Textile Antenna Research Articles

Design and development of jeans textile antenna for wireless broadband applications

This paper proposes a design of a compact jeans textile wearable antenna with miniaturized structure. This textile antenna is designed for wireless broadband applications. This antenna is resonating at 3.4 GHz. This antenna is designed using FR-4, Jeans and Denim as a substrate. The shaft shape is mounted on three different substrates (FR4, denim, and jeans), and the antenna is designed, simulated, and the parameters are analyzed. In the proposed design, textile material (Jeans, Denim) is used as a substrate and copper is used to make ground & patch. The textile material is used because it is wearable, washable, very economical, and flexible. The simulated antenna parameters like bandwidth, return loss, radiation pattern, gain and efficiency are presented. The overall size of the antenna is 30 × 30 mm2. Due to its small size, the proposed antenna may have practical applications in the smart wearable textile fields.

Fabrication and Characterization of a Leaky-Lens Photoconductive Antenna on Low-Temperature Grown GaAs Membranes

State of the art THz pulsed commercial systems operating over large bandwidth suffer from high dispersion or low radiation efficiency due to the poor coupling between the transmitter and receiver photoconductive antennas (PCAs). In this work, we present the fabrication and characterization of a leaky lens photoconductive antenna (PCA) that has the potential to solve this problem. The presented PCA is based on a low temperature grown gallium arsenide (LT-GaAs) membrane with a 1:15 bandwidth coverage (0.1 THz – 1.5 THz), where the frequency response if constant. In order to fabricate the PCA on a LT-GaAs membrane, a novel fabrication process is developed. This process is dramatically faster than previously used processes (∼1.5 hours instead of ∼20 hours). Furthermore, an experimental validation of the radiated power together with the comparison to a standard bow-tie based PCA fabricated on the same LT-GaAs wafer is shown in this paper. We show that the PCA source on the LT-GaAs membrane is more efficient due to the enhanced leaky wave radiation. The leaky lens PCA stands out as a great candidate to improve the coupling efficiency in THz pulsed commercial systems, where the maximum laser power that can be used is limited by the dispersion in the optic fiber.

Compact Coplanar Waveguide Antenna Using Arm Patch for Software Defined Radio

This article proposes a compact coplanar waveguide (CPW) antenna with a semicircular patch and patch arm above the feed line. The method used in this antenna research is experimental, with antenna parameter optimization, fabrication, and measurement steps. The antenna was 40 mm × 46 mm × 0.8 mm and was printed on an FR4 substrate. Antenna optimization was carried out with CST Studio Suite to obtain optimal results. Based on return loss measurement results, the proposed antenna has an operational frequency of 2 GHz–7 GHz. The antenna arm has a significant effect on the operational frequency of the antenna, as proven by a parameter study of the antenna arm. Parametric studies were carried out on the antenna by investigating the influence of geometric parameters on the frequency characteristics. Optimization results were printed then measured by a Vector Network Analyzer (VNA) and a spectrum analyzer. The fabricated CPW antenna has a wider operating frequency than the simulation. An omnidirectional radiation pattern was observed at 2 GHz–4 GHz. The antenna has been used as a transmitter and receiver at 2.4 GHz, 3 GHz, and 4 GHz. The antenna is able to receive the signal emitted from the signal generator.

Design and Realization of Wearable Textile Slotted Waveguide Antennas.

The design of wearable antennas presents a challenge from multiple perspectives, as they must meet technical requirements and satisfy safety standards while also being suitable for integration into clothing and aesthetically pleasing. In recent years, the development of conductive fabrics has, in many ways, allowed for significant progress in the manufacturing of wearable antennas, and in previous work, we developed textile slotted waveguide antennas using conductive textiles and traditional sewing processes. However, various aspects of the design and realization of such antennas remain challenging. In particular, this work investigates the issue of using foam-based molds, which enables the realization of thin, flexible, wearable antennas, as well as the issue of antenna feed, specifically the transition from a classic coaxial transmission line to a waveguide. The design of the transition was focused on simplicity and robustness, due to which we limited the number of degrees of freedom in the design process in order to achieve a structure suitable for mounting on textile waveguide antennas. In addition, the antenna design procedure and the body-channel model were considered in order to optimize the performance of the antennas and the wireless body-centric system itself. Several prototypes of different kinds were developed in the 5.8 GHz ISM band, confirming the feasibility of the proposed concepts through experimental results.

