project report4

8/10/2019 Project Report4

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CHAPTER 1

1.1 Introduction

Microstrip antennas are low profile, conformable to planar and non planar surfaces, simple andinexpensive to manufacture on printed circuited technology, mechanically robust when mounted

on rigid surfaces, compatible with MMIC designs. They are also referred to as patch antennas.

These antennas are very versatile in terms of resonant frequency, polarization, pattern, and

impedance. In addition, by adding loads between the patch and the ground plane, such as pins

and varactor diodes, adaptive elements with variable frequency, impedance, polarization and

pattern can be designed.

The rectangular microstrip patch antenna is usually made of a conducting material. The

rectangular microstrip patch antenna is parallel to the ground plane. The rectangular microstrip

patch and the ground plane are separated by substrate. The basic configuration of the rectangularmicrostrip patch antenna is described in fig1.

Fig 1.1: Basic configuration of the rectangular microstrip patch antenna

However, there are certain disadvantages of microstrip antennas such as low efficiency, low

power, high Q (sometimes in excess of 100), poor polarization purity, poor san performance,

spurious feed radiation and very narrow frequency bandwidth, which is typically only a fraction

of a percent or at most a few percent.

There are certain methods to improve the efficiency of microstrip antennas such as increasing theheight of substrate which can extend the efficiency upto 90% and bandwidth upto 35%.In

addition, microstrip antennas also exhibit large electromagnetic signatures at certain frequencies

outside the operating band.


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1.2Characteristics of Microstrip patch antenna

a) Consists of very thin metallic strip- t


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The transmission line model is easiest of all, it gives good physical insight, but is less

accurate and it is more difficult to model coupling. Compared to transmission line model,

cavity model is accurate but at the same time more complex.

However, it also gives good physical insight and is rather difficult to model couplingalthough it has been used successfully. In general when applied properly, he full wave

models are very accurate, very versatile, and can treat single elements, finite and infinite

arrays, stacked elements, arbitrary shaped elements, and coupling. However they are the most

complex methods and usually gives the less physical insight. We have done analysis using

transmission line model only. The patch configuration used in all the three designs is

rectangular.

1.5 Basic principle of operation

The metallic patch essentially creates a resonant cavity, where the patch is the top of thecavity, the ground plane is the bottom of the cavity, and the edges of the patch form the sides

of the cavity. The edges of the patch act approximately as an open-circuit boundary

condition. Hence, the patch acts approximately as a cavity with perfect electric conductor on

the top and bottom surfaces and a perfect magnetic conductor on the sides. This point of

view is very useful in analyzing the patch antenna, as well as in understanding its behavior.

Inside the patch cavity the electric field the electric field is essentially z directed and

independent of the z coordinate. Hence, the patch cavity modes are described by a double

index (m, n). For the (m, n) cavity mode of the rectangular patch the electric field has the

form

W

yn

L

xmAE mnZ

coscos

WhereL is the patch length and W is the patch width.

The patch is usually operated in the(1, 0) mode, so that L is the resonant dimension, and the

field is essentially constant in the y direction. The surface current on the bottom of the metal

patch is then x directed, and is given by For this mode the patch may be regarded as a wide

microstrip line of width W, having a resonant length L that is approximately one-half

wavelength in the dielectric. The current is maximum at the centre of the patch, x = L/2,while the electric field is maximum at the two radiating edges, x = 0 andx =L. The width

W is usually chosen to be larger than the length (W =1.5 L is typical) to maximize the

bandwidth, since the bandwidth is proportional to the width. (The width should be kept less

than twice the length, however, to avoid excitation of the (0,2) mode.)


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At first glance, it might appear that the microstrip antenna will not be an effective radiator

when the substrate is electrically thin, since the patch current in will be effectively shorted by

the close proximity to the ground plane. If the modal amplitude A10 were constant, the

strength of the radiated field would in fact be proportional to h. However, the Q of the cavity

increases as h decreases (the radiation Q is inversely proportional to h). Hence, the amplitude

A10 of the modal field at resonance is inversely proportional to h. Hence, the strength of the

radiated field from a resonant patch is essentially independent of h, if losses are ignored.

