Multiband Antenna 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.

Low-Loss Paper-Substrate Triple-Band-Frequency Reconfigurable Microstrip Antenna for Sub-7 GHz Applications.

In this paper, a low-cost resin-coated commercial-photo-paper substrate is used to design a printed reconfigurable multiband antenna. The two PIN diodes are used mainly to redistribute the surface current that provides reconfigurable properties to the proposed antenna. The antenna size of 40 mm × 40 mm × 0.44 mm with a partial ground, covers wireless and mobile bands ranging from 1.91 GHz to 6.75 GHz. The parametric analysis is performed to achieve optimized design parameters of the antenna. The U-shaped and C-shaped emitters are meant to function at 2.4 GHz and 5.9 GHz, respectively, while the primary emitter is designed to operate at 3.5 GHz. The proposed antenna achieved peak gain and radiation efficiency of 3.4 dBi and 90%, respectively. Simulated and measured results of the reflection coefficient, radiation pattern, gain, and efficiency show that the antenna design is in favorable agreement. Since the proposed antenna achieved wideband (1.91-6.75 GHz) using PIN diode configuration, using this technique the need for numerous electronic components to provide multiband frequency is avoided.

Design of Multiband Microstrip Patch Antenna for Satellite Applications

In the fields of satellite communication and aerospace, the multiband microstrip patch antenna has emerged as a game-changing technology that meets crucial needs of the contemporary day. The use of this antenna is essential as the need for faster data transfer rates and wider coverage keeps rising. In this paper, a microstrip patch antenna is designed for operating into Ku band for satellite communication and aerospace communication. The antenna is operating at 15.8 GHz and in the Ku band. The antenna is designed with slot configurations on the patch, forming an 'H' shape, and on the feed, resembling a 'U' shape. The integration of these slot structures enhances the antenna's gain, achieving 7.44 dB with useful bandwidth of 3.2 GHz. Furthermore, the antenna exhibits ultrawide band properties, extending its versatility and potential applications.

Multi-Band Antenna Design by Reshaping Surface Currents of Higher Order Mode Using CMA Method

A multi-band antenna design by surface current reshaping of higher-order modes is presented. This method utilizes characteristic mode analysis to modify the conventional circular patch antenna in accordance with the surface current distribution of higher-order modes at the L5, S, and L1 bands using CMA. The antenna is evaluated up to four modes inducing fundamental mode. The S and L1 bands are obtained by exciting reshaped higher-order modes, while the L5 lower band is obtained by exciting the fundamental mode using full-wave analysis with 50 Ω coaxial feed. The measurement results are very similar to simulated antenna results. The measured operating frequencies of the proposed antenna are 1177.00 MHz (L5-band), 1575.00 (L1-band) MHz, and 2497.50 (S-band) MHz with associated impedance bandwidth (S11 ≤ −10 dB) are 25.30 MHz (1164.40–1189.70 MHz), 65.30 MHz (1535.50–1600.80 MHz), and 48.60 MHz (2464.10–2512.70 MHz) having desired gain with hemispherical radiation characteristics. These bands are used in Global Positioning Services (GPS) and in Indian Regional Navigation Satellite System (IRNSS) applications.

CSRR loaded multiband THz MIMO antenna for nano-communications and bio-sensing applications

