Wireless body area networks (WBANs) have gotten a lot of interest as the need for wearable gadgets like smart watches, eyewear, and clothing grows. WBAN applications need the use of a conformal antenna. A low-profile IR-UWB antenna and an all-textile higher order mode circular patch antenna for omnidirectional radiation were used to meet this need. To achieve maximum power output, researchers need to maintain the antenna's efficiency as high as feasible while designing a lightweight antenna for wireless power transfer. The need for tiny textile antennas with high gain and broadband features has risen in response to the fast growth of wireless power transfer. Microstrip patch antennas provide a number of advantages, including a cheap cost, a low profile, a light weight, and a simple manufacturing method. Increases in substrate thickness, antenna efficiency, use of a low dielectric substrate, and different impedance matching and feeding techniques are all examples of ways to enhance antenna bandwidth.
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This document explains how to make a basic micro strip antenna (Balanis, 2015). Patch is used for the suggested antenna, and copper self-adhesive tape is used for the ground. The simulation results are shown, including the reflection coefficient, gain, and efficiency. Wearable computer system technology is rapidly evolving in order to improve the quality and efficiency of human existence by offering a flexible mobile system. A wearable system's use, functionality, durability, safety, and comfort have all become critical requirements. Health monitoring activities in the medical field, surveillance in military units, and sickness prevention and citizen medicine in the healthcare sector have all been established using the intelligent clothing, transmission of information, and communication system. Portable electronic gadgets have become an integral aspect of modern life. Modern mobile phones are often carried throughout the day, and they may be used for more than simply making phone conversations; they can also be used for internet access, multimedia, a personal digital assistant, and GPS navigation. This kind of “always on” and “always connected” state is a first step toward the ubiquitous computing paradigm. A person will likely carry a variety of gadgets and sensors in the future, including medical sensors, that are continually communicating with each other and the outside environment. It is critical to deliver this functionality in the least intrusive manner feasible. Wearable electronics and antennas are a critical technology for achieving this objective. The 2.45 GHz ISM unlicensed band is used for the development of wearable antennas because to its almost universal availability. Wearable antennas must be concealed and have a low profile for the user's comfort (DicCbshfsE et al., 2011; Kumar Singh et al., 2014).
This necessitates the antenna components' probable incorporation into daily apparel. Because it can be made conformal for incorporation into clothes, the microstrip patch is a good contender for any wearable application. In this publication, the authors report the design, development, and evaluation of flexible rectangle shaped microstrip wearable antennas for Bluetooth applications, which is similar to their prior research on circular disc antennas. In this study, four antennas are studied; antenna 1 uses wash cotton (textile material used in Bermuda manufacturing) fabric as its dielectric material, whereas antenna 2 uses curtain cotton fabric. The dielectric materials utilized in antennas 3 and 4 are polyester and polyester mixed cotton (65:35) fabric fabrics. Copper is used for the conducting portions in all four examples (Salonen and Rahmat-Samii, 2006; Kannadhasan and Nagarajan, 2022).
When these individual wearable antennas are held in the °at position, theoretical and experimental data on impedance characteristics are provided. For the purpose of studying radiation properties, antennas 1, 2, and 3 are evaluated. In an on-body setting, however, it is difficult to maintain the wearable antenna straight all of the time, as it bends often owing to body motions. As the antenna's resonant length changes, the bending may change its performance characteristics. As a result, an experimental research using at least one of the antennas (antenna 3) is carried out to explore the effects of antenna bending on performance attributes such as resonant frequency, return loss, impedance bandwidth, gain, and radiation patterns. Characteristics were investigated. The global positioning system (GPS) is a satellite-based navigation system that gives position and timing data at outdoor locations. GPS communication, on the other hand, is unable to offer service at an inside site. As a result, RFID communication must be employed to transmit GPS data in indoor locations. In this research, an all-textile antenna for GPS and RFID applications is incorporated into a military beret. Dual modes are used by the planned all-textile antenna, which has two ports (Hearle and Morton, 2008; Gupta, Sankaralingam, and Dhar, 2010). A ring patch with four shoring pins is meant for RFID applications with a monopole-like radiation characteristic at 915MHz, whereas a truncated patch is suited for GPS applications with a broadside radiation pattern with LHCP at 1.575GHz.