The resonant input resistance will likewise be nearly independent of h. This explains why a

patch antenna can be an effective radiator even for very thin substrates, although the

bandwidth will be small.

1.6 Software usedADS (Advanced design system) will be used to design and analyze the performance of

microstrip patch antenna. Advanced Design System is the leading electronic design automation

software for RF, microwave and signal integrity applications. ADS has been used in innovative

and commercially successful technologies, such as S-parameters and 3D EM simulators, used by

leading companies in the wireless communication and networking, and aerospace and defense

industries.

ADS provide full, standards-based design and verification with Wireless Libraries and circuit-

system-EM co-simulation in an integrated platform. ADS software is one of the strongest

software. It is based on FDTD (finite domain time difference method), FEM (finite element

method) and MM (moment method) methods. Moment method is also referred to as low

frequency asymptotic. The ADS platform comprises solutions for design entry, synthesis,

system, circuit, 3D EM simulation, analysis/post processing, and a complete flow to

manufacturing. It easily integrates with the designer's enterprise IC or PCB framework.


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CHAPTER 2

2.1

Fundamental Parameters of Antenna

2.1.1 Radiation Pattern

An antenna radiation pattern or antenna pattern is defined as a mathematical function or a

graphical representation of how the electric or magnetic field intensities vary with respect to the

angular positions, elevation and azimuth, for a fixed range. Radiation properties include power

flux density, radiation intensity, field strength, directivity, phase or polarization

Figure 2.1: Coordinate system for antenna analysis

2.1.2

BeamWidth

The beamwidth of an antenna is defined as the angular separation between two identical points

on opposite sides of the pattern maximum.. One of the most widely used beamwidth is the Half-

Power Beamwidth which is defined asIn a plane containing the direction of the maximum of a

beam, the angle between the two directions in which the radiation intensity is one-half value of

the beam

The angular separation between the first nulls of the pattern, and it is referred to as the First-Null

Beam width (FNBW).

Fig.2.2: Radiation lobes and beam widths of an antenna pattern


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2.1.3 Radiation Intensity

Radiation intensity in a given direction is defined as the power radiated from an antenna per unit

solid angle. The radiation intensity is a far-field parameter, and it can be obtained by multiplying

the radiation density by the square of the distance.

2.1.4 Directivity

The Directivity of an antenna is defined as the ratio of the radiation intensity in a given direction

from the antenna to the radiation intensity averaged over all directions. The average radiation

intensity is equal to the total power radiated by the antenna divided by 4.

A

D

4

2.1.5 Antenna Efficiency

Related with an antenna, there are a number of efficiencies. The total efficiency, takes into

account losses at the input terminals and with the structure of the antenna. Such losses may be

due to reflections because of the mismatch between the transmission line and the antenna

conduction and dielectric losses.

2.1.6

Antenna Gain

The gain of the antenna is closely related to the directivity, it is a measure that takes into account

the efficiency of the antenna as well as its directional capabilities. It is defined as the ratio of the

intensity, in a given direction, to the radiation intensity that would be obtained if the power

accepted by the antenna were radiated isotropically.

2

4

eAG


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2.2 Feeding Techniques

2.2.1 Inset Feed

This feed yields high input impedance. Since the current is low at the ends of a half-wave patch

and increases in magnitude toward the center, the input impedance could be reduced if the patch

is fed closer to the center. One method of doing this is by using an inset feed.

Fig. 2.3 Patch Antenna with an Inset Feed.

2.2.2. Coaxial Cable or Probe Feed

Microstrip antennas can also be fed from underneath via a probe as shown in Figure 2.4. The

outer conductor of the coaxial cable is connected to the ground plane, and the center conductor is

extended up to the patch antenna.

Fig2.4: Coaxial cable feed of patch antenna.

