China
Africa
Explore chapters and articles related to this topic
Importance and Uses of Microstrip Antenna in IoT
Published in Praveen Kumar Malik, Planar Antennas, 2021
Introduction and Design: For designing patch antenna a icosidodecahedron shaped patch is made. This unique shape results in seven frequency band under UHF and SHF frequency bands. The material used for substrate is FR4, which has dielectric constant of 4.4 and loss tangent taken as 0.02. As we know various benefits of choosing microstrip feedline such as inexpensive to manufacture, easy to fabricate, has polarization diversity, light weight, and good radiation pattern. The planar projection of icosidodecahedron model is introduced as this shape has the largest peripheral length as compared to other simple polygons. Using this shape, the surface current circulation will be boosted, and this will lead to multiband response of antenna [13] (Figure 11.8).
Circularly Polarized Printed Antennas
Published in Binod Kumar Kanaujia, Surendra Kumar Gupta, Jugul Kishor, Deepak Gangwar, Printed Antennas, 2020
Ganga Prasad Pandey, Dinesh Kumar Singh
Microstrip antennas are frequently used in many wireless communication systems because of their attractive features such as planar profile, low cost, lightweight, and easy fabrication [1]. However, the types of applications of microstrip antennas are restricted by their narrow bandwidth. Accordingly, increasing the bandwidth of microstrip antennas has been a primary goal of research in the field. In fact, many broadband microstrip antenna configurations have been reported in last few decades, such as increasing the substrate thickness and decreasing its dielectric constant [2], and using appropriate feeding techniques and impedance matching method [3]. One of the popular methods to improve the bandwidth of a microstrip antenna is to create various resonant structures into one antenna by cutting slots of different shapes, such as U-shaped slot [4] and V-shape slot [5], and by adding more patches [6]. These broadband methods cause some resonance frequencies to appear near the main patch and lead to the bandwidth broadening of the antenna. A capacitive-coupled probe-fed microstrip antenna with wideband characteristics was reported in [7].
Planar Transmission Lines
Published in S. Raghavan, ®, 2019
A cross-sectional view of a microstripline is shown in Figure 2.5. It consists of a dielectric substrate with a strip conductor on one side and the ground plane on the opposite side. Unlike the stripline, the microstrip is basically an open structure and requires high dielectric constant substrates to confine the electromagnetic fields near the strip conductor. Moreover, the microstripline is an inhomogeneous structure. Due to the composite nature of the dielectric interface, propagation cannot be true TEM, that is, a pure TEM mode cannot exist. It is not possible to satisfy the boundary conditions for this mode at the surface of the dielectric. However, at low frequencies, the mode of propagation closely resembles the TEM mode, and hence, is termed the quasi-TEM mode. The electric and magnetic field lines are concentrated predominantly in the dielectric substrate beneath the strip conductor and are somewhat less in the air region above.
Design of circularly polarized antenna using inclined fractal defected ground structure for S-band applications
Published in Electromagnetics, 2020
Sonal Gupta, Binod Kumar Kanaujia, Chhaya Dalela, Shilpee Patil
Microstrip antennas are commonly used in satellite and mobile applications because of its light weight, compact size, less expensive, and easy to be fabricated. Fractal shaped antennas show some attractive features that stalk from their geometrical properties. An overview of fractal shape antennas have been discussed in (Werner and Ganguly 2003), it shows the fractals have no characteristics size, and it consist of many copies of themselves at different scales. Fractal monopole antenna using sierpinski fractal shape has been achieved dual band For LTE applications (Lizzi and Massa 2011). Lots of fractal-shaped structures have been proposed for multi-band antennas (Bayatmaku et al. 2011; Kumar and Nath 2018; Reha et al. 2015). E-shaped fractal patch antenna is used to obtain size reduction and increase the number of operating band for mobile communication applications is reported in (Bayatmaku et al. 2011). H-tree fractal antenna using CPW feed for WLAN, WIMAX, RFID, C-band, Hiper LAN, and UWB applications in (Reha et al. 2015). Different fractal shapes are discussed in (Kumar and Nath 2018).
