282 INTERNATIONAL JOURNAL OF MICROWAVE AND OPTICAL TECHNOLOGY, VOL.11, NO.4, JULY 2016
Inset fed Microstrip Rectangular Patch Antenna with ‘+’ Shaped Slots for Wireless Applications Manjit Kaur, Shashi B. Rana* Dept. of Electronics and Communication Engineering Guru Nanak Dev University, Regional Campus Gurdaspur (Punjab) India *E-mail:
[email protected] Abstract- The design of rectangular microstrip patch antenna with ‘+’ shaped slots using inset line feeding technique has been presented in this paper. The antenna is designed and simulated by using HFSS V13 software. FR4 glass epoxy having dielectric constant 4.4 and thickness 1.6mm is used as a substrate material for the designing of proposed antenna. The different parameters of designed antenna are calculated and analyzed such as return loss, VSWR, gain, radiation pattern and bandwidth. Simulation results show that the proposed antenna works on five different frequency bands. The value of gain is 9.19dB, 3.13dB, 5.86dB, 9.17dB and 7.38dB for 2.96GHz, 4.62GHz, 5.89GHz, 8.55GHz and 9.68GHz frequency bands respectively. It shows that all the values of gain for different frequency bands are at acceptable level. The designed antenna is fabricated and measured using VNA (Vector Network Analyzer). On comparison, it shows that the measured results of fabricated antennas are in good agreement with simulated results. Index Terms- HFSS, VNA, return loss, inset fed
I. INTRODUCTION In the present scenario, microstrip patch antenna are gaining much attention in the multifunctional wireless communication system such as WLAN (Wireless Local Area Network), satellite, mobile, radar and biomedical systems [1]. These systems require an antenna with high gain, large impedance bandwidth and good radiation pattern throughout the entire operating frequency bands [2]. The wireless communication needs antenna having a low profile, light weight, good performance and multi-frequency band
operations [3]. For the requirement of these parameters, the microstrip antennas are used in most of the wireless devices because of their unique features such as low profile, low cost, ease of fabrication, light weight, compact size, ease of installation etc [4]. In today’s wireless communication there is need of compact size antennas, to reduce the antenna size become extremely important. It is also important that while reducing the size of antennas the performance of antenna should be same as the large sized antennas [5]. Reduction in the size and to further different resonant modes of the antenna can be achieved by introducing different types of slots, notches, and stripes within the patch or in the ground plane [6]. These slots help in improving the gain and reduce the resonant frequency of antenna which is called as miniaturization of the antenna. As compared with patch antennas, a slotted patch antenna fed by different feeding techniques has better characteristics including less conductor loss, wide bandwidth and better isolation between feeding network and radiating element. Due to the different resonant frequency bands, the antenna achieves a multiband characteristic which is the desired need of wireless communication system now a day’s [7]. The multiband and wideband characteristics of antennas are preferred to avoid the use of multiple antennas for different operating frequencies. Besides the use of slotted patch antenna the fractal antennas are also used now a day’s to achieve multiband and wideband characteristics. The geometry of fractal antennas is more complex as compared to microstrip slotted patch antennas. Fractal geometry uses the self-similarity and space filling properties in
IJMOT-2016-4-973 © 2016 IAMOT
283 INTERNATIONAL JOURNAL OF MICROWAVE AND OPTICAL TECHNOLOGY, VOL.11, NO.4, JULY 2016
which the similar shape is introduced in the geometry of antenna at varying iterations [8]. Different types of slotted and fractal patch antennas have been designed and analyzed by the researchers in recent years. Effect of different slots in a design of microstrip antenna have been investigated by B. Roy et.al [9], monopole antenna C shape with a wide slot for UWB applications is designed in B. R. Nithya [10], gain and bandwidth optimization of a novel microstrip patch antenna is described in P. P. Chandran et.al [11], a novel ultra wide band antenna with dual band notches for wireless applications have been designed by I. Acharya et.al [12], design of fractal microstrip antenna for wireless application is analyzed by P. M. Jumle et.al [13] and a dual band compact circularly polarized asymmetrical fractal antenna for Bluetooth and wireless application is designed and investigated by R. Choudhary et.al [14]. In this manuscript a rectangular microstrip patch antenna with plus ‘+’ shaped slots for wireless applications is designed and fabricated. The detailed design, measured and simulation results are discussed in this paper. II. ANTENNA DESIGN AND CONFIGURATION
parameters have been taken into consideration before designing the antennas such as resonant frequency of the antenna, length, and width of the patch and thickness of a substrate. The resonant frequency taken in this design is 3.2GHz. FR4 glass epoxy substrate material with relative permittivity 4.4 and thickness 1.6mm is used to design the geometry of proposed antenna. The width of patch (w) has been calculated by the equation as given below: c
w 2 fo
(1)
r 1 2
here 𝑓𝑟 is the selected resonant frequency, 𝜀𝑟 is the relative permittivity of the substrate and ‘c’ is the velocity of light in free space. The effective dielectric constant has been calculated by using equation as given below:
reff
r 1 r 1 2
2
1
h 2 1 12 w
(2)
here h is the thickness of the substrate , 𝜀𝑟 is the relative permittivity of the substrate and ‘w’ is the width of patch calculated as 28.52mm. The effective dielectric constant must lie in the range of 1