The coaxial feed introduces an inductance into the feed that may need to be taken into account if

the height hgets large (an appreciable fraction of a wavelength). In addition, the probe will also

radiate, which can lead to radiation in undesirable directions.


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2.2.3 Coupled (Indirect) Feeds

The feeds above can be altered such that they do not directly touch the antenna. For instance, the

probe feed in Figure 2.4 can be trimmed such that it does not extend all the way up to the

antenna. The inset feed can also be stopped just before the patch antenna, as shown in Figure 2.5

Fig2.5: Coupled (indirect) inset feed.

The advantage of the coupled feed is that it adds an extra degree of freedom to the design. The

gap introduces a capacitance into the feed that can cancel out the inductance added by the probe

feed.

2.2.4 Aperture Feeds

Another method of feeding microstrip antennas is the aperture feed. In this technique, the feed

circuitry (transmission line) is shielded from the antenna by a conducting plane with a hole

(aperture) to transmit energy to the antenna, as shown in Figure 2.6.

Fig2.6. Aperture coupled feed.


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The upper substrate can be made with a lower permittivity to produce loosely bound fringing

fields, yielding better radiation.

The lower substrate can be independently made with a high value of permittivity for tightly

coupled fields that don't produce spurious radiation. The disadvantage of this method is

increased difficulty in fabrication.

2.4Transmission line model

This model represents the microstrip antenna by two slots of width W and height h, separated by

a transmission line of length L. The microstrip is essentially a non-homogeneous line of two

dielectrics, typically the substrate and air.

Fig2.7. Microstrip line Fig2.8. Electric field lines

Hence, as seen from Figure , most of the electric field lines reside in the substrate and parts of

some lines in air. As a result, this transmission line cannot support pure transverse-electromagnetic (TEM) mode of transmission, since the phase velocities would be different in

the air and the substrate. Instead, the dominant mode of propagation would be the quasi-TEM

mode. Hence, an effective dielectric constant ( reff ) must be obtained in order to account for the

fringing and the wave propagation in the line.

The value of reff is slightly less than r because the fringing fields around the periphery of the

patch are not confined in the dielectric substrate but are also spread in the air as shown in Figure

above. The expression for reff is given by Balanis as:

21

1212

1

2

1

W

hrrreff

where reff = effective dielectric constant

r = dielectric constant of substrate

h = height of dielectric substrate

W = width of the patch


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Figure given below shows a rectangular microstrip patch antenna of length L, width W resting on

a substrate of height h. The co-ordinate axis is selected such that the length is along the x

direction, width is along they direction and the height is along thez direction.

Fig2.9. Microstrip patch antenna

In order to operate in the fundamental 10TM mode, the length of the patch must be slightly less

than /2 where is the wavelength in the dielectric medium and is equal toreff

o

where o is

the free space wavelength. The 10TM mode implies that the field varies one /2 cycle along the

length, and there is no variation along the width of the patch. In the Fig:2.10(a) shown below, the

microstrip patch antenna is represented by two slots, separated by a transmission line of length L

and open circuited at both the ends. Along the width of the patch, the voltage is maximum and

current is minimum due to the open ends. The fields at the edges can be resolved into normal and

tangential components with respect to the ground plane.

Fig: 2.10(a) Top view Fig: 2.10(b) bottom view


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It is seen from Fig:2.10(b) that the normal components of the electric field at the two edges along

the width are in opposite directions and thus out of phase since the patch is / 2 long and hence

they cancel each other in the broadside direction.

The tangential components (seen in Figure), which are in phase, means that the resulting fields

combine to give maximum radiated field normal to the surface of the structure.

