Planar Rectangular Microstrip Patch Antenna Array with Corporate-Feed Network for Gain Enhancement

Abstract

The design and performance analysis of a inset-fed planar rectangular microstrip patch antenna array with corporate-feed network systems is presented in this paper. This design aims to increase the gain of the rectangular patch antenna through the use of a 16-element planar rectangular antenna array. Each element in this planar array is fed by T-junction power divider networks with quarter-wave transformer lines via the corporate-feed method. The antenna is designed over the operating frequency of 2.4 GHz using the substrate material FR-4, which has a dielectric constant of 4.4 and a loss tangent of 0.002. By the addition of radiating patches in the array design, the gain, directivity and bandwidth also has been improved significantly. The proposed antenna array provides a gain of 9.284 dB, a directivity of 16.2 dBi, and a bandwidth of 0.361 GHz. The designed antenna can be used for wireless applications.

Introduction

I. INTRODUCTION

Antennas are a vital component of modern wireless communication systems. Microstrip patch antennas have become very popular in recent years due to their light weight, low cost, low profile and ease of fabrication using printed circuit technology. Despite numerous advantages, the major limitations of microstrip antennas are their narrow bandwidth and low gain [1]. The microstrip antenna's gain and bandwidth can be enhanced in a variety of ways, such as by increasing its thickness, lowering the substrate's dielectric constant and implementing numerous feeding methods. Although they work as single elements, microstrip antennas are also regularly employed in arrays. An array antenna may provide better gain, directivity, and bandwidth than a single patch antenna. In a microstrip antenna array, individual elements are fed via corporate and series-feed techniques. The main limitation of series-feed arrays is their large variation in impedance. The corporate-feed network is used to provide power splits of 2n (i.e. n = 2, 4, 8, 16, etc) [1]. This can be accomplished by using either tapered lines or quarter-wave transformer lines. The corporate-feed is ideal for scanning phased arrays, multibeam arrays or shaped-beam arrays. The main purpose of the study is to design microstrip antenna array for increasing the gain, improving directivity and enhancing bandwidth. In this research work, a single rectangular patch is designed to analyze the performance based on the inset-feeding technique. The single inset-fed rectangular patch is then arranged in a 4x4 planar array with the corporate feeding method to increase the gain, improve directivity and enhance bandwidth [2][3]. For better impedance matching and minimal return loss, the corporate-feed employs a T-junction power divider network with quarter-wave transformer lines [4].

II. ANTENNA DESIGN

Inset-fed single rectangular patch antenna and 4x4 rectangular patch antenna arrays are designed for analysing the improvement of the above performance parameters. The proposed antennas are designed for 2.45 GHz and simulated using CST Microwave Studio Suite 2018 software.

A. Single Rectangular Patch Antenna

The proposed antenna consists of a rectangular radiating patch and a ground plane on both the sides of FR-4 substrate. This radiating patch with a simple microstrip feeding technique will provide high impedance. To match the impedance with the 50 Ω feed line, an inset feed method is adopted in this design.

The microstrip-feed line width, inset gap and recessed distance are properly selected to match the impedance and minimize return loss. This antenna is designed for a resonant frequency of 2.45 GHz. The length and width of the rectangular patch antenna are calculated by the equations (1) and (2) respectively [1][5][7].

The proposed single rectangular patch and 4x4 patch antenna arrays' simulated and measured VSWR and impedance are illustrated in Fig. 7 and Fig. 8. For both the proposed antennas, there is a good matching between the measured and simulated values of these parameters. Simulated and measured results of inset-fed single element rectangular patch and 4x4 planar array antennas are listed in Table 2. This proposed work achieves comparatively high performance characteristics with an array of 16-elements of inset-fed rectangular microstrip patch antenna. Along with the increase in the antenna size due to the addition of radiating patches in the array design, the gain, directivity and bandwidth also has been improved significantly.

TABLE 2
Results of Single Patch Antenna and Antenna Array

IV. ACKNOWLEDGMENT

The authors would like to acknowledge Sri Dharmasthala Manjunatheshwara College (Autonomous), Ujire and Department of PG Studies and Research in Physics for the support and lab facilities. We also acknowledge the Vision Group on Science and Technology (VGST), Government of Karnataka for the funding to establish Microwave Laboratory.

Conclusion

Inset-fed planar rectangular microstrip patch array antenna using corporate feeding technique is presented in this paper. The gain, directivity and bandwidth of the proposed planar antenna have been improved by increasing the number of array elements and feeding these elements through the corporate feed method. The use of quarter wave transformers into the corporate feed power divider network has improved the impedance matching in the proposed planar array antenna. The planar array antenna provides good performance characteristics. The prototypes of all the simulated antennas are fabricated on FR-4 substrate and measured results are in good agreement with those obtained from simulations. These designed antennas are very simple, cost effective and high efficiency for the applications in S-band frequency ranges like WiFi, WLAN and Bluetooth services.

References

[1] Balanis C. A. (1982) Antenna Theory Design and Application. 3rd Edition, John Wiley & Sons, Inc., Hoboken. [2] Mohammad Riyazuddin and J. Ramlal Bharath (2015) Design and Simulation of C-band Mi-crostrip Corporate Feed Array Antenna. IEEE International Conference on Electromagnetic Interference and Compatibility INCEMIC, Visakhapatnam, India, 22-23 July 2015, 182-186. [3] Pratigya Mathur and Mahima Arrawatia (2020) High Gain Series fed Planar Microstrip An-tenna Array using printed L –probe feed. IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, Montreal, Canada, 5-10 July 2020, 589-590. [4] Stanislav Ogurtsov and Slawomir Koziel (2018) On Alternative Approaches to Design of Corporate Feeds for Low-Sidelobe Microstrip Linear Arrays. IEEE Transactions on Antennas and Propagation, 66, 3781 - 3786. [5] B.Sai Sandeep and S. Sreenath Kashyap (2012) Design and Simulation of Microstrip Patch Array Antenna for Wireless Communications at 2.4 GHz. International Journal of Scientific and Engineering Research, 03, 1-5. [6] Siti Nor Hafizah Sa’don at. el. (2019) Analysis of Graphene Antenna Properties for 5G Ap-plications. MDPI Journal of Sensors, 19, 1-19. [7] George Casu, C?t?lin Moraru and Andrei Kovacs (2014) Design and Implementation of Mi-crostrip Patch Antenna Array. IEEE International Conference on Communications (COMM), Romania, 29-31 May 2014.

Copyright

Copyright © 2024 Dr. Sahana K, Ms. Sowmya K. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.