Single Patch Antenna And Array Antenna Computer Science Essay

This paper presents the design of Single Rectangular Patch Antenna and Rectangular Patch Array Antenna at frequence of 2.5GHz. The addition of Patch Antenna can be increased by utilizing the Array technique. The designed aerial is simulated by utilizing CST Studio Suite 2010: Microwave Studio package.

NOWADAYS, the big demand by end user for incorporate wireless digital application has increased the usage of microstrip aerial. The microstrip aerial is preferred due to its low profile, light weight and low volume [ 1 ] . Microstip aerials are widely used for commercial applications such as direct broadcast orbiter communicating ( DBS ) , Global Positioning System ( GPS ) and distant detection applications. With its little size and high denseness packaging advantages, the microstrip engineering is suited for RFICs ( Radio Frequency Integrated Circuits ) and MMICs ( Microwave Monolithic Integrated Circuits ) .

However, it has its disadvantages of surface moving ridges coevals, common yoke, matching with other constituents, narrow bandwidth, loss due to feed mechanism, low efficiency, low power evaluation, specious radiations, higher side lobes and low scanning abilities [ 1 ] . In order to get the better of the issues of addition that faced by microstip aerial, array technique is used. Patch Array Antenna is design to file away higher addition than Single Patch Antenna which shown in Figure 1. It is on the construct of the larger the figure of antenna elements, the better the addition of antenna array is due to its electrical size. Therefore, in this paper, the addition of a Single Patch Antenna is improved by utilizing Patch Array Antenna.

ANTENNA DESIGN

Single Rectangular Patch Antenna

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Figure 1: Single Patch Antenna

Rectangular Patch Array Antenna

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Figure 2: Array Patch Antenna

The same equation was used when ciphering the dimension of the array aerial. The feed line of array aerial was calculated by utilizing the one-fourth wave transformer method.

Simulation

Rectangular Single Patch Antenna

Figure 3: Return Loss for Single Patch Antenna

By mentioning to Figure 3, the return loss for the rectangular individual spot aerial is -43.6446dB at 2.5GHz.

Figure 4: Radiation Form

From Figure 4, HPBW = 93 & A ; deg ; , FNBW = 268 & A ; deg ;

Figure 5: Simulated Addition

Fake addition for the individual spot aerial = 3.385dB

Fake directionality = 6.692dBi

Rectangular Array Antenna

Figure 6: Return Loss for Array Patch Antenna

From Figure 6, the return loss for the array spot aerial is -16.30616dB at 2.5GHz.

Figure 7: Radiation Form

From Figure 7, HPBW = 65 & A ; deg ; , FNBW = 299 & A ; deg ;

Figure 8: Simulated Addition

Fake addition for array spot aerial = 5.936dB

Fake directionality = 9.767dBi

Measurement

Single Patch Antenna

Figure 9: Measured Return Loss

The fading of web analyser = 0.42dB

Return loss = -24.647dB at 2.708GHz

Table 1: Power Received by the Single Patch Antenna

Angle ( & A ; deg ; )

Power ( dBm )

0

-35.99

30

-37.88

60

-42.46

90

-50.70

120

-55.12

150

-50.96

180

-48.71

210

-52.02

240

-58.88

270

-49.75

300

-43.09

330

-38.69

360

-35.99

By mentioning to Figure 10,

HPBW= 70 & A ; deg ; , FNBW=240 & A ; deg ;

Directivity = 22.89dB at the angle of 240 & A ; deg ;

To cipher the addition for individual spot aerial,

From spectrum analyser,

Figure 10: Measured Radiation Pattern

Array Patch Antenna

Figure 11: Measured Return Loss

The fading of web analyser = 0.42dB

Return loss = -13.917dB at 2.758GHz

Table 1: Power Received by the Patch Array Antenna

Angle ( & A ; deg ; )

Power ( dBm )

0

-36.76

30

-42.39

60

-77.98

90

-56.17

120

-50.36

150

-49.83

180

-52.80

210

-51.24

240

-48.68

270

-52.69

300

-56.03

330

-44.37

360

-36.76

Figure 12: Measured Radiation Pattern

By mentioning to Figure 12,

HPBW = 36 & A ; deg ; , FNBW = 87 & A ; deg ;

Directivity = 41.22dB at the angle of 60 & A ; deg ;

To cipher the addition for individual spot aerial,

From spectrum analyser,

Discussion

In Table 3 below, we observed the comparing between the simulation and measurement consequences of the aerial parametric quantities for the individual and array spot aerial. The aerial parametric quantities that will be analyzed and discussed are return loss ( S11 ) , receiver addition ( GR ) , directionality ( D ) , HPBW and FNBW.

