Design of L/X‐band shared aperture antenna array for SAR application

Further, the designed SRR is placed near to the radiating element. Due to the strong inductive coupling between the monopole and SRR, another lower frequency band apart from the fundamental resonance is obtained. Because of subwavelength resonant characteristics of electric field-coupled SRR, a lower resonance comparatively much less than its size is obtained. Thus, SRR resonance has led to miniaturization. The designed frequency of SRR is shifted slightly due to the coupling effect. To optimize the resonance toward 3.5 GHz, the stubs L5 are added in the SRR. The stubs increase the electrical length of SRR, which in turn lowers the resonance to 3.5 GHz having a reflection coefficient less than 210 dB in the range 3.43– 3.55 GHz. The simulated and measured reflection characteristics of antenna #3 are shown in Figure 4. Measured results indicate that the proposed monopole antenna with metaresonator has a narrow band from 3.48 to 3.62 GHz and a wideband from 5.1 to 11.12 GHz. It is suitable for IEEE 802.16e (WiMAX), IEEE 802.11a/b/g (WLAN), and UWB applications excluding 3.1– 3.48 GHz and 3.62–5.1 GHz. The corresponding bandwidths are about 140 MHz and 6.02 GHz in respective bands. To understand the origin of resonant modes, the surface current distributions are analyzed. From Figure 8, for 3.5 GHz, a dense current distribution is observed around the designed SRR and for the upper bands, it is around the periphery of the monopole. The measured radiation patterns on the y-z plane (Eplane) and x-z plane (H-plane) for 3.55, 5.95, and 9.55 GHz are shown in Figure 9(a)–9(b). It is observed that the SRR radiation in the E-plane is shifted by 908 due to the coupled excitation by monopole. Almost omnidirectional radiation is observed in the H-plane for all the frequency bands. 4. CONCLUSION

A compact electrically coupled SRR-loaded rectangular monopole antenna is presented for multiband WiMAX, WLAN, and UWB applications. The SRR is used to obtain the WiMAX frequency band. The SRR characteristics are discussed in detail. From the measured results, it is observed that, the proposed antenna has sufficient bandwidth in the operating bands to meet the requirements of WLAN/WiMAX/UWB applications. In addition, the proposed antenna has a very compact size compared with the existing WiMAX/WLAN antennas. ACKNOWLEDGMENTS

The authors would like to express their sincere gratitude to Dr. D. C. Pande, Outstanding Scientist, Electronics and Radar Development Establishment (LRDE), DRDO Lab-Bangalore, India for providing the testing facilities to measure the antenna characteristics. REFERENCES 1. V. Rajeshkumar and S. Raghavan, A compact metamaterial inspired triple band antenna for reconfigurable WLAN/WiMAX applications, AEU Int J Electron Commun 69 (2015), 274–280. 2. V.P. Sarin, K.R. Rohith, P.V. Vinesh, R. Dinesh, P. Mohanan, and K. Vasudevan, A metaresonator inspired dual band antenna for wireless applications, IEEE Trans Antennas Propag 62 (2014), 2287– 2291. 3. V. Rajeshkumar and S. Raghavan, Trapezoidal ring quad-band fractal antenna for WLAN/WIMAX applications, Microwave Opt Technol Lett 56 (2014), 2545–2548. 4. M. Ojaroudi and N. Ghadimi, Reconfigurable band-notched small square slot antenna with enhanced bandwidth for octave-band multiresonance applications, Microwave Opt Technol Lett 56 (2014), 1960–1965.

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5. L. Kang, H. Wang, X.H. Wang, and X. Shi, Compact ACS-fed monopole antenna with rectangular SRRs for tri-band operation, Electron Lett 50 (2014), 1112–1114. 6. J.H. Yoon and Y.J. Yoon, Miniaturisation of artificial magnetic conductors using split ring resonator loading, Electron Lett 48 (2012), 439–440. 7. A. Mehdipour, T.A. Denidni, and A.-R. Sebak, Multi-band miniaturised antenna loaded by ZOR and CSRR metamaterial structures with monopolar radiation pattern, IEEE Trans Antennas Propag 62 (2014), 555–562. 8. H. Odabasi and F.L. Teixeira, Electric-field-coupled resonators as metamaterial loadings for waveguide miniaturization, Appl Phys Lett 114 (2013), 214901–214905. 9. R. Bojanic, V. Milosevic, B. Jokanovic, F.M. Mena, and F. Mesa, Enhanced modelling of split-ring resonators couplings in printed circuits, IEEE Trans Microwave Theory Tech 62 (2014), 1605–1615. 10. Ansoft’s High Frequency Structure Simulation (HFSS), Ver. 15, Ansoft Corporation, Pittsburgh, PA, 2013. 11. D.R. Smith, S. Schultz, P. Markos, and C.M. Soukoulis, Determination of negative permittivity and permeability of metamaterials from reflection and transmission coefficients, Phys Rev B 65 (2002), 195104–195109. C 2015 Wiley Periodicals, Inc. V

