DESIGN AND ENHANCEMENT OF

BANDWIDTH MICROSTRIP ANTENNA USING

TRAPEZOIDAL SLOT TECHNIQUE

Taif Alawsi

AIM OF THE PROJECTIs to design a bandwidth-enhanced microstrip antenna.

The design is based on loading one trapezoidal slot with different dimensions into the patch of antenna.

INTRODUCTION

Microstrip patch antennas has several drawbacks including low efficiency and narrow bandwidth ranging from (3-6%) of the central frequency.

Its bandwidth is limited to a few percent which is incapable of meeting the requirements for most of the wireless communication systems nowadays.

In this project one of the most efficient methods was used for the enhancement of the microstrip patch antenna bandwidth which is the loading of microstrip patch antenna with a trapezoidal slot.

Figure 1

ANALYSIS AND MODELING OF RMPATransmission line model is the simplest model and

it gives good physical insight but it is less accurate. The MSA is represented by two slots of width (w)

and height (h) separated by transmission line of length (L). The width of the patch can be calculated from:

BANDWIDTH ENHANCEMENT TECHNIQUEAs was shown in figure 1 , Larger bandwidth can

be made by loading slots within the patch of the antenna with different shapes, arrangements and sizes.

The effect of this techniques on increasing the bandwidth is clearer than using the other techniques.

A dielectric substrate of 𝜀r = 4.3, with loss tangent tan(δ) = 0.019 has been used, the substrate thickness (h) = 5.8 mm, and mesh cells = 314, 608, by using single trapezoidal slot with dimensions (L 𝑔 X 𝑊𝑔) (61.64 mm X 72.8 mm).

RESULTS OF THE SIMULATION SOFTWARE

A

B

Comparison shows that the MSA with single trapezoidal slot has bandwidth of 287.2 MHZ , while without using the slot the bandwidth is 177.2 MHZ

This means that the proposed design enlarged the bandwidth by 110MHZ

Parameters Designed rectangular

patch antenna

Rectangular patch antennawith single trapezoidal slot

 Frequency (GHZ)

 2.421  2.407

( dB) - 42.295 - 45.67

 Gain (dB)  5.95  6.11

 Bandwidth (MHZ)

 177.2  287.2

 BW%  7.31%  11.93%

 Input impedance

(Ohm) 

( 50 +j 0.46) ( 50 +j0.023)

Results comparison between the designed antenna with and without

the slot

CONCLUSION

The rectangular patch Antenna with 50 ohm coaxial feed has been designed.

The enhancement was large about 110 MHZ of bandwidth enlarge, this means that the technique is very effective and shows the differences with a bit care of the design parameters.

FUTURE WORK Examining the effect of the ground plane dimensions on the performance of the antenna element.

The miniaturization of the designed antennas without loss of its efficiency.

Studying the effect of using other feeding methods on the MSA multiband performance.

THANK YOU