Meta‐surface enabled hepta‐band compact antenna for wearable applications

Abstract

This study proposes a new hepta‐band antenna that consists of an inductive ground plane and slots loaded patch for the multiband body‐worn scenario. The phase distribution is optimised by considering a 7 × 7 array of periodic square patches on the metallic ground‐backed substrate in such a way that resonant modes of patch slots interact with the resonant modes of meta‐resonators of inductive ground to achieve hepta‐band behaviour with desired radiation characteristics. Each unit cell corresponds to a phase shift of 3.6° out of available phase distribution of 180°. The seven bands are targeted at 1.8, 2.45, 2.96, 3.5, 3.8, 4.2, and 4.5 GHz which supports GSM (1.8 GHz), WLAN (2.4 GHz), LTE (2.5 GHz), Wi‐MAX (3.5 GHz), sub‐6 GHz 5G band (3.4‐4.2 GHz), navigation (2.96 GHz), and satellite (4.5 GHz) applications. It is also demonstrated that an inductive ground plane can be used to get reduced SAR and increased FBR, making antenna useful for wearable applications. The proposed antenna has a patch size of 28.84 × 28.84 mm upon a 0.4 mm thick substrate of permittivity 4.3. Inductive ground is made of via‐free periodic square patches each of size 5 × 5 mm on the 2.6 mm thick metallic ground‐backed substrate.

State‐of‐art design aspects of wearable, mobile, and flexible antennas for modern communication wireless systems

“…Analysis is to be done for wearable antennas including SAR modeling, different bending measurements as well as on body measurements. In a previous study, 40–62 the authors discussed various types of on‐body wearable antenna designs. Paper, 40 describes a rectangular shaped patch antenna having a partial ground for 2.4 GHz applications.…”

“…This article distillates on microstrip antennas used in portable wireless systems 7 as shown in Figure 1. Antennas like MSAs, wearable structures and conformal geometries are well harmonized with requirements of handheld devices 7–118 . Study on planar antennas 7–39 is diverse and interesting due to which the discussion is essential.…”

“…The design of antenna in wearable fields is a big task because of the human body in vicinity of the functioning antenna 40–62 . Wearable antennas have a need for body phantom to analyze the results practically 46 .…”

An EBG-Based Triple-Band Wearable Antenna for WBAN Applications

“…References [8,9,12] proposed a variety of dual-band wearable antennas loaded with metamaterial structures. To further increase the number of bands, some triple-band and multi-band wearable antennas have also been reported [13][14][15][16][17][18]. Reference [13] presented a triple-band Micromachines 2022, 13,1938 2 of 12 antenna with a periodic square groove on the ground and a Hilbert-shaped array for the radiating layer, but the safety for the human body has not been evaluated.…”

“…In [17], a wearable multi-band CPW-fed slot dipole antenna was incorporated for WBAN applications, which covers the 2.4/5.2/5.8 GHz WLAN, 3.5 GHz WiMAX, and 4.4 GHz C-bands. Reference [18] designed a hepta-band antenna, consisting of a slotted radiator and a 7 × 7 array of periodic square patches. This antenna utilizes the inductive ground plane to reduce the SAR value.…”