Artificial Magnetic Conductor Surface Research Articles

Enhancement of off-body communications with a low-SAR, high-gain multiband patch antenna designed with a quad-band artificial magnetic conductor

Abstract The increasing demand for wireless communication has emphasized the need for multiband antennas. This study presents a novel design for a multiband antenna with reduced specific absorption rate (SAR), high gain, and improved front-to-back ratio (FBR) achieved through the integration with a 4 × 4 artificial magnetic conductor (AMC) surface. The proposed antenna covers a wide range of wireless frequency bands, including Industrial, Scientific, and Medical, Wireless Local Area Network, Worldwide Interoperability for Microwave Access, Wi-Fi 6E, and 7, with resonating frequencies at 2.4, 3.2, 5.5, 7.5, and 10 GHz. The AMC unit cell creates four zero-degree reflection phases with double negative properties at 2.5, 3.8, 5.5, and 7.5 GHz. The compact design measures 0.23λ0 × 0.296λ0 × 0.0128λ0 and placed 0.104λ0 above an AMC surface of size 0.512λ0 × 0.512λ0 × 0.1296λ0. This structure enhances the gain by up to 8.55dBi at 6.01 GHz. The proposed antenna has −10 dB impedance bandwidth for these corresponding frequencies viz 2.34–2.43 GHz (3.77%), 2.81–3.83 GHz (30.72%), 4.82–6.21 GHz (25.20%), 7–7.65 GHz (8.87%), and 8.06–10.31 GHz (24.5%). An overall average percentage reduction value of SAR taken at these frequencies has been found to be 96.11% with AMC structure. The antenna sample was successfully fabricated, and the experimental results have been found to match well with the simulation results. This integrated design offers a promising solution for wearable off-body communication devices.

A dual-band low-profile Fabry–Perot resonator antenna with single partially reflecting surface

ABSTRACTThis paper presents a novel design for a low-profile Fabry–Perot resonator antenna (FPRA) that operates at two distinct frequency bands using a single partially reflecting surface (PRS). The PRS is composed of two different types of unit cells arranged in a staggered fashion. These unit cells are comprised of double-sided complementary structures, including a square patch with a square aperture and a circular ring with a circular ring slot. To reduce the overall profile of the antenna, an artificial magnetic conductor (AMC) surface is utilized as the reflection plane. The proposed design employs a dual-band slotted patch antenna as the primary source. The overall dimensions of the FPRA are 91 mm×91 mm×5.54 mm. The performance of the prototype antenna is validated through measurement, demonstrating peak gains of 14.1 and 16.1 dBi at frequencies of 6.65 and 12.05 GHz, respectively. Additionally, the antenna exhibits −10 dB impedance bandwidths of 6.5–6.8 GHz and 12.15–12.23 GHz at the two frequency bands.

Ferrite-Loaded Inverted Microstrip Line-Based Artificial Magnetic Conductor for the Magnetic Shielding Applications of a Wireless Power Transfer System

In this paper, we propose a ferrite-loaded inverted microstrip line (IML)-based artificial magnetic conductor (AMC) with a novel design that can provide complete magnetic shielding at the backside of the transmitting (Tx) coil while slightly improving the power transfer efficiency (PTE) of a wireless power transfer system (WPTS). The target frequency of the WPTS application is approximately 6.78 MHz. In the proposed design, the AMC is placed behind the Tx coil, and its magnetic shielding capability and PTE performance were verified through simulations and measurements. The size of the proposed AMC is 528 × 528 × 6.6 mm3. The measurement results verified that, compared with the Tx coil without an AMC surface, the proposed ferrite-loaded IML-based AMC can provide complete magnetic shielding while improving the PTE of the WPTS by approximately 8.05%.

Metasurface-Assisted Broadband Compact Dual-Polarized Dipole Antenna for RF Energy Harvesting

In this letter, a low-cost dual-polarized broadband dipole antenna is studied for RF energy harvesting applications. The 2×2 antennas are arranged with a rotational symmetry over an Artificial Magnetic Conductor (AMC) surface to capture the ambient RF energy from both the Horizontal (H) and Vertical (V) polarizations in a multiple input multiple output (MIMO) environment. The antenna is then integrated with a single-series rectifier circuit network in a series fashion. In the final step, an LED is connected as the common load to demonstrate the process of capturing the RF energy, thereby glowing the LED.

