research article bandwidth enhancement of a backfire microstrip...

Research ArticleBandwidth Enhancement of a Backfire Microstrip PatchAntenna for Pervasive Communication

Puran Gour1 and Ravishankar Mishra2

1 NRI Institute of Information Science and Technology Bhopal 462021 India2 Sagar Institute of Science and Technology Bhopal 462036 India

Correspondence should be addressed to Puran Gour erpurangourgmailcom

Received 5 August 2013 Revised 19 May 2014 Accepted 28 May 2014 Published 30 June 2014

Academic Editor Atsushi Mase

Copyright copy 2014 P Gour and R Mishra This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

Backfire antenna 0265120582 for bandwidth enhancement is proposed and investigated The proposed antenna is fed by a 50Ω coaxialfeed The bandwidth of proposed antenna for S and C band is investigated The performance of backfire antenna is investigated byperforming numerical calculation by using various mathematical formulas to determine necessary dimensions of the antenna andsimulation by using commercially available Method of Moments software Here we design proposed geometry for 3GHz For thisgeometry we achieved 528 bandwidth for VSWR lt2 minimum return loss minus20 dB and maximum directivity 72 dBi

1 Introduction

With the development of pervasive communication band-width enhancement becomes a necessary component This isone of the important elements in the RF system for receivingand transmitting the radio wave signals from and into the airas the medium Without proper design of the antenna thesignal generated by the RF system will not be transmittedand no signal can be detected at the receiver Many types ofantenna have been designed to cater for variable applicationand to be suitable for their needs The backfire antennawas initially described in 1960 by H W Ehernspeck andmuch simplified version called the short backfire antennahas been subjected to extensive experimental studies [1]The short back fire antenna consists of large reflector 2120582 indiameter with a rim of height 025120582 and a small reflector 04120582in diameter separated by approximately 05120582 The antennabehaves like an open cavity resonator A short backfireantenna is a type of a directional antenna characterized byhigh gain relatively small size and narrow band [2 3] Thefeed location in the backfire antenna constructed upon theantenna characteristics is also examined Several attemptshave been made to enhance the bandwidth performance ofthe common dipole-fed backfire by employing various otherfeeding mechanisms with moderate success The microstrip

patch-excited short backfire antenna is superior to theseother designs in its reduced size and mass while maintainingcomparable performance [4] HW Ehernspeck has designeda backfire antenna which is constructed by placing of a bigreflector at the open end of an endfire antenna perpendic-ularly to its axis The geometry of the backfire antenna isshown in Figure 1 It consists of a source 119865 surface wavestructure 119878 and two parallel disk reflectors small reflector1198771and big reflector 119877

2which reflects the surface wave SW

2

toward the small reflector 1198771 where it is radiated from the

antenna aperture 1198811198811015840 into the space Thus the radiation ofthe antenna is directed in inverse direction in comparisonwith the radiation of the ordinary endfire antenna used as abackfire antenna prototype Because of this reason it is calledbackfire antenna [1]

2 Feeding Techniques

There are four feeding techniques that can be used whiledesigning the backfire antenna These techniques are coax-ial probeprobe coupling microstrip feed proximity (elec-tromagnetically) coupled microstrip antenna and aperturecoupled microstrip antenna feed The comparison betweenthese techniques is shown in Table 1

Hindawi Publishing CorporationInternational Journal of Antennas and PropagationVolume 2014 Article ID 560185 7 pageshttpdxdoiorg1011552014560185

2 International Journal of Antennas and Propagation

Table 1 Comparison of different feeding methods

Characteristics Line feed Coaxial feed Aperture coupled Proximity coupledConfiguration Coplanar Nonplanar Planar PlanarSpurious feed radiation More More More MorePolarization purity Good Good Excellent PoorEase of fabrication Easy Soldering and drilling Poor PoorReliability Better Poor due to soldering Good GoodImpedance matching Easy Easy Easy EasyBandwidth 2ndash5 2ndash5 2ndash5 13

R2

De1

SW2

2Ψcr

SW1

R1

De

V998400

V

F

L

Figure 1 Basic geometry of back fire antenna [1]

From the mentioned techniques in Table 1 we choosecoaxial feed to feed the proposed antenna This techniqueallows independent optimization of the feed and radiatingparts of the antenna due to the metal ground plane placedbetween them

3 Designing of Backfire Antenna

For the designing of any backfire antenna we can use mainlytwo parts

(i) Mathematical analysis

(a) For the designing of short backfire antenna(SBFA) first we have to choose the substrate ofthe antenna

