Microstrip antenna theory and application xidian university

#Microstrip antenna theory and application xidian university Patch

In contrast to stretchable antennas based on liquid metals, conductive textile, or conductive composites, the stretchable metal antennas exhibit enhanced radiation efficiency due to the low ohm loss.

#Microstrip antenna theory and application xidian university Patch

Compared to the dipole and loop antennas, the microstrip patch antennas showcase significantly improved on-bodyВ performance because the ground plane can help eliminate or reduce the effect from the underlying lossy tissues. As a result, the development of stretchable antennas and rectennas started to gain momentum recently. The combination of aВ RF antenna and rectifying circuit results in a rectifying antenna (rectenna) to harvest ambient RF energies for low-power flexible/stretchable electronics. On the other hand, far-field communication with a radiofrequency (RF) antenna can be leveraged for wireless data and energy communication at a much longer working distance.

However, its applications are limited by the short working distance. For instance, near-field communication (NFC) has been widely used in wireless epidermal electronic systems to monitor various physiologically relevant signals. Additionally, they can easily integrate the other commercial off-the-shelf (COTS) chips through a conventional soldering process to achieve extended capabilities for mass-production and commercialization.ДЄs an indispensable component in flexible/stretchable electronics, wireless technology allows wireless powering and data transmission in the resulting miniaturized, integrated systems. Compared to the intrinsically stretchable materials with various functionalities, conventional metal conductors (and semiconductors) with stretchable structures exhibit high performance comparable with modern electronics. Alternatively, the latter stretchable structures (e.g., serpentine or 3D structures ) allow the conventional metals to be stretched over tens of percent without damage. With direct relevance to wireless devices such as antennas, intrinsically stretchable conductors often explore conductive polymers, liquid metals, and conductive composites with low-dimensional nanofillers in a stretchable polymeric matrix. The former includes the intrinsically stretchable semiconductors, insulators, and conductors. The commonly used strategies in the design and fabrication of flexible/stretchable electronics rely on either intrinsically stretchable materials or stretchable structures. The integration of sensors and actuators with data communication and powering modules in this class of emerging electronics enables its applications in energy generator/storage, humanвЂ“machine interfaces, health monitoring, and clinical treatments. The flexibility in structural engineering combined with the coupled mechanicalвЂ“electromagnetic simulations, provides a versatile engineering toolkit to design stretchable microstrip antennas and other potential wireless devices for stretchable electronics.ДЇlexible/stretchable electronics attached to dynamically changing, curvilinear surfaces can still function properly upon various mechanical deformations, including stretching, bending, and twisting. The proposed stretchable microstrip antenna was demonstrated to communicate wirelessly with a transmitter (input power ofвЂ‰в€’вЂ‰3 dBm) efficiently (i.e., the receiving power higher thanвЂ‰в€’вЂ‰100 dBm over a distance of 100В m) on human bodies even upon 25% stretching.

The almost unchanged resonance frequency during deformations enables robust on-body wireless communication and RF energy harvesting, whereas the rapid changing resonance frequency with deformations allows for wireless sensing. Here, a hierarchically structured stretchable microstrip antenna with meshed patterns arranged in an arched shape showcases tunable resonance frequency upon deformations with improved overall stretchability. However, they often suffer from frequency detuning upon mechanical deformations thus, their applications are limited to wireless sensing with wireless transmission capabilities remainingВ elusive. As the key component of wireless data transmission and powering, stretchable antennas play an indispensable role in flexible/stretchable electronics.