A monopole antenna with cotton fabric material for wearable applications

A monopole antenna operated at 2.45 GHz and embedded with artificial magnetic conductor (AMC) for wearable communication systems is investigated in this article. The proposed antenna is composed of a metalized loop radiator with a coplanar waveguide microstrip feedline which is affixed on a cotton fabric material substrate. As well, a cotton-based AMC surface is utilized to eliminate the body’s absorbed radiation and enhance the gain of the antenna. It is composed of 5 × 5 array unit cells etched with I-shaped slots. Using this configuration, simulations show that the specific absorption rate (SAR) level was significantly reduced. Considering flat and rounded body parts, it was found that the SAR values averaged over 10 g at a distance of 1 mm away from the tissues model were only 0.18 W/kg and 0.371 W/kg, respectively. Additionally, the antenna gain was improved up to 7.2 dBi with an average radiation efficiency of 72%. Detailed analysis with experimental measurements of the cotton-based antenna for different operation scenarios is introduced. The measured data show a good correlation with the electromagnetic simulation results.

Low‐profile wideband four‐element MIMO array using Giuseppe Peano AMC surface with improved efficiency and isolation for WLAN systems

AbstractA low profile four‐element multiple‐input multiple‐output (MIMO) array of printed dipole antenna (PDA) backed by second iteration of Giuseppe Peano fractal artificial magnetic conductor (AMC) is introduced for broadband wireless communications. First, a suggested PDA with a pair of microstrip E‐shaped dipoles excited by an E‐shaped microstrip feedline is used to expand the bandwidth in the range of 5.47–6.92 GHz (S11 ≤ −10 dB). Then, the suggested 4 × 4 Giuseppe Peano fractal AMC reflector is loaded into the PDA to exhibit −10 dB measured impedance bandwidth from 4.21 to 7.06 GHz (50.61%) for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The proposed four‐element MIMO array loaded by 6 × 6 AMC reflector with diverse polarizations of elements introduces a low profile wideband structure. The measured results of four elements include the broad bandwidths from 4.3 to 7.05 GHz with enhanced gains (more than 8 dBi) and high efficiencies. The high isolations between the four elements with diverse polarizations are obtained larger than 26.5 dB and they reach 66 dB over the operating bandwidth for MIMO systems. The suggested PDA with AMC compared to the PDA without AMC exhibits a size reduction of 51.33%, enhanced radiation efficiency up to 94%, and excellent impedance matching with uni‐directional radiation patterns.

Improving the Performance of Antenna-on-Chip by Effectively Illuminating the Artificial Magnetic Conductors Through Coupling Enhancement Structures

An antenna-on-chip (AoC) suffers from low radiation efficiency and gain because of the highly conductive silicon substrate used in standard complementary metal–oxide–semiconductor (CMOS) processes. Placing an artificial magnetic conductor (AMC) surface underneath the AoC not only isolates the antenna from the lossy substrate but also boosts its performance through in-phase reflection. Ideally, the AMC, which has a periodic structure, should be infinite in size, but practical chip sizes limit its dimensions. The gain of an AMC-backed AoC shows a positive correlation with the AMC lateral area. However, in the ultrathin stack-up of standard CMOS processes, the AMC cannot be irradiated uniformly by the antenna because of the physical illumination issue, so the AoC gain does not increase with the AMC area after the initial increase. To improve the illumination of the AMC by an AoC, this work introduces coupling enhancement structures (CES) that employ the available metal layers of the stack-up. The proposed AMC-backed AoC with CES demonstrates a gain of 9.8 dBi and radiation efficiency of 71% at 94 GHz, which are improvements of 4.3 dB in gain and 23% in radiation efficiency, respectively, compared to an AoC backed by a conventional AMC.

A compact triband antenna using artificial magnetic conductor for wireless body area network communicationsFront