In this paper, a multiband THz Multi-Input Multi-Output (MIMO) antenna is designed with dimensions of 80×100×10.8μm³. The antenna is made-up on a gold-plated Arlon AD410 substrate with a relative permittivity of 4.1.It operates at three resonant frequencies, namely 1.45THz, 2.25THz, and 3.25THz, achieved through the integration of Complementary Split-Ring Resonator (CSRR) and Substrate Integrated Waveguide (SIW) technologies. The two-element MIMO configuration of the antenna ensures exceptional performance, offering high throughput with data rates of 25.23Gbps for the Quadrature Phase Shift Keying (QPSK) scheme and 56.68Gbps for the 16-Quadrature Amplitude Modulation (QAM) scheme. It also exhibits remarkable channel capacity, approximately 8.2bps/Hz at Signal-to-Noise Ratio (SNR) = 20dB, surpassing the capabilities of single-element antennas. Moreover, it demonstrates excellent diversity performance for judging the MIMO antenna performance. This is evident through the following key metrics: Envelope Correlation Coefficient (ECC) < 0.02, indicating that less than 1 % of power is transferred from the excited antenna to the second 50Ω terminated antenna when antenna-1 is excited; Directive Gain (DG) >9.95dB; Total Active Reflection Coefficient (TARC) < -10dB, ensuring that a minimum of 90 % of the power is delivered to the patch port; and Channel Capacity Loss (CCL) < 0.35 bits/sec/Hz, guaranteeing reliable wireless communication. The antenna boasts peak gains of 3.83dBi, 4.06dBi, and 6.82dBi at 1.45THz, 2.25THz, and 3.25THz, respectively, along with a radiation efficiency of approximately 37, 58, and 51 % at the corresponding frequencies. Notably, the first two bands (1.34-1.51THz and 2.20-2.28THz) exhibit narrow bandwidths with quality factors above 80, making them particularly suitable for sensing applications in biomedical. Band-1 offers an average sensitivity of 3222.22 GHz/RIU and an FOM of 17.89, while Band-2 provides an average sensitivity of 2578.68 GHz/RIU and an FOM of 14.38. These characteristics make it well-suited for near-field Nano-communications and sensing applications.

Dual-wideband radiating surface using interleaved electric and magnetic currents: Underlying physics and experimental verification

Unlike popular multiband antenna array radiation based on either electric or magnetic surface currents, the use of mutually interleaved and tightly coupled electric and magnetic currents results in an aperture-reuse space-efficient multiband radiating surface for highly integrated antenna-frontend architecture and spatial power combining design scenarios. In this work, slot and dipole modes corresponding to magnetic and electric currents are effectively interleaved and excited in a surface to develop a space-efficient dual-wideband aperture-shared radiating surface. In this case, due to an effective reuse of the antenna aperture over both frequency bands, a high aperture-reuse efficiency is achieved. First, we devise a planar magneto-electric (ME)-dipole-alike antenna and analyze it in both the frequency and time domain. The antenna is then studied by the characteristic mode theory and the findings are validated using full-wave simulations. The developed planar ME-dipole-alike antenna is used to realize a dual-wideband radiating surface in which electric and magnetic currents are mutually coupled and interlaced, which is excited by properly oriented and distributed sources on the antenna's surface. Eventually, a highly isolated dual-wideband prototype was developed and fabricated using a cost-effective multi-layer Printed Circuit Board (PCB) process that operates in the Ku-band with both impedance and gain bandwidth of approximately 42% and in the Ka-band with respective impedance and gain bandwidth of 29% and 16.32%.

Design of Multi-band Microstrip Antenna with Rectangular Patch for 2.3 GHz, 2.4 GHz, and 3.5 GHz Frequencies

Cellular developments encourage the integration of both 4G, Wi-Fi, and 5G network technologies into one device; an antenna is a tool that can be used to support the integration of these networks. A microstrip antenna is an antenna that is small, light, thin, easy to fabricate, and can be used in long ranges. In this paper, a microstrip antenna is designed on a printed circuit board (PCB) with a permittivity of 4.3 and a thickness of 1.6 mm. This research aims to design a microstrip antenna that is capable of working on 4G (2.3 GHz), Wi-Fi (2.4 GHz), and 5G 3.5 GHZ) frequencies in one antenna. The microstrip antenna is designed on a Printed Circuit Board (PCB) with a permittivity of 4.3 and a thickness of 1.6 mm, rectangular shaped patches, and each patch is connected using a bridging method. Next, the antenna is simulated using CST Suite 2021 software. Simulation results at frequencies of 2.3 GHz, 2.4 GHz, and 3.5 GHz produce return losses of -23.70, -22.87, and -20.60, VSWR values of 1, respectively. .13, 1.15, and 1.20, the bandwidth values are 6.27%, 3.84%, and 5.84%, respectively, and the gain values are 4.69 dBi, 8.53 dBi, and 3.49 dBi.

