Dual-Band Dual-Polarized Wearable Button Array With Miniaturized Radiator

Abstract

A dual-band dual-polarized wearable array is proposed, based on a miniaturized innovating button radiator topology. The diameter of the rigid button is only 19.5 mm (0.29 λ at 4.5 GHz), which optimizes the users' comfort, and makes it the smallest up to date in literature. The operational bands are 4.50-4.61 GHz and 5.04-5.50 GHz. The antenna thus covers the 4.5-4.6 unlicensed future 5th generation (5G) communication band for the internet of things (IoT), and the 5.1-5.5 GHz wireless local area network (WLAN) band, respectively. Two orthogonal linear polarizations are obtained in each band. A low mutual coupling between the button antenna elements (below -18 dB) and between the two ports within each element (below -20 dB) is achieved, guaranteeing a good diversity performance. The envelope correlation coefficient (ECC) and the specific absorption rate (SAR) performance are also analyzed. In order to demonstrate the robustness of the button antenna and to mimic realistic situations, a more complicated asymmetrical ground plane model of the button antenna is studied for the first time. A prototype of a two-element button array has been fabricated. The measurement results match well with the simulations. A 10-element button array is studied within the context of a 3-D channel model, taking into account the button element's radiation pattern. A high achievable spectral efficiency (SE) is obtained.

Recent Advances of Wearable Antennas in Materials, Fabrication Methods, Designs, and Their Applications: State-of-the-Art

“…Currently, a new miniaturized array button antenna was designed, as shown in Figure 9 d. It covered 4.5–4.6 GHz for the IoT applications, whereas the 5.1–5.5 GHz for the WLAN applications. Moreover, the design showed the lowest SAR in all these bands along with the S-parameters and total efficiencies were almost similar to the free space communication [ 280 ]. Thus, it shows the robustness of the proposed button antenna, as shown in Figure 9 d.…”

“… ( a ) Wideband button [ 275 ], ( b ) circularly-polarized button [ 276 ], ( c ) F-inverted button [ 279 ], and ( d ) array button antenna [ 280 ]. …”

Design and Evaluation of a Flexible Dual-Band Meander Line Monopole Antenna for On- and Off-Body Healthcare Applications

“…In particular, we have shown that the results are not sensitive to the presence of the human body, and insignificant detuning is observed at both bands when a 10 mm distance was maintained. Moreover, these evaluations are influential in determining proper antenna operation on the human body, and also pave the way for unique designs as mentioned by Guy A. E. Vandenbosch et al in [ 11 , 12 ], and Andrea Ruaro et al in [ 13 ] for future high-performance on-body applications. This paper is arranged as follows: after the introduction, Section 2 describes the design steps and the different parameters of the wearable monopole-shaped meander line antenna.…”

Compact monopole antenna for wireless body area network, wireless local area network, and ultrawideband applications

“…Many efforts have been made to minimize the size of the UWB antennas and the current challenge is to seek a balance between the bandwidth and the physical dimension of the antennas 1‐20 . Reference 1 presented a compact UWB planar antenna by using a corrugated radiator.…”

“…Many researches have been conducted in the past focusing on the compact monopole antenna for UWB applications and WBAN systems. A very low‐profile top‐loaded UWB antenna is proposed in Reference 20 but its relatively large size is not suitable for wearable applications. However, to the best knowledge of the authors, it is still a challenge to design a compact low‐profile omnidirectional wearable antenna based on a single radiator to cover both wireless local area network (WLAN) and UWB bands.…”