(b) For numerical analysis various formulas areused

(c) And lastly for input purpose different feedingmethods are used in this we used coaxial feedline technique

(ii) Antenna design by using IE3D software

(a) For simulation part different types of softwareare used we used IE3D software

(b) Different steps are followed for the designing ofSBFA antenna

Table 2 Data sheet of different substrates

Properties LTCC FR4 Epoxy RT DuroidDielectric constant 74 436 22Loss tangent 0023 0019 00004Breakdown voltage 20ndash28 kv 55 kv gt60 kv

31 Mathematical Analysis Mathematical analysis is neces-sary for knowing the exact dimension of the patch to bedesigned By performing mathematical analysis we calculatewidth and length of the patch ground plane and reflectorsFor mathematical purpose the main important point is howwe can choose substrate The bandwidth of the short backfireantenna is directly proportional to the substrate thickness(ℎ) The bandwidth of the short backfire antenna is inverselyproportional to the square root of substrate dielectric con-stant (120576

119903) Substrate thickness is another important design

parameter Thickness of the substrate increases the fringingfield at the patch periphery like low dielectric constant andthus increases the radiated power It also gives lower qualityfactor and so higher bandwidth The low value of dielectricconstant increases the fringing field at the patch peripheryand thus increases the radiated power A small value of losstangent is always preferable in order to reduce dielectric lossand surface wave losses which increases the efficiency of theantenna [2]

There are three essential parameters that should be knownwhile performing mathematical analysis

(i) Frequency of operation (1198910) the resonant frequency

of the antenna must be selected appropriately(ii) Dielectric constant of the substrate (120576

119903) the dielectric

material selected for our design for microstrip patchand ground plane is FR4 which has a dielectricconstant of 43 (Table 2) Also an effective dielectricconstant (120576eff) must be obtained in order to accountfor the fringing and the wave propagation in the line

(iii) Height of dielectric substrate (ℎ) the height of thedielectric substrate is selected as 15mm

Formulae used for mathematical calculations are

119882 =119888

2119891radic(120576119903+ 1) 2

120576119903eff = (120576119903+ 1

2) + (120576119903minus 1

2) [1 + 12

ℎ

119882]

minus12

International Journal of Antennas and Propagation 3

Δ119871 = 0412ℎ(120576119903eff + 03) ((119882ℎ) + 0264)

(120576119903eff + 0258) ((119882ℎ) + 08)

119871 =119888

2119891radic120576119903effminus 2Δ119871

1198710= 119871 + 6ℎ

1198820= 119882 + 6ℎ

(1)

where119891= operating frequency 120576119903=permittivity of the dielec-

tric 120576119903eff = effective permittivity of the dielectric119882 = patchrsquos

width 119871 = patchrsquos length ℎ = thickness of the dielectric 1198710=

length of ground plate and1198820= width of ground plate

32 Effect of Substrate While performingmathematical anal-ysis effect of substrate is also considered Some of the impor-tant points that needed to be considered are as follows [5ndash8]

(i) The bandwidth ofmicrostrip patch antenna is directlyproportional to the substrate thickness (ℎ) andinversely proportional to the square root of substratedielectric constant (120576)

(ii) Thick substrate increases the fringing field at thepatch periphery and thus increases the radiatedpower

(iii) A small value of loss tangent is always preferable inorder to reduce dielectric loss and surface wave lossand it increases the efficiency of antenna

(iv) Low dielectric constant is used which has very lowwater absorption capability

33 Antenna Design by Using IE3D Software The proposedantenna is designed in Flame Retardant 4 (FR4) such thatthe return loss directivity and the radiation pattern can beobtained by using the EM Simulator IE3D (version 90) soft-ware Based on the simulations andmathematical calculationwe find the length and width of rectangular microstrip patchof short backfire antenna which is calculated as shown inTables 3 and 4

4 Simulation and Results

The antenna was simulated by IE3D software which uses theMethod ofMoments approach in itsmodeling equations withthe final patch obtained shown in Figure 2

The antenna geometry consist of two reflector one rectan-gular and other circular and between thempatch is connected(Figures 3 and 4) The 3D view of the proposed antenna is asshown in Figure 5

The obtained minimum value of the antenna return lossis minus20 dB at the frequency of 55 GHz as shown in Figure 6Thus the bandwidth obtained from the return loss result is528