A Novel Miniaturized Triangular Slotted and DGS Based Inverted Circular Key Shaped Textile Antenna with Enhanced Bandwidth for C, WLAN, RAS, N795G Band Application

A Novel Miniaturized Triangular Slotted and DGS Based Inverted Circular Key Shaped Textile Antenna with Enhanced Bandwidth for C, WLAN, RAS, N795G Band Application

Frequency Selective Surface Textile Antenna for Wearable Applications

Frequency Selective Surface Textile Antenna for Wearable Applications

An Optimized Wearable Textile Antenna Using Surrogate Ensemble Learning for ISM On-Body Communications

An Optimized Wearable Textile Antenna Using Surrogate Ensemble Learning for ISM On-Body Communications

Pattern-Reconfigurable Flexible Textile Antenna Using RF-Switch Integrated Circuits

A pattern-reconfigurable flexible textile antenna covering the 2.45 GHz Industrial, Scientific and Medical (ISM) band is presented. The design utilizes RF-switch Integrated Circuits (ICs) packaged into reconfiguration modules as switchable vias to change between the omnidirectional and broadside radiation modes of a center-shorted patch. Analytical models to calculate the resonance frequency of each mode are developed to give more physical insights into the mode resonance and assist the design optimization. An antenna prototype is experimentally characterized to further validate the concept and analysis of the proposed antenna structure. The stable performance under on-body environment and various bending test conditions demonstrates the antenna operation in wearable scenarios.

Textile Characterization for Wearable Antenna Application Using Transmission Line Method

This proposed work introduces the textile characterisation analysis based on the effects of fabric thickness and dielectric properties using the transmission line method for a wearable textile antenna. The return loss (S11) and transmission loss (S21) were analysed for denim, felt and Tencel in correlation with the conductivity properties using Computer Simulation Technology with Rogers 5880as the reference sample. By varying the fabric thickness from 0.5 mm to 4 mm, the optimum thickness and type of fabric can be identified from the S11and S21parameters. In the transmission line simulation, the sample-under-test is a stripline with the conductivity values from 10-2to 108S/m. Results are further plotted against the thicknesses to observe the behaviour of all three textiles samples. The results show that Felt substrate with 3 mm thickness give the best performance. The felt substrate demonstrates the best transmission performance judging from the lowest transmission loss due to the low tangent loss followed by Tencel and denim.For accuracy analysis, the actual and calculated conductivity were also presented to show the textiles performanceat low and high region of conductivity. The study reveals the importance of choosing the correct substrate with suitable dielectric and electrical properties before being implemented into the antenna design for good efficiency.

6G Broadband and High Directive Microstrip Antenna with SIW and FSSs

Sixth-Generation (6G) wireless communication networks require the fabrication of broadband and high directivity microstrip antennas to offset the high atmospheric path loss beyond 100 Gigahertz (GHz). In this paper, we designed and proposed a couple of high-gain and broadband microstrip array antennas that have been designed within a Finite Integration Technique (FIT) solver at Computer Simulation Technology Microwave Studio (CST MWS) software in a series-parallel feeding method for a resonance frequency above 107 GHz. A Substrate-Integrated Waveguide (SIW) with dual outputs has been used at these antennas and with WR-08 waveguide that covers the 90-140 GHz frequency range, while the first was without Frequency Selective Surfaces (FSSs), and the second was with the FSSs to increase the antenna directivity further. The first design was simulated with a Finite Element Method (FEM) solver at Ansys High-Frequency Structure Simulator (HFSS) to compare the simulation results of this antenna. This comparison's peak gain and Bandwidth (BW) were correspondingly 25.3 dB, 12.5 GHz, 23.1 dB, and 11 GHz from the Ansys HFSS and the CST MWS. Thus, the accuracy and the slight deviation of the compared simulation results from each other validated the offered 6G antenna designs. Therefore, after experimental verification, the proposed antennas can be employed in 6G future wireless communication networks.

