20919573 ppt for design and analysis of triple band aperture coupled micro strip antenna

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G.ANKITHA -G.ANKITHA -03251A170303251A1703 M.ANUSHA -M.ANUSHA -03251A170603251A1706 K.DIVYA -K.DIVYA -03251A171503251A1715 OUR EXTERNAL GUIDE:OUR EXTERNAL GUIDE:

MRS.ADI LAKSHMIMRS.ADI LAKSHMI

OUR INTERNAL GUIDE:OUR INTERNAL GUIDE:

MRS.J.SUNITA KUMARIMRS.J.SUNITA KUMARI

PROJECT PROGESS REPORT PROJECT PROGESS REPORT BYBY

DESIGN AND ANALYSIS OF TRIPLE BAND APERTURE COUPLED MICROSTRIPANTENNA

CONTENTS

• Overview• Radiation Mechanism• Feeding Techniques• Selection Of Substrate• Design Of Single Patch Antenna• Structure Of Triple Band Microstrip Antenna• Design Procedure• Conclusion

OVERVIEW OF MICROSTRIP OVERVIEW OF MICROSTRIP ANTENNAANTENNA

• consists of a radiating patch on one side of a dielectric substrate which has a ground plane on the other side

• The patch is generally made of conducting material such as copper or gold.

DIFFERENT SHAPES OF THE PATCHES

Square Rectangle Dipole Circle

TraingleElliptical

Circular ring

RADIATION MECHANISM

• Radiates because of electric fringing fields between the edges of the conductor element and the ground-plane behind it.

• Can be represented by two slots λ/2 apart.

FEEDING METHODS

• Microstrip line feed

• Coaxial probe feed

• Proximity coupling

• Aperture coupling

MICROSTRIP LINE FEED

COAXIAL PROBE FEED

PROXIMITY COUPLING

APERTURE COUPLING

COMPARISON OF FEEDING TECHNIQUES

SELECTION OF SUBSTRATE

• The substrate plays a double role: electrically, it is an integral part of the transmission line circuits and antennas; mechanically, it is the support of the structure.

• The electrical properties are the relative permittivity ξ, the substrate thickness ‘h’ and the dielectric loss factor tanδ.

DESIRABLE CHARACTERISTICS OF THE SUBSTRATE

• Thick substrates with low dielectric constant.

¤ better efficiency ¤ larger bandwidth ¤ loosely bound fields for radiation into

space. • In the present design RT/Duroid 5880 is

taken as the dielectric that accounts for high efficiency and lightweight of the antenna.

Characteristics of RT/Duroid

Parameter Characteristics of RT/Duroid Uniform dielectric constant Less than ±1% from 10^6 through 10^10 Hz Low dissipation

factor RT/Duroid has a very low dissipation factor. It is superior to allother strip line composite materials.

Dimensional stability

Withstands temperatures up to 550ºF

Close thickness Control

Tolerance of ±3% on overall laminate thickness

Excellent bond strength

Excellent adhesion is maintained even after soldering, plating and exposure to elevated temperatures.

Environmental stability

Extremely low water absorption.They are inert at room temperatures to high humidity and atmospheric pollutants such as industrial gases and marine salts.

DESIGN OF TRIPLE BAND APERTURE- -COUPLED MICROSTRIP ANTENNA

layer3

layer2

layer1

groundlayer

Groundlayer with a microstrip feed line

Layer1 with coupling slots

Layer2 with coupling slots on the patch

Layer3 with patches on it

BASIC STRUCTURE OF TRIPLE BAND ANTENNA

DESIGN PROCEDURE

A. Design procedureprocedure for layer 2

a Width

b Effective dielectric constant

c. Extension of length

d. Actual length

5mm

0.5mm

Coupling slots on patch of layer 2

7mm

84mm

84mm47mm 7mm

47mm

0.7mm 0.5mm

5mm

B. Design procedure for the patches on layer3: B. Design procedure for the patches on layer3:

a. Effective dielectric constant

In which

b. Actual length of the patch

where

c. Slot dimensions are84mm

84mm

Patches on Layer 3

20mm

f.Calculation of microstrip line width:

84mm

84mm

72mm

5mm

VSWR MEASUREMENT

1.Selection of sweep frequency range.

2.Selection of port.

3.Calibration of the VNA.

4.Connecting the antenna and observing the trace.

DESIGN MASTER DRAWING ARTWORK LAYOUT

PHOTO REDUCTIONPOSITIVE DEVELOPMENT

LAMINATE CLEANING RESIST APPLICATION

RESIST EXPOSURERESIST DEVELOPMENT

INSPECTION STRIPPING ASSEMBLY

ETCHING

FABRICATION PROCESS

PHOTOLITHOGRAPHIC PROCESS

CLEANING

DEPOSITION OF PHOTORESISTIVE LAYER

RESIST EXPOSURE

RESIST DEVELOPMENT

INSPECTION

ETCHING

STRIPPING

PLOT OF VSWR

RETURN LOSS MEASUREMENT

o Return Loss = 20log| ρ |o

RETURN LOSS PLOT

RADIATION PATTREN

o

MEASUREMENT OF RADIATION PATTERN

o AUT is mounted on the antenna positioner.o Signal source is connected to standard horn.o Signal of desired frequency is transmitted.o Pattern is recorded by rotating the antenna through 360º.

Setup For Radiation Pattern Measurement

o Beam width : The half power beamwidth is equal to the angular width between directions where the radiated field decreases by 3dB.

o Beam width is calculated from the measured radiated pattern.

RADIATION PATTERN AT 2.4GHz

Beam Width :Horizontal Plane – 66.6ºVertical Plane – 117.9º

RADIATION PATTERN AT 4.1GHz

Beam Width :Horizontal Plane – 34.2ºVertical Plane – 122.4º

RADIATION PATTERN AT 5.16GHz

Beam Width :Horizontal Plane – 26.1ºVertical Plane – 82.8º

GAIN MEASUREMENT

o Standard comparison method is used.

PROCEDURE:

o Radiation pattern of the test antenna and standard antenna are measured with the same transmitting antennao The difference between the power levels is calculated.o The difference added with the actual gain of the standard antenna gives the gain.

Freq. in GHz

A.U.T Pr(dB)

STD HORN PrH(dB)

Difference Pr Level PrA ± PrH

Gain STD HORN (dB)

Gain A.U.T (dBi)

Remarks

Std.AntModal No

FREQ. RANGE

2.4 -30.5 -16.88 -13.615 16.85 3.235 12-1.7 12-3.95  

1.7to 2.60

4.11 -35.12 -21.86 -13.26 17.4 4.14 3.95to5.85

5.16 -36.16 -23.6 -12.56 18.85 6.29

MEASURED GAIN

CONCLUSION

QUERIES ??

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