**International Journal of Emerging Technology and Advanced Engineering **

**Website: www.ijetae.com (ISSN 2250-2459,ISO 9001:2008 Certified Journal, Volume 4, Issue 11, November 2014)**

### 221

## Performance Comparison of Various Single Patch Microstrip

## Patch Antenna for High Speed Wireless Applications

### F. Shobana

1### , K. Ashwini Priyanka

2### , K. Meena Alias Jeyanthi

3*1,2 _{PG Student, }3_{Professor, PSNA College of Engineering &Technology, Dinidigul, Tamilnadu, India. }*

**Abstract-In this paper we propose a simple, low cost and ****accurate model of microstrip antennas which is suitable for **
**applications in GHz range. The design parameters are **
**optimized to achieve the compact dimensions as well as the **
**best possible characteristics such as return loss at center **
**frequency, high radiation efficiency and high gain. In this **
**paper,various shapes of antennas are designed, simulated, **
**analyzed and fabricated on a FR4 substrate and its **
**performance is tested interms of return loss. The proposed **
**structures ** **shows ** **VSWR ** **<2 ** **with ** **omni-directional **
**characteristics and good radiation efficiency for the centre **
**frequency of 800MHz to 3.925GHz. The simulation has been **
**performed using ADS momentum simulator. It has been **
**observed that the printed antennas shows better performance **
**for MIMO, multi band and RFID applications. **

**Keywords-Micro strip antenna, ADS (Advanced Design ****System), Rectangular patch, FR4 substrate. **

I. INTRODUCTION

MIMO transmission is one of the promising antenna technologies used for wireless communications. When the transceiver uses more than one antenna, the antennas must be placed atleast half of the carrier wavelength apart, in order to transmit/receive uncorrelated signals. Not only for the MIMO applications, there numerous applications are quotable for microstrip antennas such as medical, defense, radar and RFID etc. Among many applications, RFID technology has a bright future for wireless communication through a network such as the internet. But the design of the antenna suffers from narrow bandwidth in both bands. An antenna is an electrical device which converts electric power into radio waves and viceversa. It is usually used with aradio transmitter or radio receiver. Antennas are essential components of all equipment that uses radio waves.Among many types of antennas, microstrip antenna have attracted a lot of attention due to rapid growth in wireless communication due to its lightweight,low volume,low profile, low fabrication cost and ease of integration with microwave integrated circuits (MICs). A Patch antenna (also known as a rectangular microstrip antenna consists of a radiating patch of any geometry ( e.g Rectangle, Square, Triangle, Circle, Ring etc) on one side and dielectric substrate in the other side.

The Patch is made up of conducting material of Gold or Copper, which can take any possible shapes. The Radiating Patch and the feed lines is photo etched on the dielectric substrate.

*Different Shapes of the Patch Antenna *

Rectangular patch Square patch

Isosceles right angled Equilateral triangular Triangular patch patch

Circular patch Ring shaped patch

II. DESIGN AND SIMULATION

*A. Design equations of rectangular patch antenna *

The rectangular patch antenna is the simplest form of patch antenna and usually designed to operate the resonance.[1] It is very easy to analyze using both the transmission line and cavity models which are most accurate for thin substrates.

*Calculation of the width (W) *

The width of the Patch antenna is should satisfy the condition

*r*

*W*

###

###

### /

###

**--**--(1)*Where,*

**International Journal of Emerging Technology and Advanced Engineering **

**Website: www.ijetae.com (ISSN 2250-2459,ISO 9001:2008 Certified Journal, Volume 4, Issue 11, November 2014)**

### 222

*The width of the Patch is given by *

* ----(2) *
*Where, *

*C –velocity of light (3*108 meter/sec) *

*Calculation of Effective Dielectric Constant (εreff) *
The Effective Dielectric Constant of the substrate is
defined as the fraction with which the dielectric constant of
the substrate varies when the metal patch is placed or
embedded in it. The Effective Dielectric Constant is given
by

*---(3) *

*Calculation of the Effective Length (Leff) *

The Effective Length of the Patch is defined as the length over which the electric field exists. The Effective Length of the Patch is given by

* ---(4) *
*H field pattern: *

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*---(5)*

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*----(6)*

*B. Design of rectangular patch antenna with actual *
*dimensions*

**Figure 1 Return loss curve for rectangular patch antenna **

*C. Construction of modified rectangular patch antenna *
*with modified dimensions *

**Figure 2 return loss curve for rectangular patch antenna **

Figure 2 represents return loss for rectangular patch antenna which shows simulated s11 value of -33 dB

**International Journal of Emerging Technology and Advanced Engineering **

**Website: www.ijetae.com (ISSN 2250-2459,ISO 9001:2008 Certified Journal, Volume 4, Issue 11, November 2014)**

### 223

*D. Triangular Patch Antenna *

The triangular geometry of microstrip antenna is one of the most common shapes having a wide range of wireless applications ranging from circuit element to wireless antennas. It has the advantage of occupying less metalized area on substrate then other configurations.

