Metamaterial Loaded Frequency Tunable Electrically Small Planar Patch Antenna

A novel metamaterial structure has been proposed for Electromagnetic Compatibility (EMC) applications. A patch antenna with dimension of 18 mm × 13.9 mm and resonating at 5 GHz has been designed and the effect of Double Negative (DNG) metamaterial loading for the patch size reduction as well as a lowering in resonance frequency for the fixed size patch antenna has been proposed. A size reduction of 72.5% in the patch antenna has been obtained with the loading of this metamaterial structure and the effect of loading the metamaterial shows that without reducing the size, the patch antenna can work at 3.7 GHz resonance, providing a lowering in resonance frequency by 26%. The metamaterial structure consists of two concentric loops with an outer radius of 3.1 mm. The width of the ring is 1.0 mm and the split is 0.5 mm and has been designed over a 1.57 mm thick Fr4 substrate. The bending effect of the patch antenna with and without metamaterial loading and its comparison with the planar patch antenna has been also shown here. The metamaterial structure has shown its resonance at 5 GHz and its permittivity and permeability behavior over the desired frequency range has been plotted. The simulation of traditional patch antenna and patch antenna over metamaterial has been compared for its return loss, VSWR, gain and efficiency. Finally, a spice circuit for the S parameter of the metamaterial, patch antenna and patch antenna loaded with metamaterial has been obtained using Matlab and ADS for its equivalence to 3D field solver and its comparison has been plotted for its verification.

The paper presents a small patch antenna with a folded patch feed and double shorting walls. In order to enhance the impedance bandwidth further, an additional aperture is introduced on the upper patch. The proposed antenna exhibits a measured impedance bandwidth of more than 70% for VSWR/spl les/2. It is applicable to modern wireless applications.

ABSTRACTIn this letter, it is proposed to use metasurface (MS) to miniaturize patch antenna. The MS studied is composed of two layers, layers 1 and 2. Layer 1 has simple rectangular microstrip lines as unit cells and layer 2 has the complimentary pattern of layer 1. The MS is placed on top of and in direct contact with a small patch antenna, forming a miniaturized‐patch antenna operating at 4 GHz. For comparison, another patch antenna without using MS is designed to operate at the same frequency. Both antennas are studied using computer simulation and measurement. Results show, with the use of the MS, the patch antenna can have the size reduced by 67%, yet achieving a similar performance. The simulated and measured results in reflection coefficients, efficiencies, realized peak gains, and radiation patterns of the antennas are presented. The cable effects caused by the feeding cable used in measurement are studied. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2050–2056, 2015

Metamaterials are assemblies of metallic and/or dielectric materials with properties that are not readily found in naturally existing materials. Hence, metamaterial structures are commonly loaded on/near the patch, embedded in the substrate, loaded/etched from the ground plane or placed as a superstrate layer for enhancing bandwidth and gain, and size miniaturization of conventional patch antennas. The demand for wide bandwidth, high gain, and compact antennas is highly contemplated in recent wireless communication research studies. Despite their lightweight, ease of fabrication, low profile, and simplicity for integration, patch antennas have performance limitations as result of their narrow bandwidth, lower gain, larger size, and lower power handling capacity. To address these problems, metamaterial-based antennas have gained massive interest. There exist inadequate literatures about review of current state of extensive study reports on metamaterial application for patch antenna performance enhancement. Thus, this paper has reviewed and discussed latest research works on metamaterial applications for performance enhancement of planar patch antennas.

A low-profile miniature antenna with very wide bandwidth is proposed for emerging multimode devices. It comprises a small circular patch antenna loaded by a metallic annular-ring and located on a laminate with a slotted ground plane. The design achieves a very compact low-profile antenna with broadband performance. By optimizing the parameters of the annular-ring patch antenna, very broadband characteristics can be obtained. The measured results show that the antenna achieves a 10 dB return loss from 1.383 GHz to 2.210 GHz, (827 MHz) ie about 47% with respect to the centre frequency 1.796 GHz. The measured results are in good agreement with the simulated results. The radiation patterns and gains are also presented. The working frequencies for the proposed antenna include the GPS frequency (1.575 GHz), DCS band (1.710 GHz-1.880 GHz), DECT, GSM1800 and the UMTS (1.920 GHz-2.170 GHz) band.