The proliferation of the Internet of Things devices and advancements in wireless communication have fostered the growth of Wireless Body Area Networks (WBAN). This research provides a triband antenna supported by a 4 × 4 Artificial Magnetic Conductor (AMC) array surface that has a low Specific Absorption Rate (SAR), a high Front to Back Ratio (FBR), and increased gain for use in wearable devices. For WBAN communications, the proposed antenna operates in the Industrial, Scientific, and Medical (2.4 GHz) band, the C (3.7–4.2 GHz), and the Wi-Fi 6E (5.925–7.125 GHz) bands. The dual-band AMC unit cell exhibits Double-Negative and angular stability behaviour at 2.45 GHz and 6.5 GHz. AMC-backed antenna achieved multiband functionality by incorporating slots into the unit cell and a defective ground structure into the antenna. The antenna was positioned 0.139λ0 above the AMC surface, which measured 0.556λ0 × 0.556λ0 × 0.013λ0 (at 2.45 GHz). The antenna exhibited good gain and return loss variations when mounted on curved surfaces. The proposed integrated design yielded substantial enhancements, as evidenced by the increase of 8.2 dBi in maximum gain, 25.2 dB in FBR, and over 93% in total efficiency. The AMC-backed antenna’s − 10 dB impedance bandwidth is 18.4%, 21.2%, and 22.3%, with corresponding frequency ranges of 2.25–2.66 GHz, 3.66–4.53 GHz, and 5.9–7.35 GHz. Additionally, the AMC surface showed an average reduction in SAR of 93.22%. Vector Network Analyzer and Anechoic chamber measurements proved simulation accuracy. As a result, it is strongly recommended that the integrated antenna design be acknowledged in WBAN communications.

Broadband Printed Tapered Slot Antenna Fed by CPW Fulfilled with Planar Artificial Magnetic Conductor for X-Band Operation

A low-profile printed slot antenna (PSA) backed by broadband planar artificial magnetic conductor (AMC) is introduced in this study. Firstly, a suggested PSA with the radiating tapered slots excited by coplanar-waveguide (CPW) is used to expand the bandwidth in the measured range of 9-11 GHz (S11≤ -10 dB). Then, the suggested planar AMC surface as the ground plane of the antenna is inserted into the PSA to gain improved radiation efficiency. The realized result from the PSA with the 9×9 planar AMC array exhibits -10 dB measured impedance bandwidth from 6.63 to 13.73 GHz (70%). The suggested PSA with AMC compared to the PSA without AMC exhibits a size reduction of 60%, enhanced bandwidth of 50%, and excellent impedance matching with a minimum value of almost -40 dB. The novel AMC unit cell is realized to operate at 10.14 GHz with an AMC bandwidth of 8-12.35 GHz (43.1%) for X-band operation. Besides, by loading a periodic AMC unit cells into PSA, a high gain of more than 11 dBi with uni-directional radiation patterns is achieved.

AMC-Loaded Low-Profile Broadband Printed 2×2 Array With Gain and Isolation Enhancement Using Equivalent Circuit Model for Wireless Systems

A 2×2 array of printed antenna loaded by planar Giuseppe Peano artificial magnetic conductor (AMC) is presented for vehicular wireless systems. The four-element of the proposed array by utilizing diverse polarized directions of the printed dipoles with a 5×5 AMC reflector achieves a wideband antenna with enhanced properties. It shows the measured S-parameters of the wide bandwidths from 3.30 to 6.02 GHz with increased stable gains and efficiencies (more than 90%) for all elements. Moreover, the appropriate isolation of greater than 30 dB between the elements is achieved. The proposed design of the printed dipoles includes T-shaped microstrip dipoles and a feedline system as a T-shape to broaden the bandwidth in 4.7-6.02 GHz (S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> ≤ -10 dB). By utilizing the 3×3 Giuseppe Peano AMC reflector into the one element of the printed dipole, enhanced radiation efficiency and -10 dB measured bandwidth from 3.26 to 6.02 GHz (60%) is achieved for vehicular wireless systems. The proposed design with AMC with respect to the antenna without AMC indicates a reduced size of 70%, increased gain up to 8.4 dBi, and uni-directional radiation patterns. The new AMC unit cell is configured by the Giuseppe Peano design to resonate at 5.36 GHz in 4.27-6.34 GHz (39%). Finally, the suggested equivalent transmission line model of the 2×2 array with AMC surface is introduced with a suitable agreement between the results of reflection coefficients.

