Showing papers on "Metamaterial antenna published in 2022"

Metamaterials and Metasurfaces for Wireless Power Transfer and Energy Harvesting

Abstract: A comprehensive review of metamaterials and metasurfaces for wireless power transfer (WPT) and wireless energy harvesting (WEH) is presented in this article. According to the features of the electromagnetic field from the source to the receiver, WPT is divided into nonradiative near-field technology and radiative (near and far-field) technologies. Many different and important designs are reviewed and compared. It is shown that metamaterials and metasurfaces can significantly improve the power transfer efficiency and operational distance for WPT systems. They can also improve the energy conversion efficiency of wireless energy harvesters by making the reception less sensitive to incident wave angle and polarization. A rectenna is a critical element for both WPT and WEH. It is shown that metamaterial-based rectennas can achieve a higher RF to dc conversion efficiency. Furthermore, metamaterials can also be used as either parasitic elements or loading components to improve WEH performance in terms of circuit size, beamwidth, and conversion efficiency. Future development directions and opportunities of metamaterials and metasurfaces for WPT and WEH are also proposed in this article.

Performance Analysis of Metamaterial-Inspired Structure Loaded Antennas for Narrow Range Wireless Communication

Abstract: Nowadays, the demand for low-cost, compact, and interference rejected antennas with ultrawideband capability has been increased. Metamaterial-inspired loaded structures have capability of providing exceptional solutions for narrow range wireless communication and low consuming power while transmitting and receiving the signal. It is a difficult task to construct ideal metamaterial-inspired antennas with a variety of features such as extremely large bandwidth, notching out undesirable bands, and frequency. Metamaterial-inspired structures such as SRR and CSRR, and triangle-shaped TCSRR are most commonly used structures to achieve optimized characteristics in ultrawideband antennas. In this paper, an extensive literature survey is accomplished to get conception about metamaterial-inspired patch antennas. This review paper elucidates variants of metamaterial-inspired structures/resonators utilized in order to acquire sundry applications such as WiMAX, WLAN, satellite communication, and radar. Various researchers have used different methodology to design, stimulate, and analyze the metamaterial-inspired structure loaded antennas. Also, the results of different metamaterial-inspired antennas such as bandwidth, gain, return loss, and resonant frequency have been also represented in this paper. This manuscript also gives brief introduction about the metamaterial, its types, and then its application in microstrip patch antenna over the last decade. This manuscript throws light over the various studies conducted in the field of metamaterial-inspired antenna in the past. It has been seen that with the inclusion of metamaterial in conventional antenna, various characteristics such as impedance bandwidth, reflection coefficient, gain, and directivity have been improved. Also, frequency rejection of narrow bands which exits in ultrawideband frequency range can be done by embedding metamaterial-inspired structures such as SRR and CSRR.

Improvement of low-profile microstrip antenna performance by hexagonal-shaped SRR structure with DNG metamaterial characteristic as UWB application

Abstract: A metamaterial is any material engineered with a property not discovered in naturally occurring materials. Its existence is important in the development and application of modern technology in this century. Furthermore, Its characteristics such as high sensitivity and gain can be potentially applied in antenna technology. In this research, the metamaterial implementation was used to improve low-profile microstrip antennas as ultra-wideband (UWB) applications. The proposed metamaterial consists of variations of one to four hexagonal shape split ring resonator (SRR-H) elements. This study was carried out through simulation and experiments which were operated in the frequency range 0.05–9 GHz. Based on the results, the proposed antenna with the variation of the SRR-H elements provides increased performance than the without SRR-H. The highest double-negative (DNG) metamaterial characteristic of the SRR-H four-element structure provides the highest antenna performance compared to others. The given working frequency occurs at 5.98 GHz with an increase in bandwidth of 47.49% from without SRR-H. The antenna metamaterial structure also responds by providing an ultimate gain radiation pattern of 5.97 dBi at a 45-degree angle in the Quadrant II region. Thus, the performance of the proposed antenna shows the potential for use in UWB technology.