DESIGN OF L/X-BAND SHARED APERTURE ANTENNA ARRAY FOR SAR APPLICATION Zhou Shi-Gang,1,2 Yang Jiang-Jun,1 and Chio Tan-Huat2 1 Key Laboratory of Space Electronic Information Perception and Photoelectric Control, Northwestern Polytechnical University, 710129 Xi’an, People’s Republic of China 2 Temasek Laboratories, National University of Singapore, 5A Engineering Drive 1, 117411, Singapore; Corresponding author: [email protected] Received 6 February 2015 ABSTRACT: Design of a dual-wideband dual-polarized planar shared aperture microstrip antenna array is proposed in this article. Differential feeding method is used to enhance the isolation between polarizations of the antenna in both bands.Corporate feed network is used for good radiation pattern results. Further, the coupling between the feed networks the two orthogonal polarizations is minimized. This is achieved using the antenna elements to separate the feed networks for orthogonal polarizations. To verify the antenna design, a prototype is fabricated and measured. For VSWR, the antenna can cover from 1.07 to 1.24 GHz (14.7%) and from 8.3 to10.3 GHz (21.5%), respectively. The measured isolation between bands is higher than 30 dB and the isolation between polarizations is higher than 22.5 and 29.6 dB in L- and X-band, respecC 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett tively. V 57:2197–2204, 2015; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.29291 Key words: wideband antenna; microstrip antenna; dual-band dualpolarized antenna 1. INTRODUCTION

Dual-band dual-polarized (DBDP) antennas can improve the synthetic aperture radars (SAR) [1] performance by providing frequency and polarization diversity. The interleaved layout is one of the more common configurations to allow the DBDP antennas sharing the same aperture, which in turn reduce the size and weight of the antenna. Among all the shared aperture antenna (SAA) arrays, microstrip antenna is often the preferred choice for DBDP SAAs design. A SAA in the L- and C-band

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Figure 1 Geometry of the proposed antenna. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com]

using of slots for L-band and microstrip patches for C-band is proposed by Poluls et al. in [2]. An L/X-band and an L/C-band using perforated patches and patches are presented in [3,4], respectively. Another SAA design using aperture-coupled patches with good cross-polarization performance is presented in [5]. References 6,7 provided another SAA technique using interleaving dipoles and microstrip patches. We also presented a P/ Ku-bands SAA in [8] using higher frequency band array on the lower frequency band antenna patch, which is suitable for the SAA with large frequency ratio. For the microstrip SAAs, the main disadvantage may be the narrow bandwidth, especially when the frequency ratio between the higher and lower frequency is large. This is because the restricted space between the elements in the high-frequency band will lead to a high-Q resonant cavity mode and very narrow bandwidth in the lower frequency band. Using the ground separating the feed networks for low and high bands to improve the isolation between bands is a good design [4], which means that the feed networks for orthogonal polarizations in the same band have to be placed on the same side of the ground. The space is very limited when the feed networks for the two orthogonal polarizations are placed on the same layer. Thus, the series feed network, which takes up less space is usually selected especially in the high-frequency band. However, the series feed network typically result in narrow pattern bandwidth due to frequency squinting. Previously, we had designed a SAA using stacked patches as the radiation elements and combined using corporate feed networks for both bands to widen the bandwidth in [9]. We then made improvements to achieve better performance, especially impedance and pattern bandwidth,

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which also published as a conference paper but without measured results and details of design [10]. In this article, a shared aperture microstrip antenna operating in L/X-bands for SAR applications is designed and investigated. The primary objectives of this work were to develop technologies to widen the bandwidth of the SAA while maintaining good radiation pattern performances over the whole band. The design details and tradeoff between VSWR bandwidth, isolation, and cross-polarization performances are presented in the following sections.

