Design and Implementation of Microstrip Yagi-Uda Antenna

IJSRD - International Journal for Scientific Research & Development| Vol. 4, Issue 03, 2016 | ISSN (online): 2321-0613

Design and Implementation of Microstrip Yagi-Uda Antenna Mohammad Irfan1 Nithya.B2 Mitu Kumari3 Milind M Deshpande4 P.Rajeswari5 1,2,3,4 Student 5Associate Professor 1,2,3,4,5 Department of Telecommunication Engineering Abstract— Yagi-Uda antenna is a directional antenna which consists of multiple parallel elements in a line. Advantages of using microstrip antennas are low weight, easy to fabricate and low cost. This paper presents a novel design of a microstrip Yagi-Uda antenna operating at 0.9 and 6GHz. The substrate used in this design is Rogers/RT Duroid 5880 (ɛr=2.2). This paper provides a comparative study of YagiUda antenna operating at two different frequencies. The various results such as return loss, VSWR, radiation patterns, gain are realized. The simulation of this structure is done by using Ansoft High Frequency Structural Simulator (HFSS) tool.

Key words: Directional Antenna, Microstrip Yagi-Uda Antenna I. INTRODUCTION Communication is referred to the process of transmitting and receiving the data using electromagnetic waves. In recent trend, wireless communication plays a major role when compared to that of wired. From sender, the information is carried to a receiver over a particular channel or media. Each transmitting channel has got a particular frequency, bandwidth and data rate.

In today’s technology antennas play a major role in wireless communication systems. With the increase in growth of wireless technology there is also increase in demand for low size, high profile microstrip antennas.

Microstrip antennas find its applications in satellites, missiles, military etc.

In 1926, Dr. Shintaro Uda and Dr. Hidetsugu Yagi of Tohoku Imperial University invented a directional antenna system consisting of an array of coupled parallel dipoles. The Yagi antenna consists of a single feed or driven element. This is the only element which is excited. The rest of the elements are parasitic-they either reflect or transmit energy in a particular direction. The element to the left of feed element is called the reflector which is 5% longer than feed element. The elements to the right of feed line are directors and the length of these are 5% lesser than directors.

This antenna finds its applications from short waves to microwave frequencies. Yagi-Uda antennas find its applications in industrial, medical, satellites etc.

mounted on a substrate with a defined thickness. There are different types of substrate with defined dielectric constant.

The length and width of patch varies depending on dielectric constant. As the dielectric constant increases length and width of patch decreases whereas, bandwidth decreases and increases the Q-factor of the patch antenna. Fig 1 shows the basic structure of microstrip antenna. If the thickness of substrate increases, the bandwidth and efficiency also increase, but unfortunately it increases the surface wave of low propagation that causes power loss.

Microstrip patch antennas are excited by various methods in order to make antenna to radiate in free space.

The feeding techniques are classified into two types, namely contacting and non-contacting. Most commonly used feeding techniques are microstrip feed line, co-axial probe feed, aperture coupling feed and proximity coupling feed.

Fig. 1: Basic structure of patch antenna III. MICROSTRIP YAGI-UDA ANTENNA The proposed Yagi-Uda antenna structure is shown in fig2.

The design consists of a reflector, microstrip patch along with microstrip feed line which is a driven element and three directors. The microstrip Yagi-Uda antenna is excited through the driven patch along with a feed line. The length and width of the patch are calculated by using some standard formulas. In the proposed design the length and width of all three directors are same and spacing between all the elements are also equal.

II. MICROSTRIP PATCH ANTENNA Patch or a microstrip antenna is a rectangular, square, circular metal patch on a thin layer of dielectric substrate on a ground plane. Patch antenna is a type of radio antenna.

Patches are photo etched for low-cost mass production.

Patch antennas are widely used for UHF and higher frequencies. Microstrip antennas are inexpensive to design and manufacture. Microstrip patch antennas are implemented in mobile radio communications, aircrafts, satellite communications etc.

The most commonly employed microstrip antenna is rectangular patch. It usually consists of a patch which is

Fig. 2: Proposed microstrip Yagi-Uda antenna The designs are simulated using Ansoft High Frequency Structural Simulator (HFSS) tool. Various antenna parameters are analyzed by adjusting the length, width and spacing between the elements. In case of 0.9GHz frequency, height of the substrate is taken as 3mm and for

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Design and Implementation of Microstrip Yagi-Uda Antenna (IJSRD/Vol. 4/Issue 03/2016/181)

6GHz frequency, height of the substrate is taken as 1.6mm.