A novel miniaturized reconfigurable microstrip antenna based printed metamaterial circuitries for 5g applications

Abstract: |A novel recon(cid:12)gurable sub-6 GHz microstrip patch antenna operating at three resonant frequencies 3.6, 3.9, and 4.9 GHz is designed for 5G applications. The proposed antenna is constructed from metamaterial (MTM) array with a matching circuit printed around a printed strip line. The antenna is excited with a coplanar waveguide to achieve an excellent matching over a wide frequency band. The proposed antenna shows excellent performance in terms of S 11 , gain, and radiation pattern that are controlled well with two photo resistance. The proposed antenna shows different operating frequencies and radiation patterns after changing the of photo resistance status. The main antenna novelty is achieved by splitting the main lobe that tracks more than one user at the same resonant frequency. Nevertheless, the main radiation lobe can be steered to the desired location by controlling the surface current motion using two varactor diodes on a matching circuit.

Design of Miniaturized High Gain Bow-Tie Antenna

Abstract: A high gain low-frequency bow-tie antenna with artificial magnetic conductor (AMC) and metamaterial lens for ground penetrating radar (GPR) is proposed. First, a bow-tie antenna working in 348–772 MHz frequency band is designed. The substrate is a square with side length of 420 mm. A periodic AMC reflector is designed. The in-phase reflection region of the unit is 481 MHz–1.44 GHz. The results show that the gain of antenna loaded with reflector is increased by 5 dB. A metamaterial lens based on the zero-index metamaterial element is also proposed to improve the gain. The zero refractive index frequency point is 810 MHz, the unit size of the metamaterial is 60 mm, and the lens size is consistent with the antenna substrate size. The gain of the antenna loaded with AMC reflector and the metamaterial lens is increased by 6.5 dB and the front-to-back ratio is 23 dB. The directivity of the antenna is further optimized. The measured results are in good agreement with the simulations.

A Wireless Power Transfer System Based on Dual-Band Metamaterials

Abstract: Wireless power transfer (WPT) received widespread research in various field, such as wireless power in consumer electronics and electric vehicles. Recent researches have shown that adding metamaterials to the WPT system was an effective method to enhance transmission efficiency and distance. In view of the fact that traditional metamaterial slab often had a single working frequency point and was not suitable for multifrequency WPT, this letter analyzed and discussed the mechanism of magnetic negative metamaterial enhancing WPT efficiency. Moreover, two kinds of metamaterials, self-resonant dual-band negative permeability (SRDB-NPM) metamaterial and externally compensated dual-band negative permeability (ECDB-NPM) metamaterial, were designed. Finally, the effectiveness of two kinds of dual-band metamaterials to improve the efficiency at two different frequencies is verified by simulation and experiment.

Wide Bandwidth Enriched Symmetric Hexagonal Split Ring Resonator based Triple Band Negative Permittivity Metamaterial for Satellite and Wi-Fi Applications

Abstract: Bandwidth is a vital factor for the transmission phase of satellite data that plays an important role in satellite performance. This paper presents a wide bandwidth enriched metamaterial consisting of symmetric hexagonal split ring resonator (SRR) with triple band negative permittivity and refractive index and near zero permeability for satellite and Wi-Fi applications. The electrical dimension of the designed metamaterial unit cell is 0.17λ × 0.17λ where wavelength (λ) is computed at a first resonance frequency and developed on a cheap dielectric material FR-4 (lossy) with a thickness of 1.6 mm. The proposed metamaterial contributes triple resonances for the transmission coefficient (S21) at the frequencies of 5 GHz, 6.88 GHz and 8.429 GHz with the magnitude of −33.79, −21.7 and −25.18 dB, respectively covering C and X bands through the numerical execution of CST microwave studio 2019. The effective bandwidth of the unit cell are 1.67 GHz (3.89 to 5.56 GHz), 0.52 GHz (6.59 to 7.11 GHz) and 0.98 GHz (7.98 to 8.96 GHz) where the value of S21 less than −10 dB. The first resonance frequency is used to high speed-bandwidth enriched Wi-Fi and satellite band. Wi-Fi is usually faster using 5 GHz frequency band. The rest of the resonance frequency can be used in satellite applications. A negative permittivity has been perceived at frequencies of 5 – 6.066 GHz, 6.88 – 7.409 GHz, 8.429 – 10.061 GHz using Nicolson-Ross-Weir (NRW) methods with MATLAB code. The dependence of the resonance frequencies on the design parameters, substrate thickness, dielectric materials, the influence of the different structure of unit cell has also been examined. The designed unit cell structure with equivalent circuit diagram are analyzed and validated using Advanced Design System (ADS) simulator that exhibits similar to the S21 of the proposed structure. Furthermore, measurement results and Ansys high-frequency structure simulator (HFSS) simulator results are also employed to verify the outcome. Due to the overall performance, such as wide bandwidth, excellent effective parameters of the designed structure, the proposed research can be very suitable for satellite and Wi-Fi applications.

