ANTENNAS AND PROPAGATION 1

The CPW Fed Bowtie Antenna for 8 GHzEdison BorjaCristian Jacho

Marilyn CarrionKateryne Niama

Washington SantosElectronic Engineering in Telecommunications and Network

Abstract—This paper show the design of Bowtie Antenna withessential characteristics coupled to a waveguide with the workfrequency of 8 GHz and a lumped port excitation will be usedfor the CPW fed. Using Ansoft HFSS software v13.0, programwhich will help us better understand how this type of antenna.

Index Terms—Bowtie antenna, CPW, microstrip patch andlumped port.

I. INTRODUCTION

SEVERAL geometric parameters of the antenna were var-ied to observe the impedance matching between the CPW-

feed and the antenna. The inductively coupled CPW feedingmechanism makes the concept suitable for array applications.The bandwidth reduction for an inductively coupled straight-dipole slot is overcome by utilizing an inductively coupledbow-tie slot.

The bowtie patch actually is the combination of imaginaryimage of two triangular patches witch are fabricated in a singlesubstrate. Bowtie microstrip antennas have become popular inthe present day communication scenario due to their in naturecompared to rectangular patches.

The Bowtie microstrip antennas have been designed forwireless LAN communication, where the operating frequency8 GHZ. Design of Bowtie microstrip antenna is based ondesign of triangular microstrip antenna.[2]

The Bowtie patch actually is the combination of imaginaryimage of two triangular patches which are fabricated in asingle substrate.

Comparison between the Bowtie and the fractal antennasshows that the bow tie antenna has a wider bandwidth, highergain, lower front-to-back ratio, lower cross-polarization leveland smaller in size.[1].

II. METHOD

A. Microstrip Bowtie

To create the substrate the antenna is necessary obtainguidance measures. HFSS provides a tool for thesecalculations. The measures for width is -17.0 mm andlength is 32,0 mm and create copper cladding with the samemeasures. Note that this distance is obtained only for thefrequency, in this case 8 GHZ.

Part Distance (mm)1 -2.4352 2.3393 0.6

TABLE ILOOP DISTANCE

Fig. 1. Bowtie Antenna

The next step, is connect the loop with other similar loop,therefore, first, prove connecting two loops with a coupler, inthis case, a transmission line.

Through a sweep of the simulation through differentfrequencies, beginning in 6 GHz and ending in 10 GHz,can on obtained the results of antenna about impedances.Showing a interesting results, because after of optimization,has gotten a very good approximation, at 8 GHz, it is theoperating frequency.

ANTENNAS AND PROPAGATION 2

B. Results

Now, other graphic obtained with HFSS is about theparameter S, in the Fig. 2 is showing the result, in this, canbe seen at 8 GHz,can concluded that the antenna is workingat the ideal reflection coefficient.

Fig. 2. Reflection Coefficient Graphic

This diagram, show how irradiate the antenna, all these, ina polar scale. The Fig 3 is explained the Radiation Pattern.Similar to this, Fig.4 is a 3D diagram, is created by thesoftware HFSS, this exposed the Radiation Pattern with acolor scale showing the wave power.

Fig. 3. Radiation Pattern

Fig. 4. 3D Radiation Pattern

III. CONCLUSIONS

Thanks to this work we could better understand theprototypes of bowtie slot antennas fed by CPW-bowtieantenna and performance is simulated with the help ofAnsoft HFSS software v13.0, this is based on the finiteelement method (FEM), adaptive meshing to give unmatchedperformance ie it can calculate parameters such as Sparameters, resonance Frequency and Field, helping us tobetter understand its operation.

For the design of the CPW Fed Bowtie Antenna at a lowerfrequency dimensions of its structure, in this case we use thefrequency of 8GHz, with which we obtubimos bandwidth of1.4GHz are reduced.

REFERENCES

[1] Web Page. http : //onlinewww.jpier.org/PIER/pier100/08.09102903.pdf/[2] Web Page. http : //www.sciencedirect.com/science/article/pii/S1434/[3] Web Page. http : //ieeexplore.ieee.org/xpl/[4] Web Page. http : //www.antenna −

theory.com/antennas/wideband/bowtie.php[5] Web Page. http : //www.ijmot.com/ijmot/uploaded/1015596486.pdf