Joint Microwave and Millimeter-Wave Antenna Design for UAV-Enabled Communications

Wireless communications aided by unmanned aerial vehicles (UAVs) have emerged as a promising technology for serving numerous terminal devices of the Internet of Things (IoT). To support such a broad range of emerging applications, millimeter-wave (mm-Wave) is an effective solution because it has the characteristics of high transmission efficiency, wide frequency band, and very low latency. Meanwhile, a UAV-assisted communication system also requires a global positioning system (GPS) reception (1.575 GHz) and ground control unit (2.4 GHz). This paper investigates a highly integrated multi-band antenna design to operate at the microwave (μ-Wave) and mm-Wave bands for robust and flexible UAV communications. Each antenna operating band utilizes the technology of a substrate-integrated waveguide (SIW) cavity-backed antenna. By strategically engineering an mm-Wave antenna into a 2.4 GHz band antenna to share the aperture, besides showing high aperture reuse efficiency with a large frequency ratio, the proposed antenna has also maintained the geometrical advantages of compactness, planar configuration, and ease of integration with other circuits. Furthermore, the proposed antenna can provide flexible radiation patterns with upper/lower-space signal coverage according to the mission demands of the UAV. Experimental results of the prototype show that the antenna can fully cover the 1.575 GHz, 2.4 GHz, and fifth-generation (5G) mm-Wave bands of n257, n258, and n261. Multiple bands and stable radiation characteristics indicate the proposed antenna's suitability for deploying a UAV-supported wireless network.

Topological acoustic waveguide with high-precision internal-mode-induced multiband

In this paper, we propose a topological acoustic waveguide which can transmit high-precision and multiband sound energy with backscattering suppression and no energy loss. It is a kind of acoustic waveguide with spatial lattice uniformity without destroying lattice position. This acoustic structure is obtained by integrating two kinds of multi-stage resonators arranged in a triangular lattice pattern in the air environment. On one hand, the introduction of internal modes greatly improves the transmission accuracy of topological acoustic waveguide compared with the Bragg scattering alone under the same overall structure size. On the other hand, it greatly improves the utilization rate of the internal space of the structure and makes full use of the multi-modal in structure to construct more sound transmission bands. After introducing the rotational scattering mechanism, the numerical and experimental results show that up to seven high-precision acoustic transmission channels with backscattering suppression and no energy loss below 14 kHz are obtained along the sonic crystal interface with different topological states in this topological acoustic waveguide. This research paves the way for engineering applications of high-precision acoustic transmission, multi-band acoustic antennas, acoustic logic control, covert sound transmission and other multifunctional acoustic devices.

A Multi-Band Circularly Polarized-Shared Aperture Antenna for Space Applications at S and X Bands

In this article, a compact multiband antenna design and analysis is presented with a view of ensuring efficient uplink/downlink communications at the same time from a single antenna for CubeSat applications. This design shares the aperture of an S-band slot antenna to accommodate a square patch antenna operating in the X-band. Shared aperture antennas, along with an air gap and dielectric loading, provided good gain in both frequency bands. The S-band patch had an S11 = −10 dB bandwidth of 30 MHz (2013–2043 MHz, 1.5%), and the X-band antenna demonstrated a bandwidth of 210 MHz (8320–8530 MHz, 2.5%). The Axial Ratio (&lt;3 dB) bandwidth of the slot antenna in the S-band is 7 MHz (2013–2020 MHz, 0.35%), and it is 67 MHz (8433–8500 MHz, 0.8%) in the case of patch antenna in the X-band. While the maximum gain in the S-band reached 7.7 dBic, in the X-band, the peak gain was 12.8 dBic. This performance comparison study shows that the antenna is advantageous in terms of high gain, maintains circular polarization over a wideband, and can replace two antennas needed in CubeSats for uplink/downlink, which essentially saves space.