A Metamaterial Inspired AMC Backed Dual Band Antenna for ISM and RFID Applications

Abstract: This work presents the design and fabrication of a metamaterial-based stimulated dual band antenna on FR4 material (dielectric constant 4.3) to operate in Industrial, Scientific and Medical (ISM) and Radio-frequency Identification (RFID) applications. The antenna model had an overall dimension of 70 × 31 × 1.6 mm3 with etched T-slots and L-slots for dual band resonance. The main objective of this work was to enhance the gain performance characteristic at the selected dual band frequencies of 0.915 GHz and 2.45 GHz. Initially, it achieved a narrow bandwidth of 0.018 GHz with a gain of 1.53 dBi at a lower frequency, and 0.13 GHz of bandwidth featuring 4.49 dBi of gain at a higher frequency. The antenna provided an impedance bandwidth of 2% (0.905–0.923 GHz) and 5% (2.382–2.516 GHz) at two resonating frequencies. The antenna was integrated with a designed novel AMC structure to enhance the gain in CST Microwave Studio software with the finite integration method. The characteristic features of the AMC unit cell were observed at 0.915 GHz and 2.45 GHz frequencies and after antenna integration, the final prototype achieved a gain of 2.87 dBi at 0.915 GHz and 6.8 dBi at 2.45 GHz frequencies.

Two-Degree-of-Freedom Control of Field Distribution on Nonreciprocal Metamaterial-Line Resonators and Its Applications to Polarization-Plane-Rotation and Beam- Scanning Leaky-Wave Antennas

Abstract: Two-degree-of-freedom control of field distribution on the pseudotraveling wave resonator using nonreciprocal metamaterial lines is demonstrated for the first time. Dynamic control of current distribution on the resonator is given based on circuit theory. We employed a normally magnetized ferrite microstrip line-based composite right-/left-handed (CRLH) transmission line as a metamaterial with variable phase-shifting nonreciprocity. Numerical simulation results show that the phase gradient of the fields along the resonator is controlled by the applied dc magnetic field to the ferrite. By changing the reflection coefficients of two reflectors inserted at both ends of the CRLH line section, current distribution along series and shunt branches of the unit cell is continuously and drastically changed under the resonance. The variable field distribution was implemented to polarization-plane-rotation and beam-scanning leaky-wave antennas. The experimental demonstration verifies our basic concept and shows the performance of the prototype antenna with a beam scanning angle of 20° and a continuous rotation angle of polarization plane by ±70° at the fixed frequency.

SRR metamaterial-based broadband patch antenna for wireless communications

Abstract: Abstract This paper presents the design and analysis of a broad-band patch antenna using split ring metamaterial. The SRR metamaterial structures are embedded in a unique and novel way in the patch antenna, so that subwavelength modes get introduced in the patch cavity and a broad bandwidth antenna with good performance characteristics is obtained. A rectangular microstrip patch antenna is taken as a reference antenna, which resonates at a frequency of 5.2 GHz and has an impedance bandwidth of 70 MHz. To improve the bandwidth of the patch antenna, firstly the split ring resonator (SRR) is designed according to the reference patch antenna. The optimized SRR metamaterial is placed in between the patch and ground plane of the proposed antenna. The – 10 dB impedance bandwidth of the metamaterial-embedded proposed antenna is 1.63–4.88 GHz and has an average gain of 4.5 dB. The Prototype of the proposed antenna and reference antenna is fabricated and experimental results are obtained. Experimental and simulated results are in good agreement. The presented antenna can be used for LTE, GSM, WiMAX, Bluetooth, and other wireless applications.