A reconfigurable high Q epsilon near zero tunnel for material characterization
Published in Journal of Microwave Power and Electromagnetic Energy, 2018
Rosario Peñaloza-Delgado, Tejinder Kaur Kataria, José Roberto Reyes-Ayona, José Luis Olvera-Cervantes, Alonso Corona-Chávez
The liquid samples used in this study were purchased at a local supermarket and are: distilled agave (Kataria et al. 2017), Natural soy milk (Kataria et al. 2018), chocolate soy milk (Kataria et al. 2018) and Chlorine (INDUSTRIAS JLC S.A 2013). These samples were chosen due to their local availability and known dielectric properties. For calibration, distilled water and distilled agave were used. The tunnel was fabricated by pasting two Rogers Duroid 5880 substrates with thicknesses of 0.381 mm and 3.175 mm. The outer walls were made with metallic tape. In this way, the thin discontinuity necessary to couple the tunnel has a thickness of 0.381 mm. For the reconfiguration switches, Gallistan was pumped through the holes using syringes. The microstrip lines were fabricated using conventional photolithography. Measurements were performed using a FieldFox Microwave Analyzer model N9918a (Keysight Technologies, n.d.). Figure 3 shows a picture of the final circuit.
Research on a wide-beam-layered printed antenna for aerocraft telemetry system
Published in Electromagnetics, 2019
Mingxi Zhang, Xiuwen Tian, Xiaochun Liu, Lizhong Song
Microstrip antenna has many advantages, such as easy processing, small size, light weight, simple manufacturing process, easy to realize conformal, and so on. But, the beamwidth of microstrip antenna is generally very narrow (Carver Keith and Jajnesw 1981; Ta and Ziolkowski 2012). However, in order to capture as many satellite signals as possible and obtain the best positioning effect, the terminal antenna is often required to have a broad beam pattern that can cover the upper half of the space. Therefore, in-depth study of wide-beam microstrip antenna has great theoretical value and application value. In recent years, scholars in various countries have done a lot of research on antenna with wide beam. A double-layer patch antenna is used as the radiating element to increase the gain and widen the bandwidth (Zheng, Cheng, and Li 2016). Wide beam can be obtained by excitation of high-order mode or reflector, or microstrip dielectric antenna (Haidan 2002; Wen-hui and Qi 2008). Literature (Zhang et al. 2017) adapt split ring resonators wide-band frequency selective surface (FSS) to obtain widebeam and wideband. In the work by Toko America Inc. (1997), short-range doppler sensors have been applied to achieve a wide-beam performance. A new shaped reflector antenna for wide-beam azimuthal patterns was proposed by Karimkashi, Mallahzadeh, and Rashed-Mohassel (2006). A novel periodic leaky-wave antenna with wide-beam scanning angle is proposed by using miniaturized composite right/left-handed transmission line(Wang et al. 2016). The NRI lens antenna using dielectric resonators for wide angle beam scanning is presented (Kamada, Michishita, and Yamada 2010). In the work by Wen, Wang, and Ding, a microstrip electric dipole and a cavity-backed slot were used to obtain circular polarized wide-beam antenna. This circular polarized wide-beam antenna will be widely used in the wireless communication systems in the future. However, linear polarized antenna has also specific application systems, such as the missile telemetry system. At present, there are also many solutions to broaden antenna beamwidth in practical engineering, such as using the material with high permittivity, adding cavity, or shielding plane behind antenna, or using absorbing materials, or decreasing the ground size, or operating at higher order modes, or matching multi-resonators, or adding parasitic patch, or etching U-slot in patch, or band gap structures, or stacked electromagnetically coupled and aperture-coupled patches, and so on (He, 2002; Kandasamy, Majumder, and Mukherjee et al. 2015; Rowe and Waterhouse 2003; Targonski and Pozar 1998; Yarovoy 2004). The half-power beamwidth of this antenna can be up to 187°, but the half-power beamwidth of this antenna is 34° in E-plane. Literature (Zou, Tong, and He et al. 2017) presented a half-mode SIW edge-radiating slot antenna based on SIW technology. The 3 dB beamwidths of E-plane and H-plane have a large gap, respectively, 44° and 158°. In the work by Duan, Qu, and Wu et al. (2009), microstrip antennas are loaded with gaps and stubs to achieve wideband and broad beam. The 3 dB beamwidth of E-plane and H-plane is about ±60° (Pan, Lin, and Chu 2014).