Moreover VSWR is a measure of how well matched is theantenna to the cable impedance A proposed antenna wouldhave aVSWRof less than 2 for 45ndash79GHzThis indicates lesspower is reflected back from source VSWR obtained fromthe simulation is less than 2 which is approximately equal to

L6

L5

L4

L3

L2

L1

W4W1

W2

W5

W3W6

Figure 2 Proposed excitation structure where the feed is to begiven

Figure 3 Geometry of proposed antenna with main rectangularreflector

1

Figure 4 Geometry of proposed antenna


Table 3 Mathematical calculation for the proposed antenna

Serialnumber Parameters Values for

proposed antenna

1 Design frequency (1198910) 3GHz

2 Dielectric constant (120576119903) 43

3 Height of substrate (ℎ) 15mm

4 Loss tangent of FR4 0019

5 Width of rectangular patch (119882) 307148mm

6 Length of rectangular patch (119871) 237388mm

7 Width of ground plane (1198820) 397148mm

8 Length of ground plane (1198710) 327388mm

9 Diameter of big reflector (119889) 50mm

10 Height of big reflector (119867119903) 25mm

11Feed location119883119891(along length)119884119891(along width)

119883119891= 6975

119884119891= minus104

12 Length of antenna (119871119860) 265mm

Table 4 Optimal parameter values of the antenna

Serial number Parameters Values of proposed geometry (mm)1 Length 1198711 14 (0014120582

0)

2 Length 1198712 4 (0041205820)

3 Length 1198713 4 (0041205820)

4 Length 1198714 4 (0041205820)

5 Length 1198715 9 (0091205820)

6 Length 1198716 12 (0121205820)

7 Width1198821 35 (00351205820)

8 Width1198822 35 (00351205820)

9 Width1198823 15 (00151205820)

10 Width1198824 155 (01551205820)

11 Width1198825 105 (01051205820)

12 Width1198826 1 (0011205820)

11 1 as shown in Figure 7 This is considered a good value asthe level of mismatch is not very high because high VSWRimplies that the port is not properly matched

The maximum directivity of proposed antenna is 72 dBiat 75 GHz (Figure 8)

The maximum gain of proposed antenna is 6 dBi at75 GHz (Figure 9)

The 3D radiation pattern of the antenna at frequency335GHz (out of antenna frequency bandwidth) is shown inFigures 10 and 11 It can be observed from this radiation thatthe design antenna has stable radiation pattern throughoutthe whole operating band

Figure 5 3D view of proposed antenna

minus8

minus10

minus12

minus14

minus16

minus18

minus20

35 4 45 5 55 6 65 7 75 8

dB[S(11)]

(dB)

Frequency (GHz)

BW = 225 BW = 528

Figure 6 Return loss for proposed antenna

VSWR lt 2

Frequency (GHz)

22

2

18

16

14

12

1

VSW

R

35 45 54 55 6 65 7 75 8

Port 1

Figure 7 VSWR curve for proposed antenna


Table 5 Basic electrical characteristics of the proposed antenna

Serial number Parameters Value1 Minimum 119878

11minus20 dB at 55 GHz

2 Bandwidth 528 between (46ndash79) GHz3 VSWR lt20 between (46ndash79) GHz4 Maximum directivity 72 dBi at 75 GHz5 Maximum gain 6 dBi at 75 GHz6 Center frequency 119891

0= 05(119891min + 119891max) 625GHz

Table 6 Comparison between the classic SBFA and the proposed antenna

Serial number Dimensionparameter AntennaClassic SBFA Proposed antenna

1 Center wavelength 1205820

48mm2 Big reflector diameter 1198632 2 120582

050mm (104 1205820)

3 Small rectangular dimension1198631 0443 1205820

36227mm (0755 1205820)4 Length of the antenna 119871

11986005 1205820

265mm (0522 1205820)5 Distance source small reflector 1198891 025 120582

015mm (0031 1205820)

6 Distance source big reflector 1198892 025 1205820

25mm (0521 1205820)7 Maximum gain 119866 13 dBi 6 dBi8 Bandwidth bw 4ndash5 528

Max directivity72dBi at75GHz

Frequency (GHz)35 45 54 55 6 65 7 75 8

10

9

8

7

6

5

4

3

2

1

0

Maximum directivity

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

Figure 8 Directivity versus frequency curve for proposed antenna

5 Validation

To ensure our graphically simulated results are reliable wehave also validated our results with experimental resultsobtained from other source reported by Asad et al [4] Itis evident from [4] that the VSWR bandwidth is 2128 insimulation with the finite element method based softwaretool and 528 at the 46 to 79GHz of the reported simulationresult Thus it has depicted that the VSWR bandwidth spansmore in simulated results as compared to reported resultsThe antenna is validated by using Agilent Network AnalyzerN9923A whose hardware result is approximately the same assimulation results as shown in Figures 12 13 and 14

