Step shape antenna for MIMO applications

A simple dual-band antenna design and implementation method is proposed in this work, based on the equivalent media properties inspired by resonant metamaterial elements. The equivalent circuit model of dual-band patch antennas based on a complementary split ring resonator (CSRR) is presented and validated. The dual-band patch antenna is designed etching a CSRR in the patch of a conventional rectangular microstrip patch antenna. The first resonance is governed by the quasi-static resonance of the CSRR while the second resonance is originated by the rectangular patch. The fact of etching a CSRR on a rectangular patch antenna also produces a miniaturization of a conventional patch antenna. The equivalent circuit model proposed in this letter is sound in order to understand the functionality of dual-band patch antennas based on a CSRR. Good agreement between simulation, equivalent circuit model and experimental results is shown and discussed. These results lead the equivalent circuit model to become a simple and straightforward tool for the design of this type of multiband antennas, of low cost and versatile operation for a broad range of wireless communication systems.

In this paper, metamaterial superstrate is proposed to enhance the performance parameters of conventional rectangular microstrip patch antenna. The metamaterial is designed using proposed diagonally connected square split ring resonator (DC SSRR). The designed DCS SRR shows the negative values of refractive index for broadband frequency band, 5.0 GHz to 12 GHz. Use of metamaterial superstrate on conventional rectangular microstrip antenna improves the return loss by 18 dB and enhances the gain, bandwidth and radiation efficiency by 1.2 dBi, 28 MHz and 17.5% respectively. The permittivity, permeability and refractive index of metamaterial are numerically computed using MATLAB. All performance parameters of antenna and S-parameters of DC SSRR are obtained using commercially available full wave electromagnetic simulator HFSS based on finite element method and verified by measured results. Good agreement is found between simulated and measured results.

RFID Tags, typically, require ultra-small antennas and at 900 MHz most of the designs end up being meandered line wire antennas. These may not be suitable because such antennas are heavily influenced by the object on which they are placed. An antenna with a ground plane, such as a microstrip antenna, is a more suitable candidate in that scenario, however, typically micrsotrip patch antennas are large in size. In this paper, we introduce a highly miniaturized microstrip antenna with multiple slots and a superstrate with high-permittivity material. The size of the microstrip antenna at 900MHz is reduced by 87.5% as compared to a conventional rectangular microstrip patch antenna at 900MHz. The gain of the miniaturized antenna is 0.36dBi, achieving 40% efficiency, which is decent enough for short to medium range RFID applications.

In this paper, the characteristics of a small antenna using an H-shaped microstrip patch are studied. Significant reduction of antenna size can be realized when the H-shaped patch is used instead of the conventional rectangular microstrip patch antenna. The theoretical analysis is carried out based on the finite-difference time- domain (FDTD) method. The FDTD programs are developed and validated by available measurement results. The effects of various antenna parameters on the resonant frequency and radiation patterns are shown. Several design curves are presented, which are useful for practical antenna design. The electric current distributions on the patch and those on the ground plane are described, together with the results illustrating the electric field distributions under the patch. This antenna is suitable for applications where small size and broad beamwidth are required.

The characteristics of a small antenna using an H-shaped microstrip patch antenna is analyzed. Significant reduction of antenna size can be realized when the H-shaped patch is used instead of the conventional rectangular microstrip patch antenna. The effect of various antenna parameters like substrate height, radius of shorting post and feed point are analyzed and their effect on return loss is shown.

This paper presents a novel compact microstrip patch antenna for three-band application, consisting of a main straight arm and four spiral branches. This antenna is characterized by the very small size of only 0.191 /spl lambda/g by 0 212 /spl lambda/g at the first resonance frequency of 5.34 GHz, which represents a size reduction of 60% compared to a conventional rectangular microstrip patch antenna. The results indicate that the return loss is better than 10 dB and that the gain is about 6 dB in each band.

This paper proposes unique design technique using defected microstrip surface (DMS) for the suppression of higher mode, reduced cross polarization (XP) and improved isolation. The proposed technique can be easily adapted to any conventional working rectangular microstrip patch antennas (RMPA) in the practical applications. The modification can be made by etching the rectangular slots called DMS of optimized dimensions in the rectangular microstrip patch. This will enhance the radiations by suppressing XP radiations and eliminates nearby undesired higher order mode, which is the source for the XP radiations. In this design the conventional RMPA is designed to resonate at 3.04 GHz with broad side radiations with co-polarized peak gain of 5.2dBi and XP of -15.5dB. The proposed RMPA resonates at the same frequency with a gain of 6dBi. The XP is significantly suppressed by 31dB and it is -46.5dB over the span of ±500, with co-pol to cross-pol isolation of 52.5dB is achieved for S-band applications. The performances of the designed antennas have been experimentally verified.

This paper presents the design and simulation of 30°-30°-120° triangular microstrip patch antenna miniaturization using shorting pin for S-band frequency operation. The analysis of miniaturized triangular microstrip antenna with shorting pin is performed by Ansys HFSS based simulation results. The conventional and compact triangular microstrip patch antenna shows the resonant frequency at 2.2 GHz and 2.4 GHz with gain of 1.2 dB and 1.7 dB respectively. Here the conventional triangular microstrip patch antenna area is miniaturized upto 31% through the shorting pin. The comparison between the conventional and compact triangular microstrip patch antenna are presented and discussed in this paper. The proposed compact triangular microstrip patch antenna is often suitable for integration with Bluetooth and WLAN devices with reduced design complexity.