Tunable Compact Metamaterial-Based Double-Negative/Near-Zero Index Resonator for 6G Terahertz Wireless Applications

Abstract: This paper introduces the tunability performance, concept, and analysis of a unique and miniaturized metamaterial (MTM) unit cell covering the upcoming 6G applications. The proposed metamaterial consists of two metallic star-shaped split-ring resonators (SRR). It has a line segment placed in the middle of the structure, which can feature tunable characteristics. The proposed design provides dual resonances of transmission coefficient S21 at 0.248 and 0.383 THz with a significant operating frequency span of 0.207–0.277 and 0.382–0.390 THz, respectively. Moreover, wide-range achievement, negative permittivity, double-negative (DNG) refractive index, and near-zero permeability characteristics have been exhibited in two (z and y) principal wave propagation axes. The resonance frequencies are selective and modified by adjusting the central slotted-strip line length. Furthermore, the metamaterial is constituted on a polyimide substrate while the overall dimensions are 160 × 160 μm2. A numerical simulation of the proposed design is executed in CST microwave studio and has been compared with advanced design software (ADS) to generate the proposed MTM’s equivalent circuit, which exhibits a similar transmission coefficient (S21).

Inkjet Printed Metamaterial Loaded Antenna for WLAN/WiMAX Applications

Abstract: : In this paper, the design and performance analysis of an Inkjet-printed metamaterial loaded monopole antenna is presented for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The proposed metamaterial structure consists of two layers, one is rectangular tuning fork-shaped antenna, and another layer is an inkjet-printed metamaterial superstate. The metamaterial layer is designed using four split-ring resonators (SRR) with an H-shaped inner structure to achieve negative-index metamaterial properties. The metamaterial structure is fabricated on low-cost photo paper substrate material using a conductive ink-based inkjet printing technique, which achieved dual negative refractive index bands of 2.25–4.25 GHz and 4.3–4.6 GHz. The antenna is designed using a rectangular tuning fork structure to operate at WLAN and WiMAX bands. The antenna is printed on 30 × 39 × 1.27 mm3 Rogers RO3010 substrate, which shows wide impedance bandwidth of 0.75 GHz (2.2 to 2.95 GHz) with 2 dB realized gain at 2.4 GHz. After integrating metamaterial structure, the impedance bandwidth becomes 1.25 GHz (2.33 to 3.58 GHz) with 2.6 dB realized gain at 2.4 GHz. The antenna bandwidth and gain have been increased using developed quad SRR based metasurface by 500 MHz and 0.6 dBi respectively. Moreover, the proposed quad SRR loaded antenna can be used for 2.4 GHz WLAN bands and 2.5 GHz WiMAX applications. The contribution of this work is to develop a cost-effective inject printed metamaterial to enhance the impedance bandwidth and realized the gain of a WLAN/WiMAX antenna. metamaterial structure can enhance impedance bandwidth as well as realized gain at the resonant frequency. The measured results show that the realized gain of the metamaterial loaded antenna gets improved by more than 0.6 dBi within the operating band and the impedance bandwidth is increased from 0.75 to 1.25 GHz. The proposed metamaterial loaded antenna has good radiation characteristics with an omnidirectional radiation pattern, so it can emerge as an excellent candidate for WLAN/WiMAX wireless communication.

Design and Analysis of Modified Split Ring Resonator Structured Multiband Antenna for WCDMA and WiMAX Applications

Abstract: A miniaturized slotted multiband antenna is presented. The antenna consists of a square Split Ring Resonator-shaped slot in the radiating patch. The split ring resonator structure-based antenna presents operational capability at 2.18, 2.56 and 3.52 GHz, respectively. The achieved return loss at the resonance frequencies are 21.38, 12.00 and 25.46 dB and the bandwidth of the proposed antenna are 2.51, 2.01 and 3.27% for respective frequencies. The standard low-loss cost-effective FR-4 laminates of 1.6 mm thickness substrate were used for the design. The proposed prototype antenna was fabricated and measured; the results show reliable agreement with the simulated results. The antenna possesses adequate gain values at all resonating frequencies. The reflection coefficient, radiation pattern and other antenna parameters are exhibiting quite satisfactory results, fulfilling the requirement for WCDMA and WiMAX applications.

A Brief Survey on Metamaterial Antennas: Its Importance and Challenges

Abstract: Metamaterials are opening a new way of refining the material science and related areas. Metamaterials broke the limitation of naturally occurring substances by artificially creating the desired material properties. This chapter presents a brief survey on metamaterials and their importance in the area of antenna design. Metamaterials in fractal antenna geometries, their applications in different areas are discussed. A brief discussion on metamaterial parameter extracting methods, different metamaterial geometries, challenges, and the way forward is given.