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

Frequency (GHz)35 45 54 55 6 65 7 75 8

Maximum gain

Gain versus frequency

Figure 9 Gain curve for proposed antenna

The basic electrical characteristics of the proposedantenna are summarized in Table 5

A comparison between the dimension and some electricalcharacteristics of the classic SBFA with optimum dimensionand the proposed antenna is accomplished in Table 6

It is seen from Tables 3 5 and 6 that the used nonop-timum (smaller) dimension of the big reflector and nonop-timum place of the source (feed) in the proposed antennashifts the center frequency 2 times from the design frequency(from 3GHz to 625GHz) and decreases five times (with7 dB) its gain but the widebandmicrostrip excitation leads toa dramatic increase of the antenna bandwidth approximately12 times (from 45 to 528)


Figure 10 Smith chart for proposed antenna

Figure 11 3D radiation pattern

6 Conclusion

In this paper we presented the design of the backfire rect-angular patch antenna for bandwidth enhancement coveringthe 3GHzminus8GHz frequency spectrum It has been shownthat this design of the back fire rectangular patch antennaproduces a bandwidth of approximately 528 with a stableradiation pattern within the frequency range The designantenna exhibits a good impedance matching of approxi-mately 50 Ohms at the center frequency This antenna canbe easily fabricated on FR4 substrate material due to its smallsize and thicknessThe simple coaxial feeding technique usedfor the design of this antennamakes its antenna a good choicein many communication systems

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Figure 12 Side view of proposed antenna

Figure 13 Ground plane of proposed antenna

Figure 14 Hardware testing on Agilent N9923A

Acknowledgment

The authors would like to express their thanks to the anony-mous referees for their helpful comments and suggestionswhich improve the presentation of the paper

References

[1] G S Kirov and H D Hristov ldquoStudy of backfire antennasrdquoJournal of Microwaves Optoelectronics and ElectromagneticApplications vol 10 no 1 pp 1ndash12 2011

[2] C A Balanis AntennaTheory John Wiley amp Sons 3rd edition2005


[3] S Qu J Li Q Xue C H Chan and S Li ldquoWideband and unidi-rectional cavity-backed folded triangular bowtie antennardquo IEEETransactions on Antennas and Propagation vol 57 no 4 pp1259ndash1263 2009

[4] M J Asad M Zafrullah M K Islam and M Amin ldquoDevel-opment of short backfire antenna fed by H-shaped excitationstructuresrdquo in Proceedings of the 17th International Conferenceon Telecommunications (ICT rsquo10) pp 449ndash454 April 2010

[5] G S Kirov ldquoDesign of short backfire antennasrdquo IEEE Antennasand Propagation Magazine vol 51 no 6 pp 110ndash120 2009

[6] R Li D C Thompson J Papapolymerou J Laskar and MM Tentzeris ldquoA circularly polarized short backfire antennaexcited by an unbalance-fed cross aperturerdquo IEEE Transactionson Antennas and Propagation vol 54 no 3 pp 852ndash859 2006

[7] R Li D Thompson J Papapolymerou J Laskar and M MTentzeris ldquoA new excitation technique for wide-band shortbackfire antennasrdquo IEEE Transactions on Antennas and Prop-agation vol 53 no 7 pp 2313ndash2320 2005

[8] G S Kirov G T Chervenkov andC D Kalchev ldquoAperture cou-pled microstrip short backfire antennardquo Journal of ElectricalEngineering vol 63 no 2 pp 75ndash80 2012

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Active and Passive Electronic Components

Control Scienceand Engineering

Journal of



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Submit your manuscripts athttpwwwhindawicom

VLSI Design



Shock and Vibration


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The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

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Modelling amp Simulation in EngineeringHindawi Publishing Corporation httpwwwhindawicom Volume 2014