Multi‐Material Aerosol Jet Printing of Al/Cuo Nanothermites for Versatile Fabrication of Energetic Antennas

AbstractIn the present study, a nanoscale Al/CuO thermite system is patterned using a multi‐material aerosol jet printing technology. Morphological analysis of samples manufactured with different printing configurations reveal a strong effect of the printhead design on microstructure and degree of mixing between the constituent materials, providing insight on fundamental mechanisms of inline aerosol‐phase mixing during printing. The high‐resolution patterning capability of aerosol jet printing is leveraged to fabricate both blended nanoscale Al/CuO thermites and antennas containing the nanothermite, which exhibit rapid and low‐energy ignition upon exposure to a 2.45 GHz free space electromagnetic field, characterized by an ignition delay of ≈130 ms and ignition energy of ≈216 J. Moreover, the versatility of this approach is demonstrated by manufacturing compositionally graded samples, establishing multi‐material aerosol jet printing as a compelling and versatile platform for microscale energetic device fabrication with broader utility for graded materials. This work shows promise for use of the technique for in situ manufacturing of standalone and integrated energetics and electromagnetic devices.

Design and analysis of multiple beams phased array microstrip antenna for 5G applications

The paper presents a novel and compact antenna array design fed through a 3 dB BLC for producing phase shift in the array. Beam steering is an attractive design feature for avoiding obstacles in the path of the beam. It is achieved by switching the beam to another path by simply varying the phase shift between elements. The proposed structure exhibits resonance in the frequency having range of 27.6 GHz −29.6 GHz with a minimal return loss value of −45 dB for frequency applications of 28 GHz, which can be further employed for 5G frequency applications, there are two multiple beams observed, with main beam at theta equal to −35 degrees, the main beam shifts to +28 degrees by changing the feed port of the coupler. A stable gain of around 11.5 dB is obtained for the entire frequency range. The input phase has been varied for different elements in the array, and best results were obtained for a 90 degree phase difference, which required the use of a 3 dB BLC. Rogers RT Duroid 5880, having a dielectric of 2.2 and a 0.51 mm dielectric height, was used as a substrate for antenna fabrication. The simulations were performed on the CST Microwave studio and the measurements were done on VNA (Agilent N5247A).

5G millimeter wave wideband MIMO antenna arrays with high isolation

In this paper, a compact two-port MIMO antenna array system is described. The antenna array spans the range from 27 to 40 GHz, whereas the impedance of the antenna element is matched at 50 Ω. The gain of the antenna element is between 5.5 and 8.5 dBi, and its radiation efficiency is between 65 and 90%. With high impedance matching for 5G MMW (Millimeter Wave), particularly at 28 GHz and 38 GHz, the 2-port antenna array operates in the frequency range of 27–40 GHz. The suggested MIMO array operates effectively with a gain of approximately 10 dBi and a radiation efficiency of approximately 95%. The antenna array's overall dimensions are a length of 55.27 mm, a width of 27.635 mm, and a depth of 1.6 mm with partial ground. A FR-4 substrate is used in the antenna's fabrication, greatly reducing the cost. In the antenna array, a decoupling surface is used between the antennas, with orthogonality being maintained between the ports to reduce mutual coupling. The results of the modelling show a reduction in the measured mutual coupling between array ports of less than − 35 dB. An envelope correlation coefficient (ECC) of less than 1 × 10–4 is preferable. Additionally, the channel loss capacity is less than 0.3 bits/s/Hz, the mean effective gain is approximately − 6 dB, and the total active reflection coefficient is upgraded to be less than − 30 dB. Moreover, a diversity gain of approximately 10 dB is achieved. The proposed construction was created using CST Microwave Studio 2019. When the antennas are constructed and tested, the experimental outcomes surpass those of the simulation. Each antenna element is 27.635 mm long, 27.635 mm wide, and 1.6 mm thick. Slots in the radiating circular patch antenna element could be used to improve the radiation characteristics across the intended bands. The parametric study specifies that the distance between the antenna elements should be 0.5 λ, where λ is the operational wavelength.