<span>This paper presents a bandwidth enhancement of a dual-band bi-directional rectangular microstrip patch antenna. The novelty of this work lies in the modification of conventional rectangular microstip patch antenna by using the combination of two techniques: a complementary split ring resonator (CSRR) and a defected patch structure (DPS). The structure of antenna was studied and investigated via computer </span><span>simulation technology (CST). The dimension and position of CSRR on the ground plane was optimized to achieve dual bandwidth and bi-directional radiation pattern characteristics. In addition, the bandwidths were enhanced by defecting suitable shape incorporated in the microstrip patch. A prototype with overall dimension of 70.45×63.73 mm<sup>2</sup> has been fabricated on FR-4 substrate. To verify the proposed design, the impedance bandwidth, gain, and radiation patterns were carried out in measurements. The measured impedance bandwidths were respectively 560 MHz (3.08-3.64 GHz) and 950 GHz (4.64-5.59 GHz) while the measured gains of each bandwidth were respectively 4.28 dBi and 4.63 dBi. The measured radiation patterns were in good agreement with simulated ones. The proposed antenna achieves wide dual bandwidth and bi-directional radiation patterns performances. Consequently, it is a promising candidate for Wi-Fi or 5G communications in specific areas such as tunnel, corridor, or transit and rail.</span>

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 compact dual band planar hexagonal patch antenna with meander transmission line fed by co-planar wave guide is proposed. The antenna resonates at 2.51-2.69 GHz and 3.52-4.10 GHz, which makes it suitable for 2.57 GHz (LTE) and 3.78 GHz worldwide interoperability for microwave access (WiMAX) frequency bands, respectively. This hexagonal patch is designed on FR-4 substrate with 1.6 mm thickness. The antenna is fed by a meandered transmission line which reduces the overall size of the antenna. The planar hexagonal patch antenna is smaller in size as compared with conventional microstrip patch antenna and has a good agreement with the simulation results. Hence, the antenna is suitable for LTE and WiMAX band applications.

Due to its low profile, the microstrip antenna has found many applications in personal communication systems. And, owing to the miniaturization of communication equipment, designs for reducing the size of the microstrip antenna have received much attention. One of the effective ways to reduce the patch size of the microstrip antenna is to introduce a shorting pin at the edge of the patch. Based on this technique, several novel designs of the compact microstrip antennas are described. The antenna size can be reduced to less than 50% of the size of a conventional microstrip antenna. By incorporating the meandering of the patch, the electrical length of the patch can be further increased. The characteristics of such compact microstrip antennas are experimentally studied. Comparisons between the compact and conventional microstrip patch antennas are also given.

Body-centric wireless networks are used for connectivity between on-body and on-off body communications for various applications for rescue, diagnostics and medical usage. Multiple features of modern portable and wearable devices necessitate antenna operation at a number of frequencies. A compact, low profile and multi-band antenna is presented for body-centric wireless networks in this study. The conventional microstrip rectangular patch antenna has been converted into a multi-band antenna by using layers of mercury and liquid crystal polymer (LCP). The antenna performance in free space and in body-mounted configurations are evaluated and compared using computer simulations. The proposed antenna supports six frequencies for operation at ISM/Wi-Fi/C band. A minimal shift in the operating frequencies while operating in on-body configuration makes this the proposed antenna very resilient to frequency de-tuning caused by the human body presence. The antenna also offers high peak gain values (>7.68 dBi) in the two configurations at all of the operating frequencies.

The rectenna as a device, is critical for achieving long-distance wireless power transfer. The centrality of this study is focused on adding to the collective knowledge of the subject matter, by providing a new perspective in terms of an alternative design for the antenna component of the rectenna. Essentially, this study features a novel “3-point star” design which was simulated in comparison with the conventional square microstrip patch antenna design. Both designs (i.e., operating at the Wi-Fi band 2.4 GHz), were assessed in terms of simulated performance parameters: gain, directivity, return loss, radiation pattern, and efficiency. From the simulation results, the proposed “3-point star” design, though slightly less efficient exhibited improved performance over the conventional square patch alternative, in terms of gain, directivity, and return loss. For the rectifying component, a greinacher voltage-doubler (with two HSMS2820 diodes), was designed separately and simulated over a range of input power levels (10dBm—34dBm), for 220-Ω, 380-Ω and 810-Ω load resistances, respectively. A maximum conversion efficiency of 88.02% was achieved at 28dBm for an 810 Ω load resistance. All design simulations were executed using Advanced Design System (ADS) software.

In this paper, uniplanar design of harmonic/higher order mode suppression microstrip antenna is proposed in contrast to the usual defected ground plane structure/photonic bandgap techniques. The main advantages of present design include ease of integration without the requirement of air gap beneath the antenna and less sensitive to the alignment and mounting issues. The suppression of the higher order harmonics is achieved by using a compact multi-stub unit resonator, which occupies only 37% size of patch dimensions. This resonator consists of a printed metallization in the same layer. Comparing with conventional inset-fed square microstrip patch antenna, the radiated power of the proposed antenna at the first two higher order mode frequencies is reduced by 14 dB and 10 dB, respectively, while exhibiting the good performance at the fundamental operating frequency.