Hence the edges along the width can be represented as two radiating slots, which are /2 apart

and excited in phase and radiating in the half space above the ground plane .The fringing fields

along the width can be modeled as radiating slots and electrically the patch of the microstrip

antenna looks greater than its physical dimensions. The dimensions of the patch along its length

have now been extended on each end by a distance L, which is given empirically by

8.0258.0

264.03.0

412.0

hW

h

W

h

L

reff

reff

where

21

1212

1

2

1

W

hrrreff

The effective length of the patch effL now becomes

effL = L +2L

For a given resonance frequency fr , the effective length effL is given as

reffr

efff

cL

2

For a rectangular microstrip patch antenna, the resonance frequency for any mnTM is given as

21

22

2

W

n

L

mcf

reff

o

Where m and n are modes along L and W respectively

For efficient radiation, the width W is given as

W= 1

2

2 reffrf

c

Where cis the free space velocity of electromagnetic waves

Since above equation does not accounts for fringing it must be modified to include edge effects

and should be computed using

reff reffrc

LL

c

L

cf

222=

rL

cq

2


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Wherer

rc

f

fq

The qfactor is referred to as the fringe factor (length reduction factor). As the substrate height

increases, fringing also increases and leads to larger separations between the radiating edges and

lower resonant frequencies.

2.5 Fringing effects

Because the dimensions of the patch are finite along the length and width, the field at the edges

of the patch undergoes fringing along length and width at the two radiating slots of a microstrip

antenna. The amount of fringing is a function of the dimensions of the patch and height of the

substrate. For the principal E-plane(x-y plane) fringing is a function of the ratio of length of the

patch L to the height h of the substrate (L/h) and the dielectric constant r of the substrate. Since

for microstrip antennas L/h >> 1, fringing is reduced; however, it must be taken into account

because it influences the resonant frequency of antenna.

Electric field lines are non homogeneous line of 2 dielectrics; typically the substrate and air.

Most of the electric field lines reside in the substrate and part of some lines exist in air. As

W/h>>1 and r >>1, the electric field lines concentrate mostly in the substrate. Fringing in this

case makes the microstrip lines look wider electrically compared to its physical dimensions.

Since some of the waves travel in the substrate and some in air, an effective dielectric constant is

introduced to account for fringing and the wave propagation in the line.

To introduce the effective dielectric constant, let us assume that the center conductor of the

microstrip line with its original dimensions and height above the ground plane is embedded into

one dielectric. The effective dielectric constant is defined as the dielectric constant of theuniform dielectric material so that the line of figure has identical electrical characteristics,

particularly propagation constant, as the actual line of figure. For a line with air above the

substrate, the effective dielectric constant has values in the range of 1< reff < r . For most

applications where the dielectric constant of the substrate is much greater than unity the value of

effective dielectric constant will be closer to the value of the actual dielectric constant of the

substrate. The effective dielectric constant is also a function of frequency. As the frequency of

operation increases, most of the electric field lines concentrate in the substrate. Therefore the

microstrip line behaves more like a homogeneous line of one dielectric (only the substrate), and

the effective dielectric constant approaches the value of dielectric constant of the substrate.For low frequencies the effective dielectric constant is essentially constant. At intermediate

frequencies its value begins to monotonically increase and eventually approach the values of

dielectric constant of the substrate. The initial values of effective dielectric constant are referred

to as the static values and they are given by

21

1212

1

2

1

W

hrrreff


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CHAPTER 3

3.1 Design Procedure

Based on the simplified formulation that has been described, a design procedure is outlinedwhich leads to practical designs of rectangular microstrip antennas. The procedure assumes that

the specified information includes the dielectric constant of the substrate r , the resonant

frequency rf , and the height of the substrate h. The procedure is as follows:-

SPECIFY: r , rf(in GHz) and h(mm)

DETERMINE: W, L

DESIGN PROCEDURE:-

1. For an efficient radiator, a practical width that leads to good radiation efficiencies is

W=1

2

2 reffrf

c

Where c is the free space velocity of em wave.