Fabrication of conformal antenna by 3D printing of recycled thermoplastic polyurethane on fabric

In this study, a recycled thermoplastic polyurethane (TPU) substrate was 3D printed on cotton-lycra fabric (CLF) using the fused filament fabrication (FFF) method to create a microstrip patch antenna (MPA) following the sustainable development goal (SDG) (with a special focus on the industry, innovation, and infrastructure). Some recent studies have highlighted that the FFF process may be employed for required alterations in infill structure, and density, to provide accurate dimensional features for MPA (for wearable applications). It has been reported that for wearable applications, the conformal design of MPA is one of the major requirements. But hitherto little has been reported on the process capability of FFF for the conformability of MPA. This study highlights the process capability of FFF by considering the strain and strain hardening coefficient (SHC) of the MPA substrate, leading to a conformal antenna, which may be further used in wearable applications (at different bending positions without disturbing the antenna performance). Further, the MPA was designed and simulated at a resonating frequency (Rf) of 4.9 GHz using high-frequency structural simulation (HFSS) software, which shows the bending of MPA at a radius of 30 mm, 40 mm, 50 mm, and 60 mm resulted in Rf of 4.81 GHz, 4.81 GHz, 4.81 GHz, and 4.82 GHz respectively which lies in the range and shows the conformability of the designed MPA at different bending positions.

Bio-based substrate for flexible electronics - application to a 2.45 GHz wearable patch antenna

In this paper, a bio-based and biocompatible polymer, Cellulose Laurate (CL), is proposed for flexible radio-frequency (RF) electronics. The synthesis of CL films together with their characterizations (chemical, thermal, mechanical and dielectric) are presented. The results obtained allow considering this material for RF flexible applications as a possible alternative to petrosourced substrates. Therefore, CL has been used to fabricate a flexible patch antenna that operates in an industrial, scientific and medical (ISM) frequency band. The central frequency selected is 2.45 GHz. The antenna fabrication process is based on the combination of laser structuring and the use of copper adhesive tape. Measurements of the antenna reflection coefficient and radiation patterns show that CL is a good candidate as a RF substrate. Furthermore, it is demonstrated that the antenna performance is only slightly impacted under bending conditions.

Design and fabrication of a super-wideband transparent antenna implanted on a solar cell substrate

In this study, an antenna with transparent super wideband CPW technology has been designed and built with the combination of solar panels for use in wireless communication equipment and systems that require mobile power. The transparency value of the antenna is 63.3%, which is an acceptable value for the optimal use of sunlight. The proposed antenna was designed and measured on a plexi-glass substrate with a dielectric constant of {{varvec{upvarepsilon}}}_{{varvec{r}}}=4.4 and various thicknesses, the proposed antenna was designed and measured. The copper sheet has a high electrical conductivity and therefore it was selected for the antenna's radiating component as compared to earlier techniques that employed metal oxide. All simulations were done with CST microwave studio software and frequency domain solver. The results indicated that the antenna's operating frequency ranges from 2 to 32 GHz. The results of the computations indicated that the antenna's peak gain and peak efficiency are 8.1 dB and 90%, respectively. Various multiple-input and multiple-output (MIMO) performance parameters, including the envelope correlation coefficient (ECC), diversity gain (DG), average effective gain (MEG), total active reflection coefficient (TARC), and channel capacity loss (CCL), were analyzed to demonstrate the antenna's performance.

Notch-band eliminator wideband CSRR loaded monopole fractal antenna for ISM and PCS communications

PurposeThis paper aims to present a low-cost, edge-fed, windmill-shaped, notch-band eliminator, circular monopole antenna which is practically loaded with a complementary split ring resonator (CSRR) in the middle of the radiating conductor and also uses a partial ground to obtain wide-band performance.Design/methodology/approachTo compensate for the reduced value of gain and reflection coefficient because of the full (complete) ground plane at the bottom of the substrate, the antenna is further loaded with a partial ground and a CSRR. The reduction in the length of ground near the feed line improves the impedance bandwidth, and introduced CSRR results in improved gain with an additional resonance spike. This results in a peak gain 3.895dBi at the designed frequency 2.45 GHz. The extending of three arms in the circular patch not only led to an increase of peak gain by 4.044dBi but also eliminated the notch band and improved the fractional bandwidth 1.65–2.92 GHz.FindingsThe work reports a –10dB bandwidth from 1.63 GHz to 2.91 GHz, which covers traditional coverage applications and new specific uses applications such as narrow LTE bands for future internet of things (NB-IoT) machine-to-machine communications 1.8/1.9/2.1/2.3/2.5/2.6 GHz, industry, automation and business-critical cases (2.1/2.3/2.6 GHz), industrial, society and medical applications such as Wi-MAX (3.5 GHz), Wi-Fi3 (2.45 GHz), GSM (1.9 GHz), public safety band, Bluetooth (2.40–2.485 GHz), Zigbee (2.40–2.48Ghz), industrial scientific medical (ISM) band (2.4–2.5 GHz), WCDMA (1.9, 2.1 GHz), 3 G (2.1 GHz), 4 G LTE (2.1–2.5 GHz) and other personal communication services applications. The estimated RLC electrical equivalent circuit is also presented at the end.Practical implicationsBecause of full coverage of Bluetooth, Zigbee, WiFi3 and ISM band, the proposed fabricated antenna is suitable for low power, low data rate and wireless/wired short-range IoT-enabled medical applications.Originality/valueThe antenna is fabricated on a piece (66.4 mm × 66.4 mm × 1.6 mm) of low-cost low profile FR-4 epoxy substrate (0.54 λg × 0.54 λg) with a dielectric constant of 4.4, a loss tangent of 0.02 and a thickness of 1.6 mm. The antenna reflection coefficient, impedance and VSWR are tested on the Keysight technology (N9917A) vector network analyzer, and the radiation pattern is measured in an anechoic chamber.

