EFFICIENT ALGORITHM

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					           JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
              ELECTRONICS AND COMMUNICATION ENGINEERING


      DESIGN AND DEVELOPEMENT MINIATURIZED
         PRINTED SLOT ANTENNA FOR C-BAND
                   APPLICATIONS
       1
           HITESH CHAUKIKAR, 2 DR. KIRAN PARMAR, 3 DR. VED VYAS DWIVEDI
 1
     M.Tech. Student, EC Department, L.D.college of Engineering, Ahmedabad, Gujarat,
  2
     Professor, EC Department, L.D.college of Engineering, Ahmedabad, Gujarat, India
             3
               Director, Noble Group of Institutions, Junagadh, Gujarat, India

                               hitesh_chaikikar@yahoo.co.in,
                   krparmar2006@yahoo.co.in,vedvyasdwivediphd@gmail.com
ABSTRACT: This paper presents an optimization design for the rectangular printed antenna with slotted
ground plane for c-band applications. A slot in the ground plane is shown to improve the bandwidth. The aim of
this design is to develop a single antenna that can be used by all the IEEE 802.11 WLAN network standards
collectively known as Wi-Fi. It is required to have a polarization complementary to that of multi-band printed
monopole antennas, to achieve polarization diversity. The proposed antenna has a small size of 38.8 x 51.7
mm². The design is on FR- 4 substrate with dielectric constant of 4.4 and thickness 0.7 mm. Simulation is
performed by using the HFSS software.

Keywords- Micro Strip-Line-Fed Antennas, Bandwidth Enhancement, Printed Slot Antennas.

1.       INTRODUCTION                                     been shown to have a good bandwidth enhancement.
The popularity of wireless communication systems          However, it is not enough for the operating
has increased significantly in the last decade as         bandwidth to cover more wireless communication
evident from applications such as mobile phones and       services. In this paper, a new design of micro strip-
wireless networks. As the demand for these systems        line-fed printed slot antenna with slotted ground
increases, there is a need for advanced antennas and      plane. In this design, The size of the ground plane is
antenna systems with new capabilities and better          same as the substrate size. By choosing proper
performance. A single antenna that can support            dimensions of the ground plane and parasitic strips, it
multiple communication services such as mobile            is seen that more resonant modes operating near the
phone, Wi-Fi WLAN, Bluetooth etc. is an example.          centre frequency of the conventional slot antenna can
Such an antenna would allow a wireless device with        be obtained. With these resonant modes, the proposed
multiple wireless applications to utilise a single        antenna can have similar radiation patterns and the
antenna element to transmit and receive signals. By       same polarization. From the experimental results, the
only having a single antenna element, the space           obtained impedance bandwidth (10 dB return loss) of
required for antennas on the device is reduced            the proposed antenna can operate from 4 to 8 GHz
significantly. There have been designs of antennas        with a centre frequency at around 5.2 GHz.
operating in dual-band in order to accommodate this.      2.       DESIGN CONSIDERATIONS OF PROPOSED
Some examples of these antennas are fractal antenna,      PRINTED SLOT ANTENNA
printed slot antenna, planar monopole, and printed        In this paper, these proposed antennas are fabricated
inverted-F antenna. These antennas are capable in         on a 0.7-mm thick FR-4 substrate with a dielectric
operating in dual to quad bands. Furthermore, Printed     constant of εr = 4.4 and tan δ = 0.002. The slot is
slot antennas are attractive because of their wide        etched on the ground plane of the substrate as a
impedance bandwidths, low cost, planar structures         radiating element. The length L of the slot of the
and easy integration with active devices or MMICs.        antenna 1 is determined to be λg /2 (where λg is the
Thus, great interest in various printed slot antennas     guided wavelength at 5.2 GHz) in order to obtain a
can be seen in the literature. In recent years, some      maximum power at the broadside direction. A micro
micro strip-line-fed printed slot antennas [1]–[4] have   strip-fed line on the bottom plane of the substrate is
been reported because of their favourable impedance       as a probe excitation of the slot antenna to excite the
characteristics. In the reported literature [4], a        slot mode.
printed\slot antenna with a fork-like tuning stub has

ISSN: 0975 – 6779| NOV 10 TO OCT 11 | VOLUME – 01, ISSUE - 02                                         Page 99
         JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
            ELECTRONICS AND COMMUNICATION ENGINEERING

 Fig. 1 shows the geometry of the proposed printed        Table:1         Calculated parameters of Printed Slot
slot antenna for C-Band applications. The antenna is      Antenna
printed on the top portion of the system circuit board      Name              of         the Values( in mm)
of the mobile phone, whose dimensions are selected          Parameters
                                                            Substrate (FR4)
to be 38.8 mm in length and 51.7 mm in width. The                                            ε r = 4.4
selected dimensions are reasonable for general              Substrate length(L)
                                                                                             38.8
mobile phone’s wifi, and in this study the circuit          Substrate width(W)
                                                                                             51.7
board is fabricated using a 0.7-mm-thick FR4                Ground length
                                                                                             38.8
substrate of relative permittivity 4.4 and loss tangent     Ground width
                                                                                             51.7
0.002.The ground plane is on the top of the substrate.      Micro strip offset for antenna-1
                                                                                             7.90
The slot is cut in the ground plane that’s why              Micro strip offset for antenna-2
                                                                                             7.52
improving the band width of the system.                     Micro strip offset for antenna-3
                                                                                             8.32