2. Determine the effective dielectric constant of the microstrip antenna using

21

1212

1

2

1

W

hrrreff

3. Once W is found, determine the extension of the length L using

8.0258.0

264.03.0

412.0

h

W

h

W

h

L

reff

reff

4. The actual length of the patch can now be determine by solving for L using

Lf

c

reffr

L

22


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Fig. 3.1 Flowchart showing the design procedure


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CHAPTER 4

4.1 Description of Software

ADS(Advance Design Systems), 3-D planar EM simulation software for electronics and antennaanalysis, a partial differential equation solver of Maxwell's equations based on the method of

moments. It is a 3-D planar electromagnetic (EM) simulator used for passive analysis. It is a full

wave, method of moments (MOM) based electromagnetic simulator for analyzing and

optimizing planar and 3D structures in a multi-layer dielectric environment. It solves Maxwell's

equation in integral form and its solutions include the wave effects, discontinuity effects,

coupling effects and radiation effects. The simulated result includes S,Y, and Z-parameters,

VSWR, RLC equivalent circuits, current field distribution, near and far field estimation,

radiation pattern etc.

4.1.1 Features of ADS Software

(a) ADS is EM Design Kit for real-time full-wave EM tuning, optimization and synthesis.

(b) Multi-fold speed improvement and multi-CPU support for much improved efficiency.

(c) Equation-based schematic-layout editor with Boolean operations for easy and flexible

geometry editing and parameterization.

(d) Lumped element equivalent circuit automatic extraction and optimization for convenientcircuit designs.

(e) Improved integration into Microwave Office from Applied Wave Research.

4.1.2 Applications of ADS

(a)MMIC Design.

(b)Signal Integrity Analysis.

(c)

RFIC Design.(d)RF & Microwave Board Design.

(e)RF System-in-Package & RF Module Design.

(f) Planar antennas such as microstrip antennas and slot antennas.

(g)Wire antennas such as various types of dipole, monopole, helix and quadrifilar antennas.

(h)Small antennas such as inverted F-antennas and its derivations.


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5.2 Design specifications for square patch

5.2.1 Base Paper

Design specification

of = 2.4GHz

r =4.6

h =1.6mm

for square patch

W=L=29.2 from equation (1)

reff =4.2 from equation (3)

L =0.731mm from equation (4)

eA =0.00526 2m from equation (6)

cZ =33.25 from equation (9)

5.2.2Design 1

of = 2.4GHz

r=4.6

h=3.2mm

W=L=29.2mm from equation (1)






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5.2.3 Design 2

of =2.4GHz

r=2.45

h=1.58mm

W=47.5mm from equation (2)

L=39mm from equation (1)





5.2

Design specification for dual patch

5.3.1 Design 1

of = 14.8GHz

r=2.08

h=1.2mm

W=8mm

L=6.3mm from equation (1)



eA =.0001711 2m from equation (6)



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5.3.2 Design 2

of = 14.8GHz

r=2.08

h=1.38mm

W=8mm

L=6.3mm from equation (1)



eA =.000197 2m from equation (6)



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CHAPTER 6

6.1

Simulation Results of square patch at 2.4 GHz.

6.1.1 Base paper

Layout of square patch

Plot of return loss with respect to frequency

m1freq=dB(design_mom..S(1,1))=-2.763

2.444GHz

1.0 1.5 2.0 2.5 3.0 3.50.5 4.0

-2.5

-2.0

-1.5

-1.0

-0.5

-3.0

0.0

Fre uenc

Mag.[d

B](H)

m1

S11

m1freq=dB(design_mom..S(1,1))=-2.763

2.444GHz

H

1.0 1.5 2.0 2.5 3.0 3.50.5 4.0

-100

0

100

-200

200

Frequency

Pha

se[deg]

S11


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Radiation pattern

6.1.2

Design 1

Layout of square patch


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Radiation pattern

m1freq=dB(TEST9_mom_a..S(1,1))=-2.618

2.475GHz

2.5 3.0 3.5 4.0 4.5 5.0 5.52.0 6.0

-2.5

-2.0

-1.5

-1.0

-0.5

-3.0

0.0

Frequency

Mag.

