
data received on the downlink at the base-station sensor array
to estimate the directions of the signals from the desired mobile
users as well as the directions of interference signals.

16. Types of
Dynamically phased array
 Time domain beamformers:
Delays the incoming signal from each array element by a certain
amount of time & then adds them.
 Frequency domain beamformers:
Different frequencies are separated. Applying different sum & delay
to each frequency it is possible to point out the main lobe.

17. Comparison between
Switched lobe & Phased array

18. Comparison between
Switched lobe & Phased array

19. Adaptive Array
Reducing output noise and
enhancing the detection of
desired signals.
Array of antenna element.
Real-time adaptive receiver-
processor

20. Types of Adaptive Array
Processing
 TDMA addaptive array processing
 CDMA addaptive array processing

21. TDMA Adaptive Array
Processing
 Reverse link configuration for a TDMA system
 Forward link configuration for a TDMA system

22. CDMA Adaptive Array
Processing
Reverse link configuration for a CDMA system.
Forward link configuration for a CDMA system.

23. Comparison between
Switched lobe, Phased array &
Adaptive Array

24. Application
 Mobile Communication
GSM
CDMA
 Wireless Communication
 Aerospace Application.
 IS-136
 SDMA
 EDGE

25. Mobile Communication
 Improved services.
 Advanced mobile phone system(AMPS).
 Advanced TDMA.
 User friendly services.

26. GSM
(Global system for Mobile Communication)
 Mainly used in the base station.
 Full beam adaptation in uplink & downlink.
 Bit rate of 1%
 Carrier interference of -14 db.

27. CDMA
Features
 Diversity Cellular Antennas with 800/1900 MHz
bands
 High accuracy GPS receiver
 Supports UART and/or USB interfaces
Benefits
 Designed for easy internal integration
 no need of SIM card
 Provides integrators with a network pre-approved
communication device
 Fleet Management and diagnostics
 In-dash Internet access
 General Automotive Aftermarket

28. Wireless Communication
 Over come the limitations of omni-directional antenna.
 Secterized antenna and coverage pattern.

29. Aerospace Application
 Smart antenna adapts the electromagnetic condition.
 Increase of antenna gain
 Airborne satellite communication.
 Reliable source of communication.

30. SDMA
 Spatial Division Multiple Access
Uses an array of antennas to
provide control of space
 Network planning (frequency) is
simpler
 More network management
upgrade required

31. IS-136
 TDMA with 3 users per channel
 162 symbols/slot
 14 symbol synchronization sequence
 Two receive antennas at base

32. Smart antennas in generation 3 rd
systems: EDGE
 High data rate ( 384 kbps) service based on GSM, for
both Europe and North America
 BPSK at 270.833 kbps
 26 symbol training sequence
3 58 26 58 3 8.25
576.92 s

33. Advantages of smart antenna
 Both phased and adaptive arrays provide increased power by
providing higher gain for the desired signal.
 In terms of interference suppression, phased arrays reduce the
probability of interference with the narrower beam, and adaptive
arrays adjust the beam pattern to suppress interference.

34. Conclusion
 The use of smart antennas is not purely a radio transmission
issue.
 It also influences network services such as handover and
connection setup.
 A smart antenna is a digital wireless communications
antenna system that takes advantage of diversity effect at the
source (transmitter), the destination (receiver), or both.

35. Reference
 G. K. Chan, “Effects of Sectorization the Spectrum
Efficiency of Cellular Radio systems,” Transaction on
Vehicular Technology, pp.217-225, vol.41, no.3, Aug 1992.
 M. G. Jansen, R. Prasad, “Capacity, Throughput, and
Delay Analysis of a Cellular DS CDMA System with Imperfect
Power Control and Imperfect Sectorization,” Transaction on
Vehicular Technology, pp.67-75, vol.44, no.1, Feb 1995.
 X. Yang, S. Ghaheriand N. R. Tafazolli, “Sectorization
Gain in CDMA Cellular Systems,” First Conference on 3G
Mobile Communication Technologies, pp.70-75, 2000.