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Importance and Uses of Microstrip Antenna in IoT
Published in Praveen Kumar Malik, Planar Antennas, 2021
The microstrip patches can be rectangular, square, triangular, etc. When the width and length of antenna is reduced, the antenna gets miniaturized and resonant frequency also goes higher. The substrate material plays an important role in designing aspect, and a larger substrate will result in large bandwidth desired for IoT devices. Thus for substrate FR4 is used that has dielectric constant of 4.4. The height of substrate of 1.6 mm and 0.002 values is chosen for loss tangent. Microstrip strip feed line is used as feeding technique as it has easy fabrication, good radiation by feed, and good matching of impedance. Let us discuss the designing process by finding the values of dimension of antenna patch, feedline, and effective constant [9].
Electromagnetics and Transmission Lines for Wearable Communication Systems
Published in Albert Sabban, Wearable Systems and Antennas Technologies for 5G, IOT and Medical Systems, 2020
In Table 2.11, soft materials are presented. Duroid is the most popular soft substrate in MICs and in the printed antennas industry. Dielectric losses in Duroid are significantly lower than dielectric losses in FR-4 substrate. However, the cost of FR-4 substrate is significantly lower than the cost of Duroid. FR-4 is the most common material that is used in fabricated circuit boards. “FR” indicates the material is flame retardant and the “4” indicates woven glass reinforced epoxy resin. Commercial MIC devices usually use FR-4 substrate. Duroid is the most popular soft substrate used in the development of printed antennas with high efficiency at microwave frequencies.
Multiband Four Port Mimo Antenna Using Metamaterials
Published in T. Kishore Kumar, Ravi Kumar Jatoth, V. V. Mani, Electronics and Communications Engineering, 2019
F. B. Shiddanagouda, R. M. Vani, P. V. Hunagund, Siva Kumara Swamy
The substrate is FR4 with dielectric constant equal to 4.4. Dielectric dimensions Ls × Ws are 10 mm × 10 mm and the thickness t is 1.6 mm. The strip width of each octagon is 0.6 mm. The sides of the octagons from the outer side to the inner side (S1, S2, S3, S4) are 4.0, 3.5, 2.8, and 2.3 mm, respectively. Both of the gaps, g, in the octagons are 0.3 mm and the distance between octagons, d, is 0.845 mm. To analyze this structure, it is embedded at the middle of a transverse electromagnetic (TEM) waveguide,6 which has proper magnetic and electric boundary conditions on walls. The resonance frequency of this structure depends on the gap dimension (g). By increasing the gap, the capacitance in inductance–capacitance (LC) circuit model of the unit cell decreases. The decrement of the capacitance results in the increment of the resonance frequency of the structure.
Effectively Optimized Dual-band Frequency Selective Surface Design for GSM Shielding Applications
Published in IETE Journal of Research, 2022
B. Döken, Ali Berkay Koç, İhsan Güney Koç, Mikail Altan
Basic FSS geometries analyses can be utilized by an equivalent circuit model with high accuracy. However, equivalent circuit model analyses start to lose accuracy for complex FSS geometries. Thus, simple equivalent circuit model shown in Figure 2 is employed in this work to determine the relationship between the frequency response of the surface and its geometric parameters. In this model “C1” and “C2” refer to the equivalent capacitance, “L1” and “L2” refer to the equivalent inductance values of the outer and inner conductors, respectively. “M” is the mutual inductance between inner and outer conducting geometries. The equivalent capacitance value is directly proportional to the width of the conductive paths and inversely proportional to the distance between them. The equivalent inductance value is directly proportional to the length and inversely proportional to the width of the conductor paths. The resonance frequencies of the FSS are inversely proportional to as shown in Eq.1. Since the equivalent capacity and inductance values vary with the design's geometric parameters, the resonance frequency can be optimized by the achieved information from the equivalent circuit model. The dielectric substrate that supports the periodic element geometries is chosen as FR4 due to its availability in the market and affordable price. FR4 has a dielectric permittivity of 4.4 and loss tangent of 0.02. The thickness of the FR4 is chosen as 1 mm since they can be easily found in the market.
Compact Bandstop Microstrip Line Filter Using U-Shaped Slot
Published in IETE Journal of Research, 2022
Mamoon A. Al-Atrakchii, Khalil H. Sayidmarie, R. A. Abd-Alhameed
The effects of the loss tangent of the substrate on the insertion loss are demonstrated in Figure 6. The used value for the loss tangent of the FR4 was δ = 0.025. Another simulation was run for an assumed loss tangent of δ = 0.0025. The figure shows noticeable improvements in the reflection coefficient across the two stopbands, as well as lower insertion loss across the passbands. Table 1 compares the exact values, where it can be seen that about 2 and 5 dB improvements are obtained in the reflection coefficient at the lower and upper bands, respectively. The corresponding values in the insertion loss are 8 and 7 dB. These results mean that better performance can be obtained by using a low loss substrate.
Octagonal DGS based dual polarised ring-shaped antenna for MIMO communications
Published in International Journal of Electronics, 2019
Henridass Arun, M. Gulam Nabi Alsath
Figure 1 illustrates the geometry of the proposed dual polarised antenna. The feed lines are arranged orthogonally to induce dual polarisation. Proposed dual polarisation antenna is fabricated and S parameters are measured using Agilent technologies ENA series E5070A 2port RF Vector Network Analyser. Figure 2 shows the fabricated prototype using FR-4 material with a thickness of 1.6 mm. The S parameter characteristic of the proposed dual polarisation antenna is shown in Figure 3. From the measured S11 value, the impedance bandwidth offered by the dual polarised antenna is about 280 MHz which is from 1770 MHz to 2050 MHz.