2. ANTENNA ARRAY CONFIGURATIONS AND DESIGN

Figure 1 gives the configuration of the antenna, which shows that the perforated patches are selected for the L-band and conventional patches are chosen for the X-band. Proximity-coupled and aperture-coupled feed are selected for L/X-band, respectively. Such feed designs meant that vertical connections are not needed, aiding convenience during fabrication. To increase the bandwidth of the array, stacked patch is used in both the L/Xband. As shown in Figure 1, four-layer PCB substrates are used in this SAA design. Starting from the bottom of the structure, the first layer is 0.381-mm thick, which is used for the ground with slots on the top and feeding networks for X-band on the bottom. The last three layers are 0.787-mm thick. The L-band feeding network on and the X-band driven patches are on the second layer, the L-band driven patch and X-band parasitic patch are on the third layer and the fourth layer is used for the L-band parasitic patch. Plastic strips on the edge are used to separate the substrate layers, which can also provide the

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Figure 3 Top view of the X-band antenna element TABLE 2 The Dimensions of X-band Antenna Element Figure 2 Top view of the L-band antenna element

Symbol

necessary air gaps between adjacent layers. We also make a metal chassis packaging the antenna. The size of the antenna is 240 3 240 3 27 mm3. As mentioned above, the perforated stacked patch is used for the L-band antenna design. Figure 2 gives the configuration of the L-band patch antenna. The configuration of the L-band antenna is similar with that in [9]. The improvement is that: The feed lines for vertical polarization are combined by a 1808 differential power divider, which improves the isolation between the two ports of the orthogonal polarizations. The primary optimized dimensions of the proposed antenna and feed lines are listed in Table 1. The basic configuration of the X-band array is also the same as that in [9]. Figure 3 shows the top view and parameters of the X-band patch antenna. H-shaped slot at the center is used for the vertical polarization and slots with bends at the ends and

Xpl1 Xpl2 Xhsl Xvsl Xhl1 Xhl2

Size (mm) 7.9 10.1 9.5 5.9 5.8 1.8

Symbol Xhl3 Xhw1 Xvl1 Xvl2 Xvw1

Size (mm) 11.7 1.8 2.6 1.4 6

TABLE 1 The Dimensions of L-band Antenna Symbol Lpl1 Lpl2 Lp1 Lp2 Lhl1 Lhl2 Lhw1

Size (mm) 93.7 99 13.4 18 25 16 1.98

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Symbol Lvl1 Lvl2 Lvw1 Lvw2 h1 h2 h3

Size (mm) 29.1 13.3 1 6 4 6 6

Figure 4 Layout of the 2 3 2 subarray

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Figure 5 Feed network layout for X-band array (a) the entire feed network and (b) the subarray feed networks

Figure 6 Photo of the proposed antenna. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com]

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Figure 7 (SAA)

Measured VSWR results of the L/X shared aperture antenna

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Figure 8 Measured Isolation results of the L/X SAA. (a) Isolation between polarizations and (b) isolation between bands

Figure 9 Measured radiation L-band patterns of the L/X-band shared aperture array. (a) H-pol, 1.07 GHz, (b) V-pol, 1.07 GHz, (c) H-pol, 1.24 GHz, and (d) V-pol, 1.24 GHz

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Figure 10 Measured radiation X-band patterns of the L/X-band shared aperture array. (a) H-pol, 8.6 GHz, (b) V-pol, 8.6 GHz, (c) H-pol, 10.3 GHz, and (d) V-pol, 10.3 GHz

located at the edge are used for horizontal polarization. The differential feeding for horizontal polarization is also adopted to improve the isolation. Such differential feed also has the

Figure 11 Measured realized gain of the antenna

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advantage of achieving more symmetrical radiation patterns. Here, the ports of the antenna elements for horizontal port and vertical port are matched to 50 and 100 X, respectively. The primary dimensions of the X-band element are listed in Table 2. The power combining architecture is illustrated by considering a 2 3 2 subarray as shown in Figure 4. To reduce the space needed between adjacent elements in a row, feed networks are used to connect the two ports of the “left and right” adjacent elements. To improve the isolation between the horizontal and vertical polarization ports, the feed network for one polarization would be placed in the space between two rows of radiating elements. This meant that a row of radiating elements separates the feed networks of the horizontal and vertical polarizations. However, this arrangement mentioned requires that the elements for vertical polarizations in the “upper” and “lower” adjacent rows must be excited out-of-phase. Similarly, the elements for horizontal polarizations in “right and left” adjacent columns need to be excited out-of-phase as well. In such a manner, the “pairwise antiphase fed” style can be produced, and this helps to improve the isolation and cross-polarization performance [11].