Metamaterial-inspired quintuple band printed patch antenna for dense communication networks

Abstract: A compact 15 mm × 15 mm multi-band metamaterial-inspiredprinted antenna, composed of a simple microstrip antenna and a metamaterial superstate, is developed to accommodate nowadays advanced wireless communication devices and networks, where multi-functional tasks are simultaneously performed in different frequency ranges efficiently. A quintuple homocentric circular split ring resonator is explicitly designed as a band enhancer metamaterial superstate. The metamaterial geometry and orientation associated with the antenna location and radiating are optimized for the greatest consequence, where the resonances electrically and magnetically couple with the antenna radiation, generating quintuple bands in the X band: 8–12 GHz. The main lobe directions indicate an excellent directional propagation. This metamaterial-inspired antenna was designed and fabricated using a low cost commercial FR4 substrate offering a good cost margin for potential mass production. Four of five bands have a gain greater than 6dBi, which can be improved by using low-loss substrate. The measured and simulated results are in good agreement.

Multibeam antennas with customized elevation angles based on near-field magnetic field coupling of metamaterials

Abstract: In this paper, we propose the design of multibeam antennas with customized elevation angles based on near-field magnetic field coupling of metamaterials. The antenna consists of a monopole feed and four identical metamaterial transmission-line (MTL) structures surrounding the feed. The MTL structure is composed of two pairs of broadside-coupled omega rings (BCORs) that are connected by two straight strip-lines. Under such a framework, magnetic fields within the near-field zone of the monopole feed can be coupled efficiently by the inner BCOR, converted to travelling waves along the double strip-lines, guided toward the outer end of the MTL structure, and radiated by the outer BCOR like a loop antenna. Due to travelling wave nature of the MTL structure, there is phase lag along the MTL structure and the radiation main lobes are tilted towards the outward direction. By arranging several MTL structures around the feed monopole, multi-beam directional radiation can be realized. More interestingly, by adjusting structural parameters and pitch angles of the MTL structures, elevation angle of the radiation main lobes can be customized. To validate the design, we simulated, fabricated and measured four prototypes with pitch angles 0°, 15°, 30° and 45°. Both the simulated and measured results verify the design and show that multiple-beam radiation with customized elevation angle can be obtained. This work provides an alternative method of designing multi-beam antennas and may find applications in communication, surveillance, etc.

Deflected beam pattern through reconfigurable metamaterial structure at 3.5 GHz for 5G applications

Abstract: In this paper, the reconfigurable metamaterial is proposed to deflect the radiated beam of the bow-tie antenna at a 5G band of 3.5 GHz. The split square resonator (SSR) is designed at a sub-6 GHz band and reconfigured to produce different refractive indices. For obtaining the desired deflection angles, 3 × 7 SSR unit cells with ON and OFF configurations are printed into the antenna substrate. This arrangement creates two metamaterial configurations with different refractive indices in the closeness of the radiating elements, thereby deflecting the main beam to the direction of high refractive index metamaterial. In the passive beam deflection antenna, the reconfigurable SSRs deflect the radiation beam of the antenna by angles of ±39° in E-plane at 3.5 GHz. Furthermore, the embedding of SSRs helps improve the gain by 2.4 and 2.3 dB for the positive and negative deflection angles, respectively. On the other hand, in the active beam deflection antenna, the reconfigurable SSRs based on real PIN diodes can deflect the antenna radiated beam by angles of ±36° in the E-plane. These reconfigurable antennas have the potential to be used in 5G beam deflection applications. Both passive and active metamaterial antennas are fabricated, and their performances are measured.

Miniaturized circular microstrip antenna designed with quasiperiodic sector metamaterials

Abstract: Miniaturized circular microstrip antennas (CMSAs) are designed by loading new quasiperiodic sector metamaterials in the substrate. The resonance performances of new antennas are numerically studied. One particular metamaterial CMSA is further experimentally demonstrated operating in the 3.5 GHz band. The practical new CMSA has a patch diameter of 20 mm fabricated on substrates with a dielectric constant of 3. The normalized diameter is hence only about 0.4λg (or 0.232λ0) which is beyond the 0.58λg limitation for a conventional CMSA. The bandwidth and antenna gain characteristics for the new antenna are also evaluated in experiments. Both are observed reasonably high for such a compact CMSA.

