Survey of challenges, development, and potential tera-wave wearable antennas for wireless body area networks

Terahertz band has potential applications in healthcare applications and lot of advantages over other traditional bands like Industrial Scientific Medical Band (ISM: 2.4 GHz, 5.8 GHz), Medical Implant Communication System Band (MICS: 400 MHz), and UWB (3–10 GHz) because of non-invasive, non-ionization nature, high sensitivity for detecting changes in cells, tissues, and biomolecules, least harmful, compact antenna size, elevated data rate, wide bandwidth and scarcity of spectrum. Due to the short wavelength, the THz frequency can penetrate some non-polar and non-metallic materials. High-definition THz waves can easily scan images of opaque to transparent objects. THz radiation is becoming significant for detecting dangerous goods like viruses, explosives, pistols, chemicals, etc., because the maximum of the large molecules lies in the THz band. Implantation of THz antenna inside the body is feasible because of its compact size in nanometres. It also results in inexpensive substrate cost, ease of installation, light weight, and the least bulky. Significant challenges of THz antennas are a highly précised fabrication process required because of the tiny size, alignment errors in the multilayer structure, unstable gain and efficiency over a wide bandwidth, and high cross-polar radiation. This article explores the challenges of traditional healthcare antennas, reviews potential THz antennas and their applications in the medical field, and compares the performance of THz antennas.