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TABLE 3 The Details of the Pattern Results

Polarization H-pol

V-pol

V-pol

H-pol

Cross-pol Level (dB)

Frequency (GHz)

E-plane

H-plane

1.07 1.15 1.24 1.07 1.15 1.24 8.3 8.6 9.5 10.3 8.3 8.6 9.5 10.3

217.0 218.1 223.2 217.0 220.6 217.9 222.5 224.6 230.3 224.2 223.7 230.8 235.4 229.2

217.6 217.9 218.9 217.5 219.5 217.0 219.6 223.6 230.3 221.8 220.0 230.4 230.3 225.4

Realized Gain (dB) 6.9 6.9 6.0 6.8 7.0 5.8 21.0 21.4 23.0 20.5 17.9 20.1 22.9 20.4

After the development of the subarrays, the whole planar array was constructed. The overall feed network layout of the X-band planar array is given in Figure 5. The whole feed network includes three kinds of feed networks. The first is a oneto-eight feed network connecting 2 3 2 subarrays to an 8 3 2 subarray for both horizontal and vertical polarizations. The second is a one-to-four feed network connecting 8 3 2 subarrays to an 8 3 8 planar array for vertical polarization. The third one is also one-to-four feed network used to connect 2 3 1 subarrays to an 8 3 1 subarray for horizontal polarization. The fourth one is a one-to-five feed network connecting three 8 3 2 subarrays and two 8 3 1 to an 8 3 8 planar array for horizontal polarization. All the three kinds of feed networks with matching impedance at junctions are shown in Figure 5. As the transmission lines in the feed network are very closely spaced, the coupling between the transmission lines must be considered during the design [12,13]. 3. SIMULATED AND MEASURED RESULTS

We fabricated and measured a prototype of the proposed antenna. As shown in Figure 6, an aluminum plane with the size of 550 3 550 mm2 for measurement is used here. Because of the limitations in computer resources, it is not possible to simulate the combined L/X-band structure. In such cases, only the measurement results of the antenna are given. The measured VSWR at all of the four ports are shown in Figure 7. It can be seen that, the antenna covers the frequency band of 1.07–1.24 and 8.3–10.3 GHz with VSWR below 2.0. Figure 8(a) gives the measured isolation results between orthogonal polarizations results both in L/X-bands. It can be seen that the isolation between polarizations is better than 22.5 dB over the band of 1.07–1.24 GHz (better than 25 dB over most part of the band) and is better than 29.6 dB over the band of 8.3– 10.3 GHz (better than 35 dB over most part of the band). Figure 8(b) gives the measured isolation results between L/X-bands. HH ports refers to L-band horizontal port and X-band horizontal port, HV ports refers to L-band horizontal port and X-band vertical port, VH ports refers to L-band vertical port and X-band horizontal port and VV ports refers to L-band vertical port and X-band vertical port. From the measured results, we can see the worst-case isolation between bands is 40 dB in L-band and 30 dB in X-band.

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Radiation patterns are measured in the chamber in far field range. The normalized patterns at point of 1.07 and 1.24 GHz for L-band are presented in Figure 9. It can be seen that the cross-polarization is best at the low end of the operating band, being 217 dB. The normalized patterns at the frequency point of 8.6 and 10.3 GHz are shown in Figure 10. The sidelobes of patterns below 8.6 GHz is higher than 210 dB, which is because the feeding is not ideal differential feeding, so the antenna can only be operated from 8.6 to 10.3 GHz. It can be seen that the highest cross-polarization level is 220 dB over the entire frequency band of 8.6–10.3 GHz. The measured realized gain over both the L- and X-frequency bands are presented in Figure 11. The gain varies from 6.0 to 7.8 dB in L-band and from 20.4 to 23.2 dB in X-band (8.6–10.3 GHz), the H-pol gain drops a lot below 8.6 GHz is because the high sidelobe. The details of the measured pattern results are listed in Table 3. 5. CONCLUSION