*E. Design of triangular patch antenna with actual *
*dimensions *

**Figure 4 return loss curve for triangular patch antenna **

**Figure 5 triangular patch antenna is tested and fabricated by using **
**network analyzers **

*F. Circular Patch Antenna *

Circular patch antenna is a popular patch antenna used for various purposes in modern technology. Itis used not only the single element but also in array form and it is analyzed by treating the patch, ground plane and the material between the two as a circular cavity.[2]

*The electric field equation for circular patch antenna , *

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* ---(7) *

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* ---(8) *
*G. Design of circular patch antenna *

**Figure 6 return loss curve for circular patch antenna **

*H. Construction of a modified circular microstrip patch *
*antenna *

**Figure 7 return loss curve for circular patch antenna **

Figure 7 represents return loss for circular patch antenna which shows simulated s11 value of -22 dB

**International Journal of Emerging Technology and Advanced Engineering **

### 224

*I. Construction of actual semi-circle patch antenna: *

**Figure 9 return loss curve for semi-circular patch antenna **

*J. Construction of modified semi-circular patch antenna: *

**Figure 10 return loss curve for semi-circular patch antenna **

**Figure 11 return loss curve for semi-circular patch antenna is **
**measured **

III. RESULTS AND DISCUSSION

**Table 1: **

**Comparison of Various Microstrip Antennas **

**Table 2: **

**Comparison of Various Microstrip Antennas **

**Parameters ** **Circular ** ** Semi **
**Circular **

Resonant Frequency 801.8040MHz 801.808MHz Dielectric Constant Of

The Substrate (Εr) _{4.32 } _{4.32 }

Tangent Loss 0.01 0.01

Height Of Dielectric Substrate (H)

4.5mm 1mm

Simulated S11 (dB) -22 -22

Measured S11 (dB) _{-20 } _{-19 }
**Parameters ** **Rectangular ** **Triangular **

Resonant Frequency 3925.6MHz 1.4071GHz Dielectric Constant Of

The Substrate (Εr) _{4.32 } _{4.32 }

Tangent Loss 0.01 0.01

Height Of Dielectric Substrate (H)

3.5mm 2.6mm

Simulated S11 (dB) -33 -38

**International Journal of Emerging Technology and Advanced Engineering **

### 225

Various shapes of the antenna are designed using ADS momentum simulator. The performance of the antenna can be characterized by return loss and radiation efficiency. These parameters are simulated and tested by using Agilent on-field Vector network analyzer N9926A and the results are tabulated below. From the table both the simulated and measured values are similar. Hence it is validated.

IV. CONCLUSION

These designed antenna are very simple, cost effective and high efficiency for the applications in GHz frequency ranges. The optimum design parameters (i.e. dielectric material, height of the substrate, operating frequency) are used to achieve the compact dimensions and high radiation efficiency. The measured results agreed with the simulated values. The antenna presented here proves to be electrically small and is the best candidate for MIMO, RFID and all other wireless applications. It would also be possible to design an antenna operating in any other frequency bands by changing the design parameters.

In future, we will investigate the spiral designs and slots in the existing design with different feeding techniques which seem to be having more improved performances for the specified applications. At the same time we will merge more than two patch elements operating at different frequencies by using quarter wavelength transformer method within an

arraynetwork configurations to get multiband support.

REFERENCES

[1] Magthoom Fouzia Y, Dr.K.Meena alias Jeyanthi, 2014Design of a Novel Microstrip Patch Antenna for Microwave Imaging Systems [2] Dr. K. Meena alias Jeyanthi , E.Thangaselvi , A.S. Prianga, 2013,

Simulation of Rectangular Microstrip Antenna using Nylon Fabric Material

[3] Jigar A soni, Anil K Sisodia,, 2014 Design of Dual band Antenna for Indian Regional Naviagtional Satellites

[4] C.A.Balanis “Antenna Theory : Analysis And Design,3rd_{ Edision, }
John Wiley,2009.

[5] Circular patch antenna design with switchable polarization, 2013, Rahim M.K.A, Yussof M.F.M, Hamid M.R