[dB]

m1

S11

m1freq=dB(TEST9_mom_a..S(1,1))=-2.618

2.475GHz

2.5 3.0 3.5 4.0 4.5 5.0 5.52.0 6.0

-100

0

100

-200

200

Frequency

Phase[deg]

S11


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6.1.3 Design 2

Layout of rectangular patch


m1freq=

dB(test5_mom_a..S(1,1))=-23.106

2.417GHz

2.5 3.0 3.5 4.0 4.5 5.0 5.52.0 6.0

-100

0

100

-200

200

Frequency

Phase[deg]

S11

2.5 3.0 3.5 4.0 4.5 5.0 5.52.0 6.0

-25

-20

-15

-10

-5

-30

0

Frequency

Mag.

[dB]

m1

S11

m1freq=

dB(test5_mom_a..S(1,1))=-23.106

2.417GHz


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Radiation pattern


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6.2 Simulation result of dual patch at 14.8GHz in Ku band

6.2.1 Design 1

Layout of dual patch antenna with h=1.2mm



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Radiation Parameters

6.2.2 Design 2

Layout of dual patch with h=1.38mm


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Radiation Parameters


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CHAPTER 7

7.1 Conclusion

We have implemented three designs with certain modifications in each design and we have got

better results from previous designs. The comparison among three results is given below:-

COMPARISON RESULT OF SQUARE AND RECTANGULAR PATCH AT 2.4GHz

TABLE 7.1(a)


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COMPARISON RESULTS OF DUAL PATCH AT 14.8GHz IN Ku BAND

TABLE 7.1(b)

Concluding remarks

The return loss of a dual patch antenna is investigated in free space and is compared with that of

a simple square patch antenna. The modified antenna resonates at 14.8GHz frequency in Ku

band with much improved return loss and directivity. From the above designs implemented the

best design is design1 of dual patch antenna at 14.8GHz with thickness of substarate h=1.38mm

and substrate material PTFE/Teflon with dielectric constant of 2.08. this design is useful in direct

communication with satellite.this is because of the following features:-

7.1.1 For square and rectangular patch

a)

Radiated power:- The radiated power of design 2 is 7.055mW which is much greater ascompared to that of design 1 and base paper. This increased amplitude of radiated power

depicts that antenna can work more effectively than the other radiating antennas by

emitting more amount of increased useful radiation at higher frequency which makes it

suitable for satellite communication in Ku band. It can be used in applications such as

direct broadcast television.


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b) Directivity:- In comparison to other designs, the directivity of design 2 is much greater.

This means that the beam is more directive leading to optimum design. Directivity is an

important parameter that shows how much directive the beam is as compared to ideal

isotropic antenna towards the receiving antenna. More is the directivity; more is the

power received by the receiving antenna.

c) Gain:- Gain of design 2 is highest as compared to other designs. This means that gain of

other 2 designs is less. Since gain and directivity are nearly equal, this means less losses

in the antenna. Gain is an important factor in design of antenna as it leads to the reduction

of losses in transmitting and receiving antenna.

d) Efficiency factor: -Efficiency of design 2 is slightly less than design1. However it it is

compensated by higher losses and directivity. Increased efficiency means that it can workwith higher efficiency giving directive beam. Efficiency factor depends on both the gain

of an antenna and directivity of an antenna.

e) Effective Aperture: - Effective aperture of design 2 is highest. But due to increase

efficiency factor it proves to be more useful design as compared to others.

f) Return loss: -Return loss of design 2 is lowest. It indicates that the reflected power from

the patch to the transmission line is less. Furthermore, it also indicates that the

characteristics impedance of transmission line and the patch is effectively matched.

7.1.2 For dual patch

a) Radiated power:- The radiated power of design 1 is 5.62mW which is much greater as

compared to that of design 2. This increased amplitude of radiated power depicts that

antenna can work more effectively than the other radiating antennas by emitting more

amount of increased useful radiation at higher frequency which makes it suitable for

satellite communication in Ku band. It can be used in applications such as direct

broadcast television.b) Directivity:- In comparison to other designs, the directivity of design 1 is neither more

nor less. This means that the beam is more directive leading to optimum design.