A small size patch antenna with high gain and high front-to-back (F/B) ratio has been newly developed. The antenna consists of two elements, that is, RF exiting element arranging on the front side and parasitic one on the back. The latter is terminated by the reactance. The antenna is as small as 80times80times8 mm in size and shows the gain and F/B ratio of 6 dBi and 15 dB at 950 MHz band, respectively. The obtained results are about 2 dB and 10 dB higher in gain and F/B ratio, respectively as compared with the conventional patch antenna. The size dependence of the performance has been investigated for antenna design by the simulation. The result shows that decreasing the element width with sacrificing the increase of thickness is found to be effective for minimizing the antenna volume.

This paper comprises work concerned with the design of multiband (six) and small size Microstrip patch antennas (MPA)for the new generation 5G devices and Radar application. The suggested antenna has a small structure of 27×38.62×1.575 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , antenna operates at frequencies 9.92, 16.42, 23.12, 27.24, 29.9, 35.33 GHz which are many of the frequencies expected to be operated for the 5G mobile communications and Radar application. Compared to research interested in this field, the proposed antenna gives very good gain and directional radiation pattern at all frequencies. the excitation of the patch antenna at the fundamental and higher harmonics is considered. Odd harmonics (1, 3, 5) form a maximum perpendicular to the antenna, and even ones form a dip along the normal. Additionally, the problem of antenna matching is solved the suggested antenna has a thickness of 1.575 mm on DUROID (TM) substrate. In this work the antenna geometry and different parameters such as radiation pattern plot, return loss and gain plots, and directivity plot are obtained and discussed.

In this article a simple and small size wideband square patch antenna has been examined for band notch characteristics. In order to broadening the band width of the simple patch antenna, the role of partial ground has been critically studied and analyzed. The presented methodology reveals that the implementation of meander line fractal shaped defected ground structure not only augment the band width of the antenna but also provide a notched band at 12.14 GHz required to reject the interference for existing wireless communication. A prototype of the proposed antenna has been fabricated to validate the simulated results. The measured and simulated results are in good agreement.

An original lightweight, low-cost and compact patch antenna with short-circuited elements, fed by a coaxial probe, is presented. The resonance length of the antenna is around 0.094 /spl lambda//sub 0/. The resonant frequency can be reduced by /spl sim/81% when compared with the resonant edge of a conventional patch antenna.

A comparative study to determine the most highly sensitive resonant frequency among the first four resonant frequencies of a conventional patch antenna and defected ground structure (DGS)-loaded patch antennas using commonly used DGS geometries in the literature, such as a rectangular slit, single-ring complementary split ring resonators (CSRRs) with different split positions, and double-ring CSRRs (DR-CSRRs) with different locations below the patch, for relative permittivity measurement of planar materials was conducted. The sensitivity performance for placing the DGS on two different locations, a center and a radiating edge of the patch, was also compared. Finally, the effect of scaling down the patch size of the DGS-loaded patch antenna was investigated in order to enhance the sensitivities of the higher order resonant frequencies. It was found that the second resonant frequency of the DR-CSRR DGS-loaded patch antenna aligned on a radiating edge with a half scaled-down patch size shows the highest sensitivity when varying the relative permittivity of the material under test from 1 to 10. In order to validate the simulated performance of the proposed antenna, the conventional and the proposed patch antennas were fabricated on 0.76-mm-thick RF-35 substrate, and they were used to measure their sensitivity when several standard dielectric substrate samples with dielectric constants ranging from 2.17 to 10.2 were loaded. The measured sensitivity of the second resonant frequency for the proposed DGS-loaded patch antenna was 4.91 to 7.72 times higher than the first resonant frequency of the conventional patch antenna, and the measured performance is also slightly better compared to the patch antenna loaded with a meander-line slot on the patch.