Mutual coupling reduction in a textile ultra-wide band MIMO antenna

This paper presents a mutual coupling reduction technique in a textile ultra-wideband (UWB) multiple-input–multiple-output (MIMO) antenna system implemented on a textile substrate. The compact textile UWB MIMO antenna consists of two patch antennas implemented on a felt textile substrate. The compact size and close placement of the antennas in a MIMO system cause higher mutual coupling which deteriorates the performance of the communication systems. To minimize the mutual coupling, Parasitic Elements and Defected Ground Structures are used in the designed textile UWB MIMO antenna. The MIMO antenna performed very well over almost the whole UWB frequencies ranging from 3.29 GHz to 13.3 GHz. The simulated and the measured parameters showed a good impedance matching with an impedance bandwidth of 133.4%. The results showed an improvement of 20 dB isolation at certain frequencies without impacting the reflection coefficient S11 and the antenna impedance bandwidth. The MIMO antenna has good diversity performance parameters in terms of Envelope Correlation Coefficient (ECC), Diversity Gain, Mean Effective Gain (MEG) and radiation pattern and the results indicate that the textile antenna is suitable for UWB MIMO applications. The overall size of the antenna is 30x60 mm2. Fully embroidered structure provides freedom of movement and comfort, so it is a good fit for Wireless Body Area Network applications.

Advanced ANN model for DoA estimation in smart textile wearable antenna array subsystem

AbstractArtificial neural networks‐based module for fast direction‐of‐arrival (DoA) estimation of the signal received by multi‐element textile wearable antenna array (TWAA) is proposed in this paper. The developed multilayer perceptron (MLP) DoA module considers the effects of changing the gain of the antenna elements, the distance between the antenna elements and their resonant frequencies during the movement of the TWAA wearer and the crumpling of the textile. The inputs of the MLP DoA module are the elements of the spatial correlation matrix of the signal sampled by the TWAA and the output is the angular position of the signal source in the azimuthal plane. The influence of the number of TWAA elements on the accuracy of the MLP DoA module in DoA estimation under textile crumple conditions is investigated. The performances of the MLP DoA module under increased noise conditions are investigated, as well as its behavior under different degrees of textile crumpling. A comparison was made between the proposed module and the corresponding root MUSIC DoA module in terms of accuracy and speed of DoA estimation.

Structural design and model fabrication of cable-rib tensioned deployable parabolic cylindrical antenna

Deployable mechanisms with light weight and high storage ratio have received considerable attention for space applications. To meet the requirements of space missions, a parabolic cylindrical deployable antenna based on cable-rib tension structures is proposed and verified by a physical prototype. The parabolic cylindrical antenna adopts simple parallel four-bar mechanisms to construct the basic deployable unit, and the cylindrical direction dimension can be easily extended by modularization, which has obvious advantages in storage ratio and area density. Considering the complexity of the entire antenna structure design, including cable networks and flexible trusses, the form-finding design optimization model of a parabolic cylindrical antenna is established using the force density sensitivity method, and then the kinematics analysis of the deployable mechanism is carried out. Finally, a single-module prototype with a deployable diameter of 4 m × 2 m was designed and fabricated. The results of the ground deployment process test and surface accuracy measurements show that the antenna has good feasibility and practicability.