Figure - available from: International Journal of Antennas and Propagation
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Fabricated antennas with copper sheet and transparent conductive films. (a) CUWB. (b) TRUWB. (c) TUWB.
Source publication
Ultra-wide band (UWB) antennas with transparent indium zinc tin oxide (IZTO)/Ag/IZTO multilayer electrode films are presented. The geometry of the radiator of the proposed UWB antenna is a simple semicircular shape, and acryl is used for the transparent substrate. Three types of proposed antennas are used for the comparison: first, an UWB antenna w...
Similar publications
Air-stable thin films (50–720 nm thickness) composed of a carbon-centered neutral π-radical with high and anisotropic electrical conductivities were fabricated by vapor deposition of 4,8,12-trioxotriangulene (TOT). The thin films were air-stable over 15 months and were the aggregate of TOT microcrystals, in which a one-dimensional π-stacking column...
Citations
... However, the performance of such MLF oxides is considered relatively poor as compared to non-transparent antennas. The transparent antennas having MLF ground planes showed poor efficiency in comparison with other types of transparent antennas [11], [12]. The MLF conductivity is considerable, however, increased sheet resistance due to extremely thin film causes poor efficiency. ...
An optically transparent MIMO antenna with close proximity two-element square patch antenna elements has been presented here to achieve forthcoming requirements of compactness, optical transparency and visual aesthetic for 5G wireless communication and Internet of Things (IoT) applications. A simple, thin optically transparent and more innovative decoupling structure with easier to design closely spaced transparent MIMO antenna configuration is proposed, optimized, and analyzed to achieve higher isolation and diversity gain performance even with close proximity of patch antenna elements. Polyethylene terephthalate (PET) material, which is thermoplastic polymer resin of the polyester family is used as a substrate to achieve optical transparency. The wired metal mesh parameters are taken into consideration to achieve required optical transparency as well as isolation and radiation performance for the MIMO antenna. The performance of the proposed MIMO antenna is also verified through fabricated prototype.
... Multilayer CTO technology (CTO/metal/CTO) reaches lower sheet resistances: for the multilayer ITO/Ag/ITO, it's around 7 Ω/square for a transparency around 95% [4]. IZTO/Ag/IZTO is even more interesting [5] due to its flexibility and low manufacturing cost. However, this technology does not allow to achieve sheet resistances lower than 1 Ω/square while preserving a high optical transparency. ...
... These materials have low sheet resistance and high transparency. However, the high optical haze resulting from scattering of the nanowires and mesh patterns is undesired in high-resolution displays [25]. Moreover, they are usually fabricated through precise patterning or complicated chemical synthesis processes which makes fabrication procedures expensive and complex [26,27]. ...
In this paper, a transparent antenna made with a new structure of ITO/Ag/ITO is proposed. Overcoming the physical limitations of transparency and conductivity is an important problem with transparent materials. By studying and comparing previously reported transprent materials, a transparent electrode with thin film Ag inserted between two layers of ITO instead of a single layer is selected for a highly efficient transparent antenna. This electrode has low sheet resistance (3.1 Ω/sq) relative to its high transparency (88 % at 550 nm), which is a factor that can increase the efficiency of the antenna. In general, it is difficult to measure sheet resistance (SR) using a 4-point DC probe for very thin films (thickness of transparent material is less than the skin-depth). Therefore, a form of reverse engineering that can estimate DC sheet resistance using RF SR was presented and verified. As a result, it was possible to predict and design the performance of the transparent antenna with the new material structure. The selected transparent material is applied to design the wideband transparent antenna and the design process for wideband performance is covered in the paper. The proposed antenna with ITO/Ag/ITO was implemented for verification. The peak efficiency of the fabricated antenna was 66 %, and the measured bandwidth was 123 % (from 2.5 GHz to 10.6 GHz), which is the best performance than previously reported transparent antennas.
... For instance, a UWB transparent antenna is designed for 5G application with dimensions of 10 × 12 mm 2 [26]. Some other UWB antennas were used different materials to design a low-profile antenna such as PDMS [27], AgHT-8 [28], AgHT-4 [29], indium zinc tin oxide (IZTO) [30], and ITO [31]. Fig. 1 and Table 1 show the simulated and fabricated prototype, measurement setup, and parameter dimensions of the proposed antenna. ...
A layer of Kapton polyimide with the dielectric constant of 3.5 as substrate and indium tin oxide (ITO) as conductor (10 × 10 × 0. 375 mm3) are used to construct a miniaturized flexible transparent ultrawideband (UWB) antenna. The antenna's performances are investigated and evaluated using an ITO transparent conductor in both frequency and time domain. The proposed antenna achieves the wide bandwidth (BW) of 3.26-23.37 GHz, more than 65 % radiation efficiency for most of the working BW, and maximum radiation efficiency of 90 percent at 15 GHz. Besides, it depicts a stable radiation pattern at most of the operating band and a maximum gain of 3.87 dBi. The good agreement between the simulation and measurement results, time-domain considerations, and the reconstructed image of the tumor makes the antenna capable of working in many applications, especially for breast and skin cancer detection.
... Another flexible UWB antenna designed using PDMS as a substrate [19]; besides, others used AgHT-8 [20] and AgHT-4 [21]. Apart from those, others designed narrow-band and wideband antennas for the 5G applications at the higher frequency bands like mm-wave communications and devices [22][23]. ...