As a part of this work a small patch antenna probe was developed to measure the variation in the electric field produced by gradient coils within an MRI in the presence of any active implantable medical devices (AIMDs). This probe was designed, fabricated, and tested within a gradient coil mimicking dB/dt exposure platform. A 2×1 cm small patch antenna followed by an instrumentational amplifier was chosen to measure the electric fields. Probe was fabricated using a 4-layer PCB. The fabricated probe was used to monitor the electric fields within the phantom in the gradient coil environment. To verify the observed behavior of the probe a simulation study was performed using Sim4Life. This study aims to assess the performance of this probe in a tissue mimicking environment within the coil.

This paper presents the design of wireless power transmission circuit on a small planar wide-band antenna. The proposed rectifying circuit consists of a microstrip line, a Schottky detector diode and a capacitor. Our proposed rectifying circuit can work at 2.45 GHz, 3.8 GHz and 5.8 GHz, namely, multiband operation, and circuit size is 56 mm × 43 mm × 1.6 mm. The proposed small planar wide-band antenna has a maximum gain of 1.26 dBi at 2.5 GHz, 0.37 dBi at 3.8 GHz and 3.32 dBi at 5.8 GHz. The maximum conversion efficiencies of this circuit achieved at free space are 26.8%, 29% and 43.3% at 2.5, 3.5 and 5.8 GHz with load resistances of 2000 Ω, 510 Ω, 1300 Ω and 0 dBm input power level.

This chapter focuses on designing small antennas used by Ultra Wideband (UWB) wireless systems. The study has been taken from the conventional rectangular manuscript patch antenna to miniaturize the size of used antenna to be more suitable for future 5G system applications. These applications are dealing with high data transmission rates over a very large spread spectrum frequency (3.1–10.6 GHz), so that, many challenges are provided in the antenna design. The main objective of this research is to design, and analyze two small manuscript patch antennas to satisfy UWB technology requirements. Several techniques were used to optimize the UWB bandwidth performance such as radiator dimensions, planar ground plane, and unprinted gaps between ground plane and radiators. Therefore, this work introduces two designs of microstrip-fed, small, and low profile which are called ax-shaped and socket-shaped patch antennas. It has been demonstrated numerically that the proposed antennas are suitable for UWB systems. They can provide satisfactory frequency domain performance (less than −10 dB return loss), including ultra-wide bandwidth with nearly omni-directional radiation patterns, and relatively good current density over the radiator parts of the proposed antenna designs.KeywordsRadiation PatternGround PlanePatch AntennaMicrostrip AntennaAntenna DesignThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

In this paper, a very new proposed model of TCAS (Traffic Collision Avoidance System) Antenna, installed in an Aircraft has been designed using HFSS (High Frequency Structure Simulator) Software. This new proposed antenna is a Slotted Microstrip Patch Antenna that can be used as a TCAS Directional Antenna. A RF MEMS Switch has also been designed using HFSS Software. This RF MEMS Switch is going to be used in TCAS Antenna for signal transmitting and receiving purpose. Ferrite Material Phase Shifters will also be used to steer the radiation pattern of the TCAS Antenna so that it can track a wide range of surveillance area. A mathematical concept has been developed for this Phase Shifter.

A small low-profile linearly-polarized patch antenna is proposed for universal ultra-high-frequency (UHF) RF identification (RFID) applications. The antenna is composed of a folded patch and an improved L-shaped feeding strip. It works from 834 to 970 MHz with SWR less than 2, thus the proposed antenna is universal for UHF RFID applications worldwide at the UHF band of 840-960MHz. Moreover, the air thickness of the patch antenna is 20mm, reduced to only 0.06λ. Stable unidirectional radiation patterns, low cross-polarization level and stable gain are achieved over the pass-band.