AMC-Based Low-Profile Dual-Band Slotted Patch Antenna for IoT Devices in the Healthcare System

An artificial magnetic conductor (AMC)-based patch antenna with a low profile is developed for wireless devices in IoT-based healthcare systems. The proposed antenna comprises two pairs of circular-shaped patches with circular-shaped slots and a dual-band 4 × 4 array of AMC reflectors with two zero-degree reflection responses to enhance the antenna's radiation performance. For the 2.45 GHz ISM and 5.4 GHz WLAN bands, the patch antenna has dimensions of 0.44λ0 × 0.52λ0 × 0.013λ0, with partial ground structures to improve radiation characteristics. Following that, a unique dual-band symmetrical AMC unit cell with dimensions of 22 × 22 × 1.6 mm3 is developed. There is a gap of 15 mm between the antenna and the AMC surface. The antenna is supported by a 4 × 4 AMC array that has a total dimension of 0.72λ0 × 0.72λ0 × 0.15λ0. The reflection coefficient values of less than − 10 dB in the 1.7–2.5 and 5.1–5.6 GHz bands, with a bandwidth percentage of 38 and 9.3%, respectively. The antenna's gains were 7.2 and 4 dBi inside the bands. Furthermore, the Specific Absorption Rate (SAR) value did not match the WHO's safety and health guidelines. The issue was solved by including an AMC surface in the proposed antenna. At 2.45 and 5.4 GHz, SAR values of 0.58 and 1.04 W/Kg were measured. Vector network analyser and anechoic chamber were used to test the performance of antenna and AMC surface prototypes. There is a substantial agreement among measured and simulated parameters of an antenna. Consequently, the developed antenna combination with the AMC structure is suited for wireless devices in ISM and WLAN bands, often used in IoT-based healthcare systems.

A wideband frequency reconfigurable antenna with improved gain

AbstractA wideband frequency reconfigurable antenna based on active artificial magnetic conductor (AAMC) surface is proposed with improved gain. The AAMC element consists of a composite polygon‐rectangle‐ring with five patches and a cross‐strip inside. A reverse‐bias varactor is inserted between the ring and ground plane to make the in‐phase reflection frequency bands adjustable. A dipole is placed above the AAMC surface which is composed of 5 × 5 unit cells. The measured results show that the reconfigurable frequency ranges from 1.64 to 4.16 GHz while maintaining the radiation patterns stable. Moreover, the peak gain reaches 10.65 dBi at 3.5 GHz.

Multiple Stacks of Rotated Metal Strip Gratings for High-Gain Bandwidth Enhancement and Gain Control of Overlying Dipoles—Analysis by Asymptotic Strips Boundary Conditions

As an amenable and efficient alternative to formulaically cumbersome and computationally demanding full-wave modal approaches, the herein analytical method uses the asymptotic strips boundary conditions along with classical vector potentials and coordinate transformations to treat multiple stacks of rotated metal strip gratings with general dielectric layers between them. For all cases, either with conducting terminal planes on just one side, on both, or none at all, solutions to plane-wave illuminated and/or modal dispersion eigenvalue problems are all obtainable. With the additional degrees of parametric freedom afforded by the angles of rotation between gratings, not only may wider ranges of special properties such as artificial surface impedances be achieved at fixed frequencies, they can also be reconfigured by the rotation of the gratings, being a simple, single-sweep-type mechanical motion, as opposed to electronic means entailing complex networks and intricate circuitries. In addition to the presentation of the formulation details and validation results, this article demonstrates the importance of multiple stacks of rotated strip gratings in widening the otherwise compromised bandwidths of artificial magnetic conductor (AMC) surface characteristics subjected to strict reflection-phase criterion for preserving high maximal broadside gains of overlying prostrate dipole antennas as well as attaining full-range gain control. Prototypes are manufactured and measured with a good agreement with theory.

Analysis and Design of Wideband Low-RCS Fabry–Perot Antennas With Reduced Profile

In this article, two incomplete partially reflective surface (PRS)-based Fabry–Perot (F-P) antennas each with a high gain, wideband low radar cross section (RCS), and reduced profile are proposed. The reductions of the antenna profiles and RCS are realized based on artificial magnetic conductor (AMC) surfaces and the phase cancellation, respectively. In the first design, two AMC surfaces are placed around the radiation patch and above the PRS. The thickness of the F-P cavity is reduced by half due to the zero-phase reflection of the lower AMC surface around the radiation patch. The income waves are partly reflected by the upper AMC surface above the PRS with zero reflection phase and partly penetrate the PRS and then reflected by the lower AMC surface also with zero reflection phase. The reflected EM waves from the bottom AMC surface travel another distance of quarter wavelength in the upward direction making the total electrical path traveled be half wavelength, thereby causing a phase shift of 180° with the reflected waves from the upper AMC surface, and thus resulting in a wideband RCS reduction. For the second design, another AMC surface is placed below the PRS. On one hand, the middle and lower AMC surfaces have the same reflection phases and then an F-P cavity with a subwavelength thickness is generated. On the other hand, the phase difference between the upper and lower AMC surfaces is also designed as 180°, which is used to suppress the total backward RCS. The two F-P antennas are both fabricated and measured. Measured results validate their reflection, radiation, and scattering performance well. To the best of our knowledge, this work is the first design, which integrates the physical (thin F-P cavity), radiation (gain enhancement), and scattering (broadband RCS reduction) performance of the F-P antenna.