Design and performance analysis of 8‐port multi‐service quad‐band MIMO antenna for automotive communication

AbstractIn this paper, a low profile compact 8‐port multiband antenna with polarization diversity principle for automotive communication is proposed. The geometric of the proposed MIMO antenna is integrated with multiple stubs on substrate having a size of 0.94λg × 0.94λg. The proposed design resonates at multiple frequencies of 1.8, 2.4, 5.2, and 5.8 GHz, respectively for GSM, ISM bands and WLAN wireless services which covers the bandwidth of 2.8%, 5%, 5%, and 5.6%, respectively with S11 ≤ −10 dB. Besides, the measured results provide a peak gain of 4.3, 3.1, 4.5, and 4.2 dBi at 1.8, 2.4, 5.2, and 5.8 GHz, omni directional radiation pattern with more than 80% of efficiency in all operating bands. The MIMO structure provides a good isolation of greater than 20 dB without decoupling structure, envelope correlation coefficient of ≤0.1, diversity gain of ≥9.99 dB, mean effective gain of &lt;1 dB, total active reflection coefficient ≤−10 dB, channel capacity loss of ≤0.25 bits/s/Hz. Finally, the housing effect of MIMO antenna is analyzed in the vehicular environment which provides good performance for Vehicular to Intravehicular communication.

Multiband antenna design with enhanced radiations using characteristic mode analysis

In this research, a multiband patch antenna design based on the superposition of multiple modes at the same resonant frequency is presented. The concept of the contribution of lower order modes (LOMs) with the higher order dominant modes (HODMs) is investigated using characteristic mode analysis (CMA). In order to provide similar broadside radiations in three bands, the radiating capability of the LOMs is enhanced in the resonant frequencies of HODMs. These HODMs when excited alone provide null in the broadside radiations of the antenna. Using a single feed, enhancement in the broadside radiations of the antenna is achieved with the superposition of multiple modes at the same resonant frequency. Based on the proposed concept two antennas have been designed and fabricated. The antenna provides stable and enhanced radiations. simulated and measured results are in good agreement. These antennas find application in many applications including communication systems, base station antennas, 5G communications, satellite communication etc.

Design and Analysis of Frequency Reconfigurable Antenna Loaded Complimentary Split Ring Resonator for Wireless Applications

This paper presents a multi-band reconfigurable antenna, circular patch antenna loaded with combination of rectangular and infinity shape complementary split ring resonator (CSRR). Four slots used for connecting the rectangular with infinity CSRR, where the four PIN diodes loaded in order to achieve reconfigurability. The circular patch has printed in Roger RT/5880 substrate having a dielectric constant of 2.2 within a size 37.35x34.35x1.57. Extraction of permittivity negative of the CSRR is discussed in detail. The proposed antenna can be used in modern and mobile communication devices.

Adaptive Beamforming with Sidelobe Level Control for Multiband Sparse Linear Array

Multiband antenna arrays have the capability of effectively working in multiple frequency bands and thus significantly simplify the antenna system. To further reduce the system overhead, this paper discusses the joint design of antenna selection and adaptive beamforming for multiband antenna arrays, where the sidelobe level is also controlled so as to alleviate the effect of unknown sporadic interference. Based on the maximum signal-to-interference-plus-noise ratio (SINR) criterion and sidelobe level constraints, the proposed multiband sparse array design is formulated into a nonconvex constrained nonlinear optimization problem with an l0,2-mixed norm regularization. This problem ensures that the same antenna positions are selected at all operating frequencies while the beamformer weights of each frequency are optimized independently. By exploiting the semi-definite relaxation and the reweighted l1,∞-norm approximation, the problem is converted into a series of convex subproblems and is then effectively solved by the proposed iterative reweighted method. Numerical results show that the proposed multiband sparse array significantly reduces the sidelobe levels in all operating frequencies while maintaining the maximum SINR, so it provides superior performance of interference suppression.

