The ability to pattern planar and freestanding 3D metallic architectures at the microscale would enable myriad applications, including flexible electronics, displays, sensors, and electrically small antennas. A 3D printing method is introduced that combines direct ink writing with a focused laser that locally anneals printed metallic features "on-the-fly." To optimize the nozzle-to-laser separa...

Optical antennas can enhance the coupling between free-space propagating light and the localized excitation of nanoscopic light emitters or receivers, thus forming the basis of many nanophotonic applications. Their functionality relies on an understanding of the relationship between the geometric parameters and the resulting near-field antenna modes. Using scattering-type scanning near-field op...

This report summarizes the results of our evaluation of antennas of contactless and dual interface smartcards and our ideas for user-switchable NFC antennas. We show how to disassemble smartcards with contactless capabilities in order to obtain the bare chip module and the bare antenna wire. We examine the design of various smartcard antennas and present concepts to render the contactless inter...

A low-cost and portable vector network analyzer (VNA) which covered operating frequency between 1MHz to 3GHz is used for vector reflection coefficient and standing wave ratio (swr) of the various microstrip antennas. This paper presents measurements of various ultra wideband (uwb) microstrip antennas for applications in biomedical field. Selection of antenna is an important key for detection of...

Abstracr We construct simal constellations for differential transmission with multiple basestation antennas. The signals are derived using the theory of fixed-point-free groups and are especially suitable for mobile cellular applications because they do not require the handset to have more than one antenna or to know the time-varying propagation environment. Yet we achieve full transmitter dive...

This paper proposes a bandwidth-eecient fading-resistant transmission scheme which implements transmitter diversity using L antennas at the base station. When the antennas are spaced suuciently far apart, the transmission from each antenna undergoes a diierent degree of fading. These transmissions are coordinated to mitigate the eeects of Rayleigh fading and the mobile receiver can recover the ...

The antenna is a critical component of the communication system. used in wireless for signal transmission and reception over long distances. There are numerous sorts antennas, such as wire traveling wave reflector microstrip so on. application antennas determined by antenna's attributes well frequency range operation. As result, it vital to understand behavior wide operations select optimum app...

analysis of aperture-coupled microstrip antennas with a superstrate using space domain closed form greens functions is presented. integral equations are derived from applying the boundary conditions on the radiating patch, across the aperture, and on the microstrip feedline. the computation of space domain greens functions is performed using the closed-form. the solution of the integral equatio...

Phased antenna arrays of dipoles are widely used in ultrahigh field (UHF) magnetic resonance imaging for creating the controllable radio frequency (RF) distributions a human body. Due to safety and quality reasons each individual channel array should be decoupled-electromagnetically isolated from others. The required number channels is large some techniques dipole antennas located close proximi...