When 4G showed several limitations on data rate transition and the required BW for communication increased day by day, a new alternative has been sought to compensate those drawbacks. Therefore, scientists suggested sub-6G (5G) and 6G to improve communications limitations. This paper presents an antipodal Vivaldi metamaterial-based flexible wearable ultrawideband (UWB) antenna for sub-6G, internet of things (IoT), and wireless body area network (WBAN) applications working at the range of 4.25-35 GHz. The miniaturized proposed antenna (15 × 10 mm 2) comprises a layer of denim with h= 0.7 mm and the resonator made of ShieldIt. A modified leaf-shaped antipodal patch is developed to have a broad bandwidth with high directive gain and high efficiency to be an acceptable candidate for sub-6G communications. First, the patches are cut by two half-circle arcs, two stubs at the front and two L-shape slots at the back to improve the radiation efficiency of the antenna while suppressing the undesired surface waves. Then, the antenna is loaded with the proposed metamaterial arrays to extend the bandwidth (BW) and enhance the gain and directivity of the antenna utilizing a semiflexible Rogers 5880 substrate (h= 0.508 mm). Besides, all the antenna's parts are optimized and formed to obtain maximum directive gain and radiation efficiency of 8.97 dBi and 98 %, respectively. The good agreement between simulation and measurement results proves the antenna capability in working for sub-6G, IoT, and WBAN applications.
... The measurement results showed that the proposed transparent antennas can be used as small RF passive components for low performance levels. However, the transparent antennas with MLF ground planes or large dimensions had very low efficiency compared with the reference antennas [7], [8]. In other words, the silver-coated polyester film (AgHT) was used as a radiator and a ground plane of transparent coplanar waveguide-fed antennas [10]. ...
... The radiator and ground plane were attached at the front and back of the substrate, respectively. Fig. 5 shows the dimensions of the antenna design proposed in the previously published papers [8]. The proposed design can be easily extended to multiple services by adding a recessed line. ...
... In a previous study about μMMF antennas, the structure of μMMF were analyzed using a scanning electron microscope (SEM) [8]. ...
This communication presents the design, fabrication and measurement of transparent antennas with metal mesh (MM) for wireless transparent applications such as smart windows, transparent mobile devices, transparent-internet of things (IoT), etc. The MM was proposed as a transparent electrode with high conductivity in electrical performance, with proper transparency in optical performance and low fabrication cost compared to a traditional transparent thin film electrode. To analyze the performance of a transparent antenna fabricated by MM, the antennas were designed to operate in the 2.4 ~2.5 GHz WLAN band (802.11b). The conductive metal of transparent MM patch antennas was designed using a square-lattice structure and was fabricated using wired metal mesh (WMM) with copper wire (0.2 mm -0.5 mm). In addition, micro metal mesh film (μMM) consisting of thin copper wire (20 μm) was used to fabricate transparent patch antennas. The realized gain, efficiency, front-to-back ratio and radiation patterns of the transparent MM patch antennas are discussed for various combinations of radiator and ground planes. Overall, the transparent MM patch antennas offer optical transparency, maintain sufficient performance and could possibly be used in wireless transparent applications.
We propose a novel transparent metasurface antenna (metantenna) based on indium tin oxide (ITO) material for simultaneously achieving wireless energy harvesting (WEH) at radio frequency (RF) bands and efficient transmission of visible light. We adopt the design method of aperture-coupled metantenna to realize broadband and low-profile RF WEH. Then, we replace the conventional opaque metal material with an ITO coating with a sheet impedance of
$1~\Omega $
/sq to achieve the transparency of the proposed design. In order to obtain the balance between electrical performance and optical transmittivity (OT), we modify the metasurface structure to further improve the OT of the metantenna. The fabricated transparent metantenna shows an OT of more than 50%. A measured impedance bandwidth of 43.6% from 1.40 to 2.18 GHz is obtained to cover 2G and 3G wireless communication bands. Through designing the broadband rectifying circuit and the energy management circuit, we can obtain the maximum RF-dc efficiency of 65% and a stable dc output voltage of 3.4V, while the overall RF energy harvesting efficiency could reach 14.5% with the power input of 0 dBm. In addition, through the solar energy harvesting test, we can demonstrate the potential of the proposed design to work with solar panels for realizing efficient RF/solar hybrid energy harvesting.
In this article, a feasibility study on an optically transparent planar dipole antenna using liquid salt water at wide ultra-high frequency (UHF) band (470–771 MHz) for application in external antenna of ultra-high-definition television (UHD TV) is presented. The most significant reason behind using liquid salt water for transparent antenna applications is its excellent average optical transparency (OT
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) (>95% at salinity of 40 ppt) compared with other typical solid transparent thin-film electrodes such as indium tin oxide (>73%) or multilayer films (>78%). Each conductive arm of the proposed dipole is constructed from a salt-water layer held between two clear planar acrylic layers (
$\varepsilon _{r} = 2.61$
, tan
$\delta = 0.01$
, OT
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> 90%) (acrylic/salt water/acrylic; ASA) due to surface tension. To investigate the electrical and optical properties of the ASA structure, we analyze the surface tension to determine the thickness of the salt-water layer that finalizes its sheet resistance and OT
<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">av</sub>
. The average gain and efficiency of the antenna are 1.72 dBi and 74%, respectively, in the operating UHF band. This makes the proposed antenna a good candidate for application as a transparent external antenna in UHD TVs and proves that it is possible to use salt water for high-frequency devices.