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Propagation




Navigation and Observation



DistributedSensor Networks



Table 1 Comparison of different feeding methods

Characteristics Line feed Coaxial feed Aperture coupled Proximity coupledConfiguration Coplanar Nonplanar Planar PlanarSpurious feed radiation More More More MorePolarization purity Good Good Excellent PoorEase of fabrication Easy Soldering and drilling Poor PoorReliability Better Poor due to soldering Good GoodImpedance matching Easy Easy Easy EasyBandwidth 2ndash5 2ndash5 2ndash5 13

R2

De1

SW2

2Ψcr

SW1

R1

De

V998400

V

F

L

Figure 1 Basic geometry of back fire antenna [1]

From the mentioned techniques in Table 1 we choosecoaxial feed to feed the proposed antenna This techniqueallows independent optimization of the feed and radiatingparts of the antenna due to the metal ground plane placedbetween them

3 Designing of Backfire Antenna

For the designing of any backfire antenna we can use mainlytwo parts

(i) Mathematical analysis

(a) For the designing of short backfire antenna(SBFA) first we have to choose the substrate ofthe antenna

(b) For numerical analysis various formulas areused

(c) And lastly for input purpose different feedingmethods are used in this we used coaxial feedline technique

(ii) Antenna design by using IE3D software

(a) For simulation part different types of softwareare used we used IE3D software

(b) Different steps are followed for the designing ofSBFA antenna

Table 2 Data sheet of different substrates

Properties LTCC FR4 Epoxy RT DuroidDielectric constant 74 436 22Loss tangent 0023 0019 00004Breakdown voltage 20ndash28 kv 55 kv gt60 kv

31 Mathematical Analysis Mathematical analysis is neces-sary for knowing the exact dimension of the patch to bedesigned By performing mathematical analysis we calculatewidth and length of the patch ground plane and reflectorsFor mathematical purpose the main important point is howwe can choose substrate The bandwidth of the short backfireantenna is directly proportional to the substrate thickness(ℎ) The bandwidth of the short backfire antenna is inverselyproportional to the square root of substrate dielectric con-stant (120576

119903) Substrate thickness is another important design

parameter Thickness of the substrate increases the fringingfield at the patch periphery like low dielectric constant andthus increases the radiated power It also gives lower qualityfactor and so higher bandwidth The low value of dielectricconstant increases the fringing field at the patch peripheryand thus increases the radiated power A small value of losstangent is always preferable in order to reduce dielectric lossand surface wave losses which increases the efficiency of theantenna [2]

There are three essential parameters that should be knownwhile performing mathematical analysis

(i) Frequency of operation (1198910) the resonant frequency

of the antenna must be selected appropriately(ii) Dielectric constant of the substrate (120576

119903) the dielectric

material selected for our design for microstrip patchand ground plane is FR4 which has a dielectricconstant of 43 (Table 2) Also an effective dielectricconstant (120576eff) must be obtained in order to accountfor the fringing and the wave propagation in the line

(iii) Height of dielectric substrate (ℎ) the height of thedielectric substrate is selected as 15mm

Formulae used for mathematical calculations are

119882 =119888

2119891radic(120576119903+ 1) 2

120576119903eff = (120576119903+ 1

2) + (120576119903minus 1

2) [1 + 12

ℎ

119882]

minus12


Δ119871 = 0412ℎ(120576119903eff + 03) ((119882ℎ) + 0264)

(120576119903eff + 0258) ((119882ℎ) + 08)

119871 =119888

2119891radic120576119903effminus 2Δ119871

1198710= 119871 + 6ℎ

1198820= 119882 + 6ℎ

(1)
















L6

L5

L4

L3

L2

L1

W4W1

W2

W5

W3W6



1





proposed antenna












119883119891= 6975

119884119891= minus104




0)

2 Length 1198712 4 (0041205820)

3 Length 1198713 4 (0041205820)

4 Length 1198714 4 (0041205820)

5 Length 1198715 9 (0091205820)

6 Length 1198716 12 (0121205820)

7 Width1198821 35 (00351205820)

8 Width1198822 35 (00351205820)

9 Width1198823 15 (00151205820)

10 Width1198824 155 (01551205820)

11 Width1198825 105 (01051205820)

12 Width1198826 1 (0011205820)






minus8

minus10

minus12

minus14

minus16

minus18

minus20

35 4 45 5 55 6 65 7 75 8

dB[S(11)]

(dB)

Frequency (GHz)

BW = 225 BW = 528


VSWR lt 2

Frequency (GHz)