                                                          Effects of different parameters in the antenna
                                                          structures on antenna bandwidth have been
                                                          examined. By varying these parameters, the
                                                          resonance frequencies of the antenna can be altered
                                                          to meet the required specifications. InTable-1, the
                                                          value of the all parameters is given. The length of the
                                                          L-Shaped Antenna-2 and Antenna-3 are same as the
                                                          Length of the Antenna-1 that is λg /2. At present, the
                                                          communication systems require really high
                                                          performance antennas; side lobe and cross polar
                                                          levels should be reduced in the radiation pattern as
                                                          well as the size of the antenna.
                                                          3. EQUATION FOR GEOMETRY OF THE PRINTED
                                                          SLOT ANTENNA
                                                          The length of linear slot antenna L1 is designed for
                                                          2.44 GHz which referred with wavelength in the
                                                          substrate ¸λg that can be calculated by following:

Fig.1 Geometry of the Printed Slot Antenna                                                                  (1)


                                                                                                            (2)
                                                          Where ε r is the effective dielectric constant,

                                                                                                            (3)
                                                            In this case, λg = 57.69 mm at frequency 5.2 GHz.




Fig. 2 Final HFSS Model of the Printed Slot Antenna




                                                          Fig. 3 Microstrip Feed

ISSN: 0975 – 6779| NOV 10 TO OCT 11 | VOLUME – 01, ISSUE - 02                                         Page 100
         JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
            ELECTRONICS AND COMMUNICATION ENGINEERING

The width of micro strip line is designed for match
impedance with the characteristic impedance of
transmission line 50 ohms which can be calculated by
following




                                                 (4)
where                     and Z0 is characteristic
impedance.
In this case, width of micro strip line: W = 27.945
mm.At designed frequency of 5.2 GHz, the length of
slot antenna L1 = 25.935 (0.37 λg). The width of
linear slot antenna W1 is varied in five values
beginning from 2.5mm to 5mm by step up 0.5 mm,
and Lm1 is adjusted for match impedance. The
simulation results of return loss S11, resonance                 Fig. 5 Radiation Pattern
frequency, frequency range and bandwidth are
tabulated in Table 1. It shows that the changing in
width of slot antenna will affect on the resonance the
same resonance frequency and wider bandwidth.
When the width of slot is increased, the resonance
frequency will decrease and bandwidth is wider.
Therefore, if we increase the width of slot, the length
of slot should be decreased in order to achieve.
3.        MEASUREMENTS AND RESULTS
The simulation of Printed Slot Antenna was obtained
by using HFSS. It integrates simulation,
visualization, solid modelling, and automation in an
easy-to-learn environment where solutions to your
3D EM problems are quickly and accurately
obtained. Simulations show a very small return loss,
lower than -25 dB in the frequency band of 4 GHz to                                                          F
8 GHz as shown in figure 4. The antenna has very          ig. 6 E Gain
low side lobe level, lower than 36 dB as shown in
figure 5. The measured and simulated E patterns,          Figure 7 shown the simulated and measured 3D
return loss, VSWR plot have a good agreement.             Radiation patterns. The colours in the figures show
                                                          the power level and the E mode pattern is as shown in
                                                          figure 6.




                                                          Fig. 7 3D Radiation Patterns
Fig. 4 Return Loss

ISSN: 0975 – 6779| NOV 10 TO OCT 11 | VOLUME – 01, ISSUE - 02                                      Page 101
         JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
            ELECTRONICS AND COMMUNICATION ENGINEERING

                                                          5. REFERENCES
                                                          [1]      Jan and Jia-Wei Su           ” Bandwidth
                                                          Enhancement of a Printed Wide-Slot Antenna With a
                                                          Rotated Slot” IEEE Transactions On Antennas And
                                                          Propagation, Vol. 53, No. 6, June 2005.
                                                          [2]      Yong Cheng*, Wen-jun Lu,Chong-hu
                                                          Cheng” Printed Diversity Antenna for Ultra-
                                                          wideband Applications” College of Electronic
                                                          Science & Engineering, Jiangsu Key Laboratory of
                                                          Wireless Communications, Nanjing University of
                                                          Posts & Telecommunications, Nanjing, Jiangsu,
                                                          China.
                                                          [3]      Kildas p.-s.,” Gaussian beam model for
                                                          aperture controlled and flareangle-controlled
                                                          corrugated horn antenna ”, IEEE Proceedings,
                                                          Vol.135, pt.H, No.4,August 1988

Fig. 8 3D LHCP and RHCP gain




4.       Fig 9 VSWR


4. SUMMERY
The papers discussed the design of printed slot
antennas operating in the 4.2GHz and 5.4GHz bands
to accommodate IEEE 802.11a WLAN standards.
Effects of different parameters in the antenna
structures on antenna bandwidth have been
examined. By varying these parameters, the
resonance frequencies of the antenna can be altered
to meet the required specifications. This multi-band
printed slot antenna appears to be a promising
companion to previous multi-band printed monopole
antennas in providing polarization diversity
A small, planar, dual-band, low-cost, and easy to
manufacture WLAN antenna having UWB
functionality is presented in this report. The WLAN
antenna achieves excellent dual-band operation and
can be built on other types of microwave substrates
as well. It can be positioned at the edge of a PCB of a
notebook computer, or any other wireless equipment.




ISSN: 0975 – 6779| NOV 10 TO OCT 11 | VOLUME – 01, ISSUE - 02                                   Page 102

				
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