Wood-based composite materials for ultralight lens antennas in 6G systems

Abstract

Extremely high frequencies used in future wireless communication systems such as 6G require low loss materials to avoid wasting power and maintain acceptable efficiency . Furthermore, especially in the internet...

Implementation of a second‐order frequency selective surface filter at mmWave using paper and silver ink

“…In addition, effect from moisture protecting agent Glaco (SiO 2 based) [35] was investigated as it has been previously used to seal a nanocellulose based composites against the moisture [12]. A thin layer of it was sprayed on the filter and allowed to dry at room temperature, no change was observed in the measurement results.…”

“…The presented technique is feasible for mass production (roll‐to‐roll laser etching) where many different patterns are needed to manufacture because the pattering is performed with laser etching, not with the screen, which would require a new screen (stencil or stamp) per different pattern. Furthermore, this method is being investigated with the aim of using it with paper‐based RF lenses [12], where the pattern could be imprinted directly on the lens surface, improving the level of integration (a combination of an RF lens and a separate metasurface filter has previously been presented [28]). Thus, the paper‐based technology has been proven to be used in the larger scale of electronics applications in the future.…”

“…One of the innovations to come in 2030 is the sixth generation (6G) radio band [5]. The 6G band is a terahertz band (0.1-1.0 THz) which will bring many new possibilities for future communication, imaging and sensing application [6][7][8][9][10] and a wide variety of devices for various applications, such as absorbers [11], antennas [12,13], filters [14], lenses [15], etc. To meet the increasing demand for compact and high-integration systems, these devices must be miniaturized, structurally simple and economical.…”

An Ultralow-Loss and Lightweight Cellulose-Coated Silica Foam for Planar Fresnel Zone Plate Lens Applications in Future 6G Devices

“…In the next step, the carbon skeleton was removed by annealing in air at 800 °C, leaving behind the porous, extreme low-permittivity silica foam (real part of dielectric permittivity, ε r (Re) = 1.01 ± 0.003 at 300 GHz and porosity: 98.9% ± 0.1%). As the pore size of the silica slabs was not small enough for a subsequent direct deposition of metal patterns with the required definition, a thin cover layer of nanocellulose (with ε r (Re) = 3.59 ± 0.01 [36]) was applied on the envelope surface of the foams by immersing them into a cellulose nanofiber suspension (0.1 wt.%, dip for 1 s). The coating improved the surface roughness (root mean square height) significantly from 48.1 to 16.4 μm according to analyses carried out using an optical profilometer (Bruker Contour GT-K) [Fig.…”

Advances in Antenna-Based Techniques for Detection and Monitoring of Critical Chronic Diseases: A Comprehensive Review

“…They have a wide range of applications that include Advanced Mobile communication (4G, 5G, 6G technologies), Wireless Local Area Networks (WLAN), IoT (Internet of Things), Bluetooth, Radio Frequency Identification (RFID), Power management and Health Monitoring system. [1]- [3]. Recent advancements in the antenna designing field have increased the demand for wireless health monitoring systems as during Covid-19 patients and doctors are most vulnerable to the coronavirus which makes them hesitant to make any physical contact for a timely treatment, which may cause severity in the disease of the patients and eventually death may occur.…”