22

2

18

16

14

12

1

VSW

R

35 45 54 55 6 65 7 75 8

Port 1







0= 05(119891min + 119891max) 625GHz





050mm (104 1205820)



11986005 1205820


015mm (0031 1205820)




Frequency (GHz)35 45 54 55 6 65 7 75 8

10

9

8

7

6

5

4

3

2

1

0

Maximum directivity

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)


5 Validation


10

9

8

7

6

5

4

3

2

1

0

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

Frequency (GHz)35 45 54 55 6 65 7 75 8

Maximum gain









6 Conclusion







Acknowledgment


References












RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










Δ119871 = 0412ℎ(120576119903eff + 03) ((119882ℎ) + 0264)

(120576119903eff + 0258) ((119882ℎ) + 08)

119871 =119888

2119891radic120576119903effminus 2Δ119871

1198710= 119871 + 6ℎ

1198820= 119882 + 6ℎ

(1)
















L6

L5

L4

L3

L2

L1

W4W1

W2

W5

W3W6



1





proposed antenna












119883119891= 6975

119884119891= minus104




0)

2 Length 1198712 4 (0041205820)

3 Length 1198713 4 (0041205820)

4 Length 1198714 4 (0041205820)

5 Length 1198715 9 (0091205820)

6 Length 1198716 12 (0121205820)

7 Width1198821 35 (00351205820)

8 Width1198822 35 (00351205820)

9 Width1198823 15 (00151205820)

10 Width1198824 155 (01551205820)

11 Width1198825 105 (01051205820)

12 Width1198826 1 (0011205820)






minus8

minus10

minus12

minus14

minus16

minus18

minus20

35 4 45 5 55 6 65 7 75 8

dB[S(11)]

(dB)

Frequency (GHz)

BW = 225 BW = 528


VSWR lt 2

Frequency (GHz)

22

2

18

16

14

12

1

VSW

R

35 45 54 55 6 65 7 75 8

Port 1







0= 05(119891min + 119891max) 625GHz





050mm (104 1205820)



11986005 1205820


015mm (0031 1205820)




Frequency (GHz)35 45 54 55 6 65 7 75 8

10

9

8

7

6

5

4

3

2

1

0

Maximum directivity

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)


5 Validation


10

9

8

7

6

5

4

3

2

1

0

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

Frequency (GHz)35 45 54 55 6 65 7 75 8

Maximum gain









6 Conclusion







Acknowledgment


References












RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












proposed antenna












119883119891= 6975

119884119891= minus104




0)

2 Length 1198712 4 (0041205820)

3 Length 1198713 4 (0041205820)

4 Length 1198714 4 (0041205820)

5 Length 1198715 9 (0091205820)

6 Length 1198716 12 (0121205820)

7 Width1198821 35 (00351205820)

8 Width1198822 35 (00351205820)

9 Width1198823 15 (00151205820)

10 Width1198824 155 (01551205820)

11 Width1198825 105 (01051205820)

12 Width1198826 1 (0011205820)






minus8

minus10

minus12

minus14

minus16

minus18

minus20

35 4 45 5 55 6 65 7 75 8

dB[S(11)]

(dB)

Frequency (GHz)

BW = 225 BW = 528


VSWR lt 2

Frequency (GHz)

22

2

18

16

14

12

1

VSW

R

35 45 54 55 6 65 7 75 8

Port 1







0= 05(119891min + 119891max) 625GHz





050mm (104 1205820)



11986005 1205820


015mm (0031 1205820)




Frequency (GHz)35 45 54 55 6 65 7 75 8

10

9

8

7

6

5

4

3

2

1

0

Maximum directivity

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)


5 Validation


10

9

8

7

6

5

4

3

2

1

0

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

Frequency (GHz)35 45 54 55 6 65 7 75 8

Maximum gain









6 Conclusion







Acknowledgment


References












RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation














0= 05(119891min + 119891max) 625GHz





050mm (104 1205820)



11986005 1205820


015mm (0031 1205820)




Frequency (GHz)35 45 54 55 6 65 7 75 8

10

9

8

7

6

5

4

3

2

1

0

Maximum directivity

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)


5 Validation


10

9

8

7

6

5

4

3

2

1

0

(dBi

)

10

9

8

7

6

5

4

3

2

1

0

(dBi

)

Frequency (GHz)35 45 54 55 6 65 7 75 8

Maximum gain









6 Conclusion







Acknowledgment


References












RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












6 Conclusion







Acknowledgment


References












RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation


















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation









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