Design of Metamaterial Based Multilayer Antenna for Navigation/Wifi/Satellite Applications

Abstract

Wireless communication plays a vital role in transmitting information from one point to another. Wireless devices have to be smart, intelligent, compact in size, and cost effective to meet the demand of wireless communication. A multi-layered, Split Ring Resonator (SRR), negative permeability material inspired antenna has been designed, analyzed, fabricated, and measured. The developed antenna resonates at 1.13 GHz, 2.47 GHz, and 2.74 GHz frequencies with gain of 3.73 dBi, 6.18 dBi, 1.35 dBi, and bandwidth of 2.10%, 2.81%, and 2.09%, respectively. The structure utilizes FR4 material as a substrate. The engineered model has applications in navigation, WiFi, and satellite communication applications.

Particle-Attachment-Mediated and Matrix/Lattice-Guided Enamel Apatite Crystal Growth

“…Our study overcomes several technical challenges posed by the aqueous, protein-rich enamel matrix, 19 requiring invasive steps of sample preparation and dehydration necessary for electron imaging in high vacuum. 8 To avoid the inherent artifacts associated with classical techniques and to study mineral/matrix relationships in the developing enamel matrix at a nanoscale level, ultrathin enamel matrix preparations have been encapsulated between fewlayer graphene sheets, allowing for liquid-state atomic resolution matrix imaging using atomic resolution electron microscopy. There was no evidence of dissolution or phase transformation in our micrographs, suggesting that these images captured unperturbed events during the earliest stages of mouse amelogenesis.…”

“…Previous electron microscopic images of fixed enamel protein matrix had also demonstrated approximately 20nm diameter hollow and annular subunits, but these were part of an extensive network of similar structures that together formed the non-mineralized enamel protein matrix. [4][5][6]8 In the present study, immersion of unfixed pre-mineralization enamel matrix into the liquid cell and the atomic scale spatial resolution of our STEM resulted in the capture of these high-resolution micrographs of individual annular matrix subunits. The unique annular shape of these subunits may provide a structural template for mineral particle assembly to form higher ordered structures.…”

“…20,21 Previously, we have only observed the presence of electron-dense precipitates within the protein matrix in our organ culture studies. 4,5,6,8 Here we attribute our ability to resolve mineralization foci within the native matrix to the high resolution of our STEM and to the darkfield imaging mode employed. In our samples, electron-dense particles were frequently aligned to form rows of individual particles, and a lattice pattern extended beyond the boundaries of individual mineralization particles.…”

“…In previous studies we have identified the protein phase tightly associated with the enamel crystal surfaces as C-terminal fragments, while N-terminal fragments appeared to float freely in between maturing enamel crystals. 8 Others have proposed that cleavage of the C-terminal fragment from the polyproline-rich domain will render the amelogenin carboxy-terminus hydrophobic, 26 which would explain the self-assembled reticular networks on the growing enamel crystal surfaces as proline-rich self-assembled protein aggregates. Such proteindense self-assembled reticular networks in between individual enamel crystals would provide spacing during crystal growth and and bulk calcium phosphate precipitation.…”

“…4 visualized the functional role of enamel matrix subunit compartments during enamel crystal growth, 5,6 and demonstrated the role of posttranslational amelogenin processing and resulting changes in matrix assembly. 7,8 Recent studies using cryo-electron microscopy demonstrated the importance of amelogenin assemblies in the stabilization of mineral prenucleation clusters and their involvement in the formation of linear chains and needle-shaped mineral particles. 9 Other studies have provided evidence for the hierarchical organization of the amelogenin matrix, beginning with 4-6nm subunits within nanospheres of 15-25nm radii and resulting in self-assembly of microribbons of > 100nm length.…”