Table 3: Comparison between simulation and measuring

for individual and array spot aerial

Antenna Parameters

Simulation

Measurement

Single spot

Array spot

Single spot

Array spot

S11

( dubnium )

-43.65 at 2.5GHz

-16.31 at 2.5GHz

-24.27 at 2.708GHz

-14.10 at 2.758GHz

GR

3.385dB at 2.5GHz

5.936dB at 2.5GHz

2.667dB at 2.69GHz

1.325dB at 2.80GHz

Calciferol

9.392dB

12.46dB

22.89dB at 240 & A ; deg ;

41.22dB at 60 & A ; deg ;

HPBW

93 & A ; deg ;

65 & A ; deg ;

70 & A ; deg ;

36 & A ; deg ;

FNBW

268 & A ; deg ;

299 & A ; deg ;

240 & A ; deg ;

87 & A ; deg ;

From Figure 3 and Figure 6, the designed individual spot aerial and array spot aerial have a return loss of -43.6446dB and -16.30616dB at 2.5GHz severally, whereby both return loss are less than -10dB. This means that the electromagnetic moving ridge being transmitted is more than 90 % of injected signal. In other word, there is less than 10 % of signal being reflected due to mismatch. The designed individual spot aerial and array spot aerial have 99.99 % and 97.52 % of efficiency severally. When the return loss of an aerial is close to -?dB, the aerial will hold better efficiency.

The fake addition for individual spot aerial is 3.385dB while the fake addition for array spot aerial is 5.936dB ; there is 2.551dB addition in the addition with array method. Besides, the radiation forms besides show that the directionality for array spot aerial is better than the individual spot aerial. The fake directionality for individual spot aerial is 6.692dBi while for array spot aerial is 9.767dBi, which show an addition of 3.075dBi in directionality.

In the measuring, we could detect that the mensural addition in the array aerial is 50.32 % lesser than that of individual spot aerial as shown in Table 3. Theoretically, the addition of the array spot aerial should be higher than that of individual spot. This is because the array method can increase the addition of the individual spot. However, the measuring shows that the addition of the individual spot is non increased in the array spot compared to the simulation consequence whereby the addition for the array spot aerial is higher than the individual spot. The measuring for the addition in the individual and array spot is taken at different centre frequences, 2.69GHz and 2.80GHz than the defined centre frequence of 2.5GHz. The improper scenes of the specifications of FR4 board in the simulation and defects during the fiction could hold caused the centre frequence to switch approximately 0.1~0.3GHz. Other than that, imperfect matching between aerial and overseas telegram could hold caused the power received by the array spot aerial to be lower than that of individual spot because the standard power will impact the addition of the receiving system.

For measurement portion, the mensural return loss for individual spot aerial is -24.474dB at 2.708GHz while the return loss for array spot aerial is -14.097dB at 2.758GHz. There are a somewhat frequence switching in both return loss which is about 0.2GHz. These consequences may be caused by the improper fiction process and besides due to the oxidization happened to the surface of the individual and array spot aerial.

For the individual spot, we could see the comparing between the simulation and measurement consequences from Figure 4 and 10. The mensural HPBW and FNBW in Figure 10 are 24.73 % and 10.45 % lower than that of simulation. As for the directionality of the individual spot, we observed that the mensural directionality is 13.50dB higher than the fake directionality of 9.392dB as shown in Table 3. The addition obtained from measuring is 21.21 % lower than that of simulation. The shifting of the halfway frequence from 2.5 GHz to 2.69GHz may hold caused the differences in the HPBW, FNBW, directionality and addition in the individual spot.

For the array spot aerial, the mensural addition is 1.325dB at centre frequence, 2.80GHz which is 77.68 % lower than that of simulation as shown in Table 3. Furthermore, there is a difference of 28.76dB in directionality of the array whereby the mensural directionality is higher than the simulation consequence. The mensural HPBW is 44.62 % lower than the fake HPBW, 65 & A ; deg ; . For the FNBW, the measured angle is smaller compared to simulation whereby its angle is 87 & A ; deg ; and the difference between simulation and measuring is 70.90 % .

Decision

In this study, the individual and array spot aerials have been designed, simulated, fabricated and measured. The public presentation of both the individual and array spot are observed and analyzed in footings of addition, directionality, HPBW and FNBW. The array spot has shown betterments in footings increased directionality and narrower HPBW and FNBW compared to the individual spot at frequence 2.758GHz. However, the addition of array spot is non increased compared to the addition of the individual spot. This is due to the shifting of the Centre frequence about 0.2GHz from the defined frequence of 2.5GHz. The addition of the individual spot aerial can be improved by utilizing array method but utilizing more than two patch elements. A higher addition and directionality can be achieved by increasing the figure of patch elements.