Size reduction of a conical horn antenna loaded by multi‐layer metamaterial lens

Abstract: In this paper, a conical horn antenna in the presence of a metamaterial lens in the X-band is introduced and fabricated. The annular metamaterial lens is located at the aperture of a shortened horn antenna, whose length is half the length of the corresponding optimum horn. The phase velocity in the metamaterial lens is more than the phase velocity along the axis of the antenna for the same propagation distance, so the phase distribution at the aperture of the antenna is uniform and the gain of the shortened horn antenna increases. Metamaterial cells are designed in the form of a printed circuit board that have easy to build and suitable cost. The design process is based on how the waves incident on the proposed metamaterial cell, and finally, by using the particle swarm optimisation (PSO) algorithm proper radiation characteristics in the desired frequency range can be achieved. The radiation characteristics of an antenna with a metamaterial lens are similar to that of an antenna with optimum length in the desired frequency band. The difference is that the weight and volume of these antennas are reduced, so they have better performance in satellite and radar systems.

Miniaturized Multiband Metamaterial Antennas With Dual-Band Isolation Enhancement

Abstract: We present electrically small, multi-band, metamaterial-inspired antennas with adequate radiation characteristics and isolation enhancement. The antenna element consists of a complementary split-ring resonator (CSRR) embedded in a small monopole that has a size of λ/8 × λ/10 at the lowest frequency band, while rectangular patches are placed underneath it to further improve the performance. The antenna operates at the 2.4-2.5/2.9-4.8/5.1-6.5 GHz frequency bands. Moreover, we propose a systematic, metamaterial-based approach in order to improve the isolation between two of these small, closely spaced antenna elements at the lowest and highest frequency bands. The proposed techniques reduce the coupling by up to 29 dB without increasing the size of the structure. In particular, the isolation enhancement at the highest frequency band of interest is remarkably wideband. The cable effect, which is a common concern during the measurements of small antennas, is examined as well. The proposed antennas are not only small but also densely packed and can be easily integrated with modern, compact communication devices with advanced functionality. Simulations along with experimental results validate the effectiveness of our design.

Metamaterial-Based Miniaturized DGS Antenna for wireless Applications

Abstract: Abstract In this article, metamaterial based miniaturized DGS (Defective Ground Structure) antenna is presented. Initially conventional antenna is designed for 2.4 GHz and by using DGS method, the same conventional antenna size is reduced upto 50% of initial design. But antenna gain down due to DGS in antenna structure. By using metamaterial as a reflector, the antenna gain can be enhanced. The antenna and metamaterial are designed on Rogers RT5880 and Teflon Ceramic TF-1/2 (ε r = 10.2, tanδ = 0.001) respectively. All simulation results are carried out by using EM simulator CST software and for the operating frequency of 2.415 GHz a gain of 6.28dB is observed.

Numerical Investigation of Frequency Reconfigurable Antenna with Liquid Metamaterials for X-band

Abstract: In this paper, a frequency reconfigurable liquid metamaterial microstrip-based radiating structure is proposed and it is an attempt toward achieving reconfiguration in liquid metamaterial-based microstrip radiating structures. Reconfigurable antenna design is superstrated with five liquid metamaterial layers based on a distilled water split-ring resonator. Superstrate layers give enhancement from 6.5 dB to 13.1 dB in gain of the proposed antenna. A patch is reconfigured through PIN diodes as RF switches. Switching ‘on’ and ‘off’ states of PIN diodes are used for reconfiguration of frequency and radiation patterns. Analysis in terms of reflection coefficient, gain (dBi), radiation pattern, bandwidth (BW), and half-power beamwidth (HPBW) is obtained in switch-off and switch-on state. The proposed design provides enhanced gain, reflection coefficient, and multiband characteristics in the 8-12 GHz range suitable for X-band satellite and radar applications. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited.

Gain Enhancement of Patch Antenna Using High Refractive Index Metamaterial-based Bi-convex Lens for Base Station Applications

Abstract: ABSTRACT In this paper, a high refractive index-based metamaterial Bi-convex lens superstrate for the gain enhancement of broadside radiating antennas like microstrip antennas is presented. Fundamentally, an effective HRI medium is created by the Single Ring Split Ring Resonator unit cells printed on an FR-4. By stacking the multiple layers of the superstrate, a virtual HRI-based equivalent Bi-convex lens is constructed to focus the incoming diverged beam from a patch antenna. A gain enhancement of 4.42 dB is achieved with the help of a 3-layer HRI-based Lens superstrate. The simulation and measurement results are also almost agreed on the same.