It is analyzed from the simulations that gain of the antenna increases as the height of substrate increases. For both the frequencies (0.9 and 6GHz) the characteristic impedance is 50ohms.

IV. DESIGN PARAMETERS In the proposed design, we need to determine the length and width of the microstrip patch by using the available information. The specified information are dielectric constant (ɛr), height of the substrate (h) and frequency of operation (fr).

The width of the driven element is given by,

Fig. 3.2: S11 parameter graph for resonating frequency 6GHz and return loss= -21.2966 dB B. VSWR

The effective dielectric constant is determined by, Determination of extension length (ΔL) using (1) and (2)

The effective length of the patch is given by, Fig. 4.1: VSWR=1.0425 for resonating frequency 0.9GHz Thus the length of microstrip patch element is given as, The calculated values are shown in Table I Driven patch 0.9GHz 6GHz Width(w) 131.7mm 19.75mm Length(L) 110.9mm 15.88mm Table 1: Length and width of patch antenna for 0.9 GHz and6 GHz Element Length Separation Reflector 0.45λ 0.1λ Director 0.3λ 0.1λ Table 2: Length and separation between elements in terms of wavelength

Fig. 4.2: VSWR=1.4997 for resonating frequency 6GHz C. Gain

V. RESULTS Various antenna parameters are simulated using HFSS tool.

The results of microstrip Yagi-Uda antenna operating at two different frequencies are simulated and are compared.

A. S-Parameter

Fig. 5.1: Gain=9.5906 dB for 0.9GHz frequency

Fig. 3.1: S11 parameter graph for resonating frequency 0.9GHz and return loss=-24.4457 dB

Fig. 5.2: Gain=3.9238dB for 6GHz frequency

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Design and Implementation of Microstrip Yagi-Uda Antenna (IJSRD/Vol. 4/Issue 03/2016/181)

D. Radiation Pattern

Fig 6.1 Radiation pattern for 0.9GHz frequency

REFERENCES [1] Hemjith M, Anoop BK, Manoj KC “ A Review on Recent Trends and Developments in the Design and Application of Yagi Uda Antenna” IOSR Journal of Electronics and Communication Engineering (IOSRJECE) e-ISSN:2278-2834, p-ISSN: 2278-8735, Volume 10, Issue 5, Ver.II (Sep-Oct.2015), PP 28-34.

[2] Payal, R. Madhusudan Goud, Komalpreet Kaur “Design of Yagi-Uda Antenna using Microstrip Circuit” International Journal of Computer Applications (09758887) Volume 96-No.24, June-2014.

[3] Kamalakshi Bevur and Dr. T S Rukmini “Design and Development of Microstrip Yagi-Uda Array for 900MHz frequency” Karpagam Journal of Engineering Research (KJER) Volume No. III, ISSN: 2393-994X. [4] Mahesh Kumar Aghwariya “Microstrip Patch Yagi-Uda Array for Millimeter Wave Applications” International Journal of Engineering Research and General Science Volume 2, Issue 4, June-July 2014, ISSN 2091-2730.

[5] Satyandra Singh Lodhi and P.K.Singhal “Microstrip Yagi-Uda Antenna at 2.45GHz for ISM Band Application” International Journal of Research in Engineering and Technology( IJRET) Volume 1, Issue 2, July 2013, 151-154.

Fig 6.2: Radiation pattern for 6GHz frequency Parameters 0.9GHz 6GHz Return Loss -24.4457 dB -21.2966 dB VSWR 1.0425 1.4997 Gain 9.5906 dB 3.9238 dB Directivity 1.8489 dB 5.1557 dB Table 3: Comparison Of The Results Obtained From Microstrip Yagi-Uda Antenna AT 0.9GHz and 6 GHz Frequency VI. FUTURE WORK The antenna size can be reduced by increasing the frequency of operation and dielectric constant of the substrate. The performance of antenna can be further improved by varying the antenna parameters. The work can be extended to microwave components.

VII. CONCLUSION This paper describes the design and implementation of Microstrip Yagi-Uda antenna for 0.9GHz and 6GHz. The 3D structure of the antenna is simulated using Ansoft HFSS tool. The antenna parameters such as gain, VSWR, return loss and radiation pattern are simulated and results are compared. However, the gain of the Yagi antenna at 0.9 GHz is higher than the gain obtained at 6 GHz. These antennas can be implemented for various ground station applications.

ACKNOWLEDGMENT The authors would like to thank Mrs. P.Rajeswari, Associate Professor, TCE, DSCE for her continuous support in completing this work. The authors further extend their gratitude towards Mr. C.Jayanth and Mrs. Pushpa.B.R for the guidance throughout this work.

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