A SAA for SAR applications is presented in this article. Several techniques are used to achieve wide bandwidth of the SAA. Corporate feed network is chosen in the X-band array to maintain good pattern performance over wide bandwidth band. The feed networks for different polarizations are separated by the elements to achieve good isolation and cross-polarization results. A prototype of this antenna is also fabricated and measured. The measured results show that the bandwidths for the L- and X-band are 14.7 and 21.5%, respectively. The isolation between bands is higher than 30 dB and the isolation between polarizations is higher than 22.5 and 29.6 dB in L/X-band, respectively. The worst crosspolarization results in the L/X-band are 217 and 220 dB. ACKNOWLEDGMENTS

The research is supported by the National Science Foundation (61401356) and Fundamental Research Funds for Central Universities (GEKY8002). REFERENCES 1. R.L. Jordan, B.L. Huneycutt, and M. Werner, The SIR-C/X SAR synthetic aperture radar antennas, IEEE Trans Antennas Propag 33 (1995), 829–839. 2. Z. Zahairs, E. Vafiadis, and J.N. Sahalos, On the design of a dualband base station wire antenna, IEEE Antennas Propag Mag 42 (2000), 144–151. 3. L.L. Shafai, W.A. Chamma, M. Barakat, P.C. Strickland, and G. Seguin, Dual-band dual-polarized perforated microstrip antennas for SAR applications, IEEE Trans Antennas Propag 48 (2000), 58–66. 4. A. Vallecchi and G.B. Gentili, An interlace microstrip patch array antenna for dual-band dual-polarized operation, Available at: http:// www.elettromagnetismo.it/atti_rinem/2004S03A04.pdf. 5. D.M. Pozar and S.D. Targonski, A shared-aperture dual-band dualpolarized microstrip array, IEEE Trans Antennas Propag 49 (2001), 150–157. 6. X. Qu, S.S. Zhong, and Y.M. Zhang, Dual-band dual-polarized microstrip antenna array for SAR applications, Electron Lett 42 (2006), 1376–1377. 7. X. Qu, S.S. Zhong, Y.M. Zhang, and W. Wang, Design of an S/X dual-band dual-polarised microstrip antenna array for SAR applications, IET Microwaves Antennas Propag 1 (2007), 513–517. 8. S.H. Hsu, Y.J. Ren, and K. Chang, A dual-polarized planar-array antenna for s-band and x-band airborne applications, IEEE Antennas Propag Mag 51 (2009), 70–78. 9. S.G. Zhou, P.K. Tan, and T.H. Chio, A wideband, low profile Pand Ku-band shared aperture antenna with high isolation and low cross-polarization, IET Microwaves Antennas Propag 7 (2013), 223– 229.

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10. S.G. Zhou, T.H. Chio, and J. Lu, A shared-aperture dual-wideband dual-polarized stacked microstrip array, Microwave Opt Technol Lett 54 (2012), 486–491. 11. S.G. Zhouand T.H. Chio, Dual-wideband, dual-polarized shared aperture antenna with high isolation and low cross-polarization, In: The 10th International Symposium on Antennas and Propagation, and EM theory, Xi’an, China, 2012. 12. K. Woelder and J. Granhoim, Cross-polarization and sidelobe suppression in dual liner polarization antenna arrays, IEEE Trans Antennas Propag 45 (1997), 1727–1740. 13. 13. S.G. Zhou, T.H. Chio, and J. Lu, Dual linear polarization patch antenna array with high isolation and low cross-polarization, In: IEEE International Symposium on Antennas and Propagation, Spokane, WA, 2011, pp. 588–590. C 2015 Wiley Periodicals, Inc. V

A MICROSTRIP-FED REFORMED RECTANGULAR SHAPE SLOTTED PATCH ANTENNA FOR SIMULTANEOUS OPERATION IN GPS AND WLAN BANDS Md Rezwanul Ahsan,1 Mohammad Tariqul Islam,1 and Mohammad Habib Ullah2 1 Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia; Corresponding author: [email protected] 2 Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia Received 8 February 2015 ABSTRACT: A microstrip-line feed simple design of modified rectangular slotted patch antenna is proposed for dual-frequency operation. The typical rectangular shape of the patch is reformed by integrating slots and extending the radiating patch to some extent for achieving desired resonance. With the optimized dimensions from numerical simulating software, the proposed antenna is printed on 1.905-mm-thick 40 3 40 mm2 ceramic composite substrate with relative dielectric constant er 5 10.2. The experimental results confirm the bandwidths for S11 210 dB are of 780 MHz (1.13–1.91 GHz) and 1.22 GHz (4.83– 6.05 GHz) with resonance frequency 1.48 and 5.61 GHz, respectively. The antenna prototype shows almost consistent and symmetrical radiation patterns with maximum gain of 3.42 and 4.37 dBi for lower and upper frequency band, respectively. On the basis of well-agreed simulated and measured results, adequate bandwidth, stable radiation, and acceptable gain performance make the antenna suitable for serving simultaneously in global positioning system and wireless local area netC 2015 Wiley Periodicals, Inc. Microwave Opt Technol work bands. V Lett 57:2204–2207, 2015; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.29290

