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A Microstrippatch Antenna Sandwiched Between the Substrate Integrated Waveguide and a Substrate for Dual Frequency Band Applications (Shf and Ehf)

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A Microstrippatch Antenna Sandwiched Between the Substrate Integrated Waveguide and a Substrate for Dual Frequency Band Applications (Shf and Ehf) International Journal of Electronics and Communication Engineering and Technology (IJECET) Volume 11, Issue 4, November-December 2020, pp. 1-9. Article ID: IJECET_11_04_001 Available online at http://iaeme.com/Home/issue/IJECET?Volume=11&Issue=4 Journal Impact Factor (2020): 10.3851 (Calculated by GISI) www.jifactor.com ISSN Print: 0976-6464 and ISSN Online: 0976-6472 © IAEME Publication Scope Database Indexed A MICROSTRIPPATCH ANTENNA SANDWICHED BETWEEN THE SUBSTRATE INTEGRATED WAVEGUIDE AND A SUBSTRATE FOR DUAL FREQUENCY BAND APPLICATIONS (SHF AND EHF) Rajathashree N. M. and K.P. Gowd Department of Electronics and communication Engineering, University Visvesvaraya College of Engineering (UVCE), Bangalore University Circle, Bangalore -560001, Karnataka, India ABSTRACT Mobile technologies have changed the way we live in the modern-day society and manage many aspects of our daily affairs. The need for the broadband and dual band frequencies has increased to cope up with the ever-increasing latter-day requirements. This paper proposes and discusses the design and the simulation results of a microstrip patch antenna at both Super high frequency and Extremely high frequency using the substrate integrated waveguide and the relation between the frequencies and bandwidth are observed. The radiating element is the rectangular patch antenna fed by aperture coupled feeding technique. Substrate integrated waveguide antennas take the advantages of both classical metallic waveguide, which includes high gain, high power capacity, low cross polarization, and high selectivity, and that of planar antennas which comprises low profile, light weight, low fabrication cost, conformability to planar or bent surfaces, and easy integration with planar circuits. In this paper an attempt is made to design microstrip antenna at these frequencies using SIW methodology and aperture feeding technique. Keywords: Substrate Integrated Waveguide (SIW), Microstrip antenna, Super high frequency, extremely high frequency, Aperture coupled feed. Cite this Article: Rajathashree N. M and K.P. Gowd, A MicrostripPatch Antenna Sandwiched between the Substrate Integrated Waveguide and a Substrate for Dual Frequency Band Applications (SHF AND EHF), International Journal of Electronics and Communication Engineering and Technology, 11(4), 2020, pp. 1-9. http://iaeme.com/Home/issue/IJECET?Volume=11&Issue=4 http://iaeme.com/Home/journal/IJECET 1 [email protected] A MicrostripPatch Antenna Sandwiched between the Substrate Integrated Waveguide and a Substrate for Dual Frequency Band Applications (SHF AND EHF) 1. INTRODUCTION Massive changes in the antenna technologies and the increased use of mobile data are seen in the last decade. This huge increase in the demand of wireless cellular communication led to the shortage of the available bandwidth with the designed finite frequency antennas. These cellular service providers have a limited range of carrier frequency spectrum to deliver multimedia and other applications for wireless systems [1]. And the need for the broadband and dual band frequencies has increased to cope up with the difficulty of the service provider. An improved and efficient wireless technology and wideband range of the spectrum is necessary to meet the needs of wireless carriers. There is an overcrowded situation present in the sub-3 GHz spectrum and on the other side, the 3 – 300 GHz frequency range is said to be under-utilized. The Super High Frequency (SHF) is the 3-30 GHz range and the 30-300 GHz is the Extremely High Frequency (EHF) range [2]. The 5G systems will likely utilize in or near this underutilized spectrum ranging from 30-300 GHz. Because of the range of working is shifted to higher frequencies like Ka, V, Wands. The antennas designed should also have proper radiation characteristics. In this paper an attempt is made to design microstrip antenna at these frequencies using SIW and aperture feeding technique to improve the constraints. 