Directivity is an important parameter that shows how much directive the beam is as

compared to ideal isotropic antenna towards the receiving antenna. More is the

directivity; more is the power received by the receiving antenna.


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c) Gain:- Gain of design 1 is less as compared to design 2. This means that gain of design 1

is less. Although gain is less but it is compensated for by the other factors including the

radiated power, directivity and efficiency factor. Gain is an important factor in design of

antenna as it leads to the reduction of noise factor in transmitting and receiving antenna.

d) Efficiency factor:- Efficiency of design 1 is more as compared to design 2 thereby

making design 1 a more effective design. Increased efficiency means that it can work

with higher efficiency giving higher input to output ratio. Efficiency factor depends on

both the gain of an antenna and directivity of an antenna.

e) Effective Aperture:- Effective aperture of design 1 is less as compared to design 2

which adds to the advantage of design 1. Less effective aperture means more effective

design because useful part of the antenna that is radiating is less. Hence, more directivethe beam will be and it also adds to the added advantage of increased radiation power.

Also, during the manufacture process of antenna less material is requires which reduces

the cost of antenna.

f) Return loss:- Return loss of design 1 is less than the design2. It indicates that the

reflected power from the patch to the transmission line is less. Furthermore, it also

indicates that the characteristics impedance of transmission line and the patch is

effectively matched.


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CHAPTER 8

7.1 Conclusion

Microstrip patch antenna can provide printed radiating structure, which are electrically thin,

lightweight and low cost, is a relatively not too old. The development of system such as Satellite

communication, highly sensitive radar, radio altimeters and Missiles systems needs very light

weight antenna which can be easily attached with the systems and not make the system bulky.

These requirements are main factors to the development of the microstrip patch

antenna. By doing this we can get required results. Rectangular and circular microstrip patch

antenna are most common and very easy to analysis but to enhance their bandwidth, and toachieve multiband operation we need to make some slots on the patch and to work on defected

ground structure, defected microstrip structure and meta-material.

7.2 Suggestion for future work

In the above designs presented in this report, we have implemented them using only one feed

technique i.e., inset feed. Now, in the future designs we will try to implement other feed

techniques along with multilayer substrates to improve the radiated power. Further, we will alsotry to overcome the minor shortcomings of the above implemented designs and try to take into

consideration the polarization of antenna.


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REFERNCES

1. V.Harsha Ram Keerthi, N.Sri pravallika, P.Srinivasulu Design of C-Band Square

Microstrip Patch Antenna with Dual Feed for Radar Applications Using ADS,

International Journal of Engineering and Advanced Technology (IJEAT) ISSN: 2249

8958, Volume-2, Issue-4, April 2013.

2. Rampal Kushwaha, Design and analysis of gain for rectangular microstrip patch antenna

, International Journal of Advanced technology and engineering research

3. Constantine A. Balanis, Antenna Theory: Analysis and Design, 3rd Edition, John

Wiley and Sons, Inc. Hoboken, New Jersey 2005.

4. Yosef Yilak Woldeamanuel Design of 2.4GHz horizontally polarized microstrip

patch antenna using rectangular and circular directors and reflectors. Master of

Science, in Electrical EngineeringDepartment of Electrical Engineering, The

University of Texas at Tyler November 2012.

5. Rana, Rahul and Reddy, C V V (2009) Design of Linearly Polarized Rectangular

Microstrip Patch Antenna Using IE3D/PSO.BTech thesis.

6.

Sunil Kumar Thakur, Design and analysis of Microstrip Patch Antenna usingMetamaterial. BTech Thesis.

7. Md. Mahabub Alam, Rifat Ahmmed Aoni, Md. Toufikul Islam Gain Improvement of

Micro Strip Antenna Using Dual Patch Array Micro Strip Antenna,Journal of Emerging

Trends in Computing and Information Sciences ISSN 2079-8407,Volume-3,December

2012.

project report4

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