Design and development of multiband PIFA antenna for vehicular LTE/5G and V2X communication

This paper aims to introduce a custom-designed multiband planar inverted-F antenna (PIFA) suitable for automotive applications in LTE/5G schemes operating under 6 GHz, as well as Vehicle-to-Everything (V2X) communications. The PIFA antenna has a broad bandwidth capability, resonating from 950 MHz to 6 GHz. The proposed PIFA antenna is divided into three parts: the top, front, and back, resulting in a unique and effective antenna structure. The antenna is fabricated using a substrate made of FR4 material with a dielectric constant of 4.4. The whole measurements of the antenna are 54 × 38 × 25 mm3.The proposed PIFA antenna has been tested and has achieved a voltage standing wave ratio (VSWR) of less than 2 across the entire frequency range of 950 MHz to 6 GHz. Additionally, the maximum gain achieved by the antenna is 7.08 dBi at a frequency of 5.5 GHz, 6.81 dBi at 5.2 GHz, and 6.65 dBi at 5.9 GHz. The antenna also achieved a gain of 6.67 dBi at 3.8 GHz and a gain of 3.31 dBi at 1.7 GHz. Overall, this paper presents a well-designed and effective multiband PIFA antenna that is appropriate for use in vehicular applications. The antenna ability to cover a wide range of bandwidth and achieve high gain makes it an excellent candidate for use in LTE/5G systems and V2X communications.

Realization of circular polarized multiple band multi-mode OAM antenna using a ring patch for IoT applications

A multiband and multi-mode antenna with circular polarized conical patterns is suitable for achieving desired spectral efficiency, increased capacity, and spatial diversity for IoT applications. However, simultaneous excitation of such circular polarized multiple Orbital Angular Momentum (OAM) modes through a single patch antenna is challenging due to the complexity of simultaneously fulfilling distinct requirements of each mode. In this paper, a ring patch antenna is designed to excite different OAM states at different frequencies simultaneously. First, characteristic mode analysis is used to analyze the possibility of simultaneous excitation of multiple OAM modes at corresponding frequencies through a simple ring patch antenna. Then, a dual port ring patch antenna is designed and fabricated to verify the capability of generating multiple OAM states at corresponding frequencies. Furthermore, it also presents the guidance to suppress unwanted OAM modes.

New method based on genetic algorithm and Minkowski fractal for multiband antenna designs

Abstract In this paper, a new method based on a genetic algorithm and Minkowski Island fractal is proposed for multiband antennas. Three-antenna configurations are chosen to validate the proposed optimization procedure. The first configuration is a wide-band antenna, operating in the WLAN (wireless local area network) UNII-2C band. The second configuration is a dual-band antenna, operating in the WLAN UNII-2 and UNII-2C bands. In contrast, the third is a tri-band antenna operating in the UNII-2, UNII-2C, and UNII-3 bands. The optimization process is accelerated by using the Computer Simulation Technology (CST) Application Programming Interface which allows all genetic operators to be performed in MATLAB while the numerical calculations are running in the internal CST Finite-Difference Time-Domain -solver using parallel computing with GPU acceleration. All three designed configurations are manufactured using a $\textstyle0.8\;\text{mm}$ thick FR4 epoxy substrate with a relative dielectric constant of $4.8$ . The return loss and the radiation pattern’s measurements agree well with the simulation results. Further, the methodology presented can be very effective in terms of size reduction; the designed antennas are $24 \times 24 \times 0.8\;{\textrm{m}}{{\textrm{m}}^3}$ ( $460\;{\textrm{m}}{{\textrm{m}}^3}$ ).

A new printed multiband fractal triangular antenna for wireless application

A new printed multiband fractal triangular antenna for wireless application

A compact multiband antenna based on metamaterial for L-band, WiMax, C-band, X-band, and Ku-band applications

A compact multiband antenna based on metamaterial for L-band, WiMax, C-band, X-band, and Ku-band applications

Novel Multi-Band Substrate-Integrated Waveguide Antenna and Extension to a Deca-Band Antenna

In this letter, a deca-band substrate-integrated waveguide (SIW) antenna with filtering function is proposed. The number of slots was increased from 4 to 10, and the quad-band antenna design is extended to a deca-band antenna. At this time, good impedance matching characteristics are maintained without changing other parameters except the patch length. The fabricated deca-band antenna has 10 resonances between 3–4.4 GHz and a broadside radiation pattern characteristic at each resonance frequency, and the measured gain is 1.8–4.2 dBi.