[1,2]. The microstrip patch antennas are widely investigated in last few decades due to their planar structure, small form factor, simple geometrical design, and offer less-tedious integration facility with other components of wireless equipment [3,4]. As the high-speed data communication network evolves, the location-based social network utilities become more active part in daily life. For this reason, the compact antennas for global positioning system (GPS) and wireless local area network (WLAN) are vastly integrated to the smart portable communication devices like mobile, tablet, laptop, and so forth [5]. Therefore, the antenna functioning at multiple frequencies is necessarily required to save the room by replacing singlefrequency antennas and simplify the integration system. However, mitigation of inherited shortcomings of patch antenna is certainly a challenging task as it requires to maintain wide bandwidth, acceptable antenna gain, and stable radiation by preserving the compact size and low cost. The outcome of the reviewing recently published literatures provides a number of methods that can be applied to achieve dual-band/multiband operability with reasonable bandwidth and acceptable gain. Some of the dual-band/multiband antennas are reported: slotted monopole antenna [6], cavity backed annular slot antenna [7], high directivity electromagnetic bandgap resonator [8], microstrip antenna on low temperature cofired ceramic multilayer substrate [9], W-slot loaded patch antenna [10], single slotted patch and ground slot antenna [11], and so forth. No matter what, the reported literatures indicate a small number of antennas operating at both GPS and WLAN bands. In addition, the antennas of the intended GPS/WLAN functions have some constrains in terms of volumetric size, design complexity, marginal gain/bandwidth, unstable radiation, and so forth. However, research opportunities are always there to tune up the antenna performances by searching and exploiting different techniques. In this article, a microstrip line feed modified rectangular slotted patch antenna has been presented for serving GPS and WLAN band functionalities. The slots and extended radiating patch are properly positioned and optimized to attain double resonance mode of operation which can cover L1/L2 GPS and 5.2/ 5.8 GHz WLAN frequency bands. Throughout the design processes, the finite element method (FEM)-based electromagnetic field solver high frequency structure synthesizer (HFSS) is used to perform numerical synthesis and optimization. The measured results from physical prototype show two operating bands with bandwidth 52.7% from 1.13 to 1.91 GHz and 21.75% from 4.83 to 6.05 GHz at 1.48 and 5.61 GHz center frequency, respectively.

2. ANTENNA DESIGN Key words: composite materials; dual band; modified rectangle; microstrip feed; patch antenna; global positioning system; wireless local area network 1. INTRODUCTION

The cutting edge technology inspired today’s wireless communication systems have put the focus on the requirement of adequate bandwidth and multiband operability. Furthermore, the antenna as a principal component of wireless devices needs to be of compact size, simple structure, and inexpensive, which requires less effort to fabricate. By complying with the requirements, the researchers from industry and academia have ventured many ways to develop multifunctional antenna having easy integration capability for portable communication devices

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The geometrical structure of the proposed dual band antenna is illustrated in Figure 1. The final design of the antenna with its optimal dimensions is fabricated on ceramic-polytetrafluoroethylene composites material substrate with permittivity of 10.2, loss tangent 0.0023, and substrate thickness is 1.905 mm. The high-frequency laminates substrate material having high dielectric constant is considered for the antenna designing process which gives compact profile for microwave and electronic circuitry applications. The overall size of the antenna is 40 3 40 mm2 with modified slotted rectangular radiating element at the top and partial perfect electric conductor as a ground at the bottom. The antenna’s radiating element is excited through 5.0 mm long and 2.1 mm wide microstrip line which is properly designed to comply with the 50 X characteristic impedance. Various parametric studies are executed with the help

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