localization , communication using beam forming

7/31/2019 Localization , Communication Using Beam Forming

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SENSOR NETWORK-source localization andcommunication using beam forming and

SDMA

SUBMITTED BY,R.MANIGANDAN,

510811412009,

G.T.E.C


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Why WSN?

spatially distributed autonomous sensors

cooperatively pass their data through the network to a main location

characteristics of a WSN include:

I. power consumption constrains for nodes using batteries or

energy harvestingII. ability to cope with node failures

III. mobility of nodes

IV. communication failures

V. heterogeneity of nodes

VI. scalability to large scale of deployment

VII. ability to withstand harsh environmental conditions

VIII. ease of use


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BEAMFORMING


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BEAMFORMING

signal processing technique direct the majority of signal energy you transmit from a group of

transducers in a chosen angular direction.

used to control the directionality of the reception or transmission of a

signal on a transducer array.

used in sensor arrays for directional signal transmission or reception.

combining elements in a phased array in such a way that signals at

particular angles

achieve spatial selectivity.


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SDMA(space division multiple access)


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Space Division Multiple Access

Satellite communications mode

minimizes system cost.

In SDMA, also known as SDM (spatial-division multiplex), The antennas

are highly directional, allowing duplicate frequencies to be used for

multiple surface zones. Channel access method.

Offer superior performance in radio multiple access communication

systems.

By using smart antenna technology and differing spatial locations of

mobile units within the cell.

This is often done using phased array techniques.


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OBJECTIVE

establish OTH links using wireless sensor networks by each to act as asmart antenna array.

WSN is a uniformly distributed random array of sensor nodes.

non-cooperative source localization within the constraints of a WSN.

least squares estimator for DOA-based localization.

passive source localization scheme which exploits the NLOS signals

from non-cooperative sources.

DOA/TDOA-based scheme which uses localization through triangulation.

The TDOA information is used to discriminate between the LOS and the

NLOS signals


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WSN IN TACTICAL OPERATION


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OTH: over the horizon


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OTH : over the horizon

Over The Horizon (OTH) network by forming a multi-hop communication

link using the individual WSNs.

extended network made up of nodes of a larger Over The Horizon (OTH)

network is formed.

Once the OTH network is connected, the individual WSNs become part ofa larger network that can relay sensed data to an end user.


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SOURCE LOCALIZATION

WSN of locating a signal source by extracting the information in the

received signal.

Two primary approaches to source localization have evolved:

Direction of arrival (DOA) based techniques

Time difference of arrival (TDOA) based techniques least squares error estimator for DOA localization

passive source localization for non-line-of-sight (NLOS) signals.

DOA/TDOA source localization:

DOA estimator,

association algorithm for the identified signal bearings

source localization scheme


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SOURCE LOCALIZATION


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SOURCE LOCALIZATION

Space Division Multiple Access (SDMA)-based receiver is used for DOAestimation.

TDOA information is used between the line-of-sight (LOS) and the NLOSsignals and to associate the incoming multipath signal with thecorresponding source and reflector pair.

A technique is also provided to estimate the position and the orientationof the reflectors when site-specific database information is not available.

The proposed localization scheme allows a wireless sensor network to

perform single array localization

perform the localization in a distributed fashion

obtain source location estimates with NLOS signals

improve the location estimates compared with those obtainedusing the LOS information only


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BEAM FORMING


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Search for other wireless sensor

network

Beam forming with arrays of placed sensor

nodes

Geometric arrays(periodic-uniform)

Random arrays


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Array element distribution


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Linear array beam forming


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Planar array beam forming


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Beam forming array formation in

wireless sensor network

Linear array formation

Planar array formation


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Search method

Beam steering

Look-wait-rotate beam


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Phased array-simulation


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THANK YOU

localization , communication using beam forming

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