Design and Simulation of Miniaturization of Triangular Shape Dielectric Resonator Antenna Using AMC Surface for 5G Applications

A Dielectric Resonator Antenna (DRA) is a radio antenna. It is built up of ceramic material into blocks of various forms and is generally suitable at frequencies larger than 1 GHz (microwave frequencies and higher than microwave frequencies). Using this Dielectric Resonator Antenna, the operating frequency is achieved at 4.8GHz for 5G applications like IOT (Internet of Things), AI (Artificial Intelligence). Here, artificial magnetic conductor (AMC) surface is used to miniaturize a triangular shaped Dielectric Resonator Antenna (DRA). There are nine tiny copper patches forms the Artificial Magnetic Conductor (AMC) surface having gap of 1.5mm between the patches. AMC is installed on FR4 substrate which has dielectric constant as 4.4. On the AMC surface, a Dielectric Resonator (DR) of dielectric constant 2.2 is placed. The surface of the Artificial Magnetic Conductor is shorted with ground metal using tiny metallic vias. Antenna characteristics such as antenna gain, resonant frequency, and efficiency will not be affected due to the usage of Dielectric Resonator. As a result, the overall volume of DRA is significantly diminishing. There are three primary aspects in this design: (a) Impedance matching using a Parasitic Metallic Strip (b) Design miniaturisation with an AMC surface (c) Simple microstrip line Feeding. Overall volume of Dielectric Resonator Antenna size reduced by 85%. In addition, when compared to the original Dielectric Resonator Antenna without the surface of Artificial Magnetic Conductor, the ground surface is lowered by 15.5 percent.

Gain enhancement of a wideband rectangular ring monopole millimeter‐wave antenna using artificial magnetic conductor structure

In this article, the design and development of an artificial magnetic conductor (AMC)-backed compact wideband rectangular ring monopole antenna with high gain is proposed for millimeter-wave (mmWave) applications. It is constructed through stacking a coplanar waveguide (CPW)-fed rectangular ring patch monopole antenna over a square modified AMC reflector surface of 5 × 5 periodic unit cells. Primarily, the ring monopole antenna of size 1.21λ0 × 1.21λ0 × 0.023λ0 (at 28 GHz) is designed and exhibits wide impedance bandwidth of 30.64% (25.98–35.38 GHz, 9.4 GHz), a peak gain of 4.86 dBi and front-to-back ratio (FBR) up to 5.2 dB. To enhance the radiation performance of the monopole antenna, a periodic lattice of 5 × 5 unit cells modified square AMC surface with a gap of 0.84λ0 is proposed and it functioned as reflector which enhances the peak gain of about ~77% and it contributes FBR up to 15 dB. Measured results of the modified square AMC-backed monopole antenna reveal a wide impedance bandwidth of 31.27% (25.90–35.50 GHz, 9.6 GHz), a peak gain of 8.59 dBi, and stable radiation characteristics.

Analysis of 2 × 2 MIMO array loaded by artificial magnetic conductor with improved gain, isolation, and bandwidth using equivalent transmission line model for indoor wireless base station

A low profile printed dipole antenna (PDA) backed by broadband Giuseppe Peano fractal artificial magnetic conductor (AMC) is introduced for wireless communications. First, a suggested PDA with a pair of microstrip dipoles excited by an E-shaped microstrip feedline is used to expand the bandwidth in the range of 5.96–7.04 GHz (S11 ≤ −10 dB). Then, the suggested Giuseppe Peano fractal AMC surface as a reflector of the antenna is inserted into the PDA to gain improved radiation efficiency. The PDA with the 6 × 6 Giuseppe Peano AMC array exhibits −10 dB measured impedance bandwidth of 4.95–7.05 GHz (35%) for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The suggested PDA with AMC compared to the PDA without AMC exhibits a size reduction of 38%, enhanced gain up to 8.2 dBi, and excellent impedance matching (at least −20 dB) with directional radiation patterns. The novel AMC unit cell is realized based on the Giuseppe Peano fractal patch to operate at 6.10 GHz with an AMC bandwidth of 5.15–7.10 GHz (32%). Besides, by loading 12 × 12 AMC reflector into the four-element array of PDA, low profile wideband structure with enhanced radiation properties are achieved. The measured results show the broad bandwidths of 5–7 GHz for all elements with enhanced gains and good isolations between the elements (more than 24 dB) for multiple-input multiple-output (MIMO) systems.