2. ANTENNA CONFIGURATION METHOGOLOGY The proposed antenna consists of a microstrip patch antenna fed by Substrate integrated waveguide using Aperture coupled feeding technique. Figure1 (a) and (b) shows a typical configuration of the SIW, where the metallic side walls of the conventional rectangular waveguide are replaced by two rows of metallic vias. Obviously, it is rather difficult to model this type of complex periodic guided-wave structure. [3] (a) (b) Figure 1. (a) Typical SIW configuration, (b) Geometry of substrate integrated waveguide & Upper half region of a typical periodic unit And secondly the design of the Microstrip patch antenna, there are several methods to feed an antenna – Microstrip feed, coaxial feed, proximity coupled feed, aperture coupled feed and so on., here in figure 2 patch antenna is designed with aperture coupled feed is shown. Aperture coupled feed is chosen because no connection made to the antenna element while feeding which implies no radiation from the feed network can interfere with the main http://iaeme.com/Home/journal/IJECET 2 [email protected] Rajathashree N. M and K.P. Gowd radiation pattern. The RF energy from the microstrip feed network is coupled through a common aperture on the ground plane to one or more conducting patches which is supported by a layered dielectric carrier. The coupling aperture is usually centred under the patch, leading to lower cross-polarization due to symmetry of the configuration. The amount of coupling from the feed line to the patch is determined by the shape, size and location of the aperture.[4] Figure 2 Designed Structure of aperture coupled patch antenna – Front and back view Now, the substrate integrated waveguide is fed to Microstrip patch antenna by aperture coupled feeding technique [5]. Substrate integrated waveguide needs to be designed for super high frequency and extremely high frequency. Therefore, vias diameter, distance between vias and the substrate is taken for which a/p and p/d causes minimum error (as in the figure1, a is the horizontal distance between vias, p is the vertical distance between vias and d is a diameter of vias). Structure and return loss curve of Substrate Integrated Waveguide is as shown in figure.3. Figure 3 Designed Structure and return loss curve of Substrate Integrated Waveguide Then, the microstrip patch antenna with Substrate Integrated waveguide which is fed by aperture coupled feeding method is made. The designed substrate integrated waveguide for the super high frequency and extremely high frequency is used with patch antenna fed by aperture coupled technique. Geometry of Aperture coupled microstrip patch antenna fed by substrate integrated waveguide to obtain the results at higher frequency is shown in the figure 4. [7] http://iaeme.com/Home/journal/IJECET 3 [email protected] A MicrostripPatch Antenna Sandwiched between the Substrate Integrated Waveguide and a Substrate for Dual Frequency Band Applications (SHF AND EHF) Figure 4. Geometry of Aperture coupled microstrip patch antenna fed by substrate integrated waveguide In addition to the methodologies mentioned i.e., SIW for higher frequencies, Microstrip patch antenna with aperture coupled feed and Aperture coupled microstrip patch antenna fed by substrate integrated waveguide. Figure 5 shows the microstrip patch antenna which is made to operate at extremely high frequency and super high frequency by using the structure has the substrate of permittivity 4.3, placed above the aperture coupled patch antenna fed by substrate integrated waveguide. Thereby, sandwiching the patch between substrate integrated waveguide and a layer of substrate. Admittedly, this structure has dual frequency band and the advantage of extending the constraints of patch antenna at extremely high frequency. Figure 5. Microstrip patch antenna structure sandwiched between SIW and substrate 3. RESULTS AND DISCUSSION As follows the discussion, figure 6. shows the structure and simulated result of substrate integrated waveguide. Substrate integrated waveguide (SIW) which is placed below the rectangular patch is designed with a substrate Arion AD 1000 having permittivity value of 10.2, the diameter of vias d = 0.75mm, horizontal separation between vias a=7.112mm, vertical separation between vias P= 3mm. http://iaeme.com/Home/journal/IJECET 4 [email protected] Rajathashree N. M and K.P. Gowd Figure 6. Structure and simulated result of substrate integrated waveguide The microstrip patch antenna, shown in figure 2 is designed at resonating frequency 1.75GHz using aperture coupled feeding technique and the expected results are found for the aperture length of 18mm, aperture width of 1.8mm, FR-4 which has permittivity value of 4.3 results in a bandwidth of 49.175MHz which can be seen through return loss curve. Radiation pattern and return loss is shown in the figure 7. Figure 7 Radiation pattern and Return loss of aperture coupled patch antenna The substrate integrated waveguide is fed to Microstrip patch antenna by aperture coupled feeding technique which was discussed with figure 4, is designed to operate at 48.506GHz and has a bandwidth of 1.0688 GHz. The simulation results as shown in figure 8, is obtained with the vias diameter d = 0.632mm, horizontal separation between vias a= 11.92mm, vertical separation between vias P= 1.016mm and substrate is Rogers RT5880 which has epsilon 2.2. http://iaeme.com/Home/journal/IJECET 5 [email protected] A MicrostripPatch Antenna Sandwiched between the Substrate Integrated Waveguide and a Substrate for Dual Frequency Band Applications (SHF AND EHF)
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