Artificial magnetic conductor‐backed dual‐band shared‐aperture antenna array for base station applications

A low-profile dual-band dual-polarized base station antenna array is proposed. The dual-band array is backed by an artificial magnetic conductor (AMC) surface. The AMC achieves profile reduction to 0.159 λL0 in the low band (LB), but it acts as a bandpass metasurface in the high band (HB). The nested design of AMC unit cell creates two out-of-phase induced currents with lower intensities, enabling suppression and cancelation of HB scattered fields. The back cavities establish clear and independent radiating environments for the LB and HB antennas. They aid in further radiation pattern restoration and antenna profile reduction. The proposed antenna array was fabricated and experimentally measured. The simulated and measured results are presented. The operating principles of the proposed AMC and back cavities are also investigated.

High‐isolated broadband eight‐element linear multi‐input multi‐output array over artificial magnetic surface for wireless and sub‐6 GHz 5G communications

SummaryA low‐profile eight‐element printed dipole antenna (PDA) array backed by broadband rhomboid artificial magnetic conductor (AMC) is introduced for wireless communication systems. By loading a 4 × 27 AMC reflector into the eight‐element array of PDA, a low‐profile wideband structure with enhanced radiation properties is achieved. The measured S parameters show the broad bandwidth from 4.75 to 7.05 GHz in C‐band with enhanced gains of eight elements (more than 8 dBi) and the suitable isolation between the array elements of more than 23 dB for multi‐input multi‐output (MIMO) systems. The suggested PDA with a pair of the microstrip meandered folded poles excited by an E‐shaped microstrip feedline expands the bandwidth in the range of 5.85–6.95 GHz (S11 ≤ −10 dB). The novel AMC unit cell is realized based on the recognized method as rhomboid coupled parasitic patches. The rhomboid AMC design operates at 6.26 GHz with an AMC bandwidth of 5.20–7.24 GHz (32.8%). Then, the suggested rhomboid AMC surface as a reflector of the antenna is inserted into the PDA to exhibit −10 dB measured impedance bandwidth from 4.94 to 6.93 GHz (more than 33%) for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The suggested PDA with AMC compared to the PDA without AMC exhibits a size reduction of 34%, enhanced gain up to 8 dBi, and excellent impedance matching (at least −20 dB) with directional radiation patterns.

Radiation Properties Improvement of 1 × 4 Array of Wideband Printed Antenna Supported by AMC Surface for Vehicular MIMO Systems

AbstractA 1 × 4 array of printed dipole antenna (PDA) with a broadband rhomboid artificial magnetic conductor (AMC) is introduced. A suggested PDA using a pair of microstrip dipoles with unequal arms excited by a T‐shaped microstrip feedline expands the bandwidth in the measured range of 5.27–6.74 GHz. Then, the suggested 3 × 3 AMC reflector is inserted into the PDA to exhibit −10 dB measured impedance bandwidth from 4.20 to 7.11 GHz for WLAN and WiMAX applications. The suggested PDA with AMC compared to the PDA without AMC exhibits a size reduction of 46.72%, enhanced gain up to 8.4 dBi, and excellent impedance matching with unidirectional radiation patterns. The novel AMC unit cell operates at 6.20 GHz with an AMC bandwidth of 5.09–7.21 GHz. Also, by loading a 3 × 8 AMC periodic array on a FR4 substrate with 3 mm thickness underneath the four‐element array of PDA with a gap distance of 3 mm, a low‐profile wideband structure with enhanced radiation properties is achieved. The measured S‐parameters show the broad bandwidth from 4.26 to 7.28 GHz with enhanced gains and efficiencies of all elements. Besides, the suitable isolation between the array elements of more than 30 dB for multiple‐input multiple‐output (MIMO) systems is achieved by applying various polarized directions of PDAs and loading the 3 × 8 periodic AMC reflector. Finally, the proposed MIMO design introduces remarkable advantages of good size reduction and bandwidth enhancement, low‐profile antenna with high stable gain, high efficiency and large isolation, and unidirectional radiation patterns with reduced backside direction.