the effects of steel wire patenting process parameters on very fine interlamellar spacing in the pearlitic steel wire were investigated and the optimized condition of the process was achieved. in this work, the initial nanopearlitic structure was obtained in a 0.72 wt% carbon steel wire before the wire drawing process. the results were the minimum interlamellar spacing of 35 nm and maximum ulti...

FPGA based signal processors are employed in a diverse range of signal processing applications for reasons of performance, economics, flexibility and power consumption. Software defined radios (SDR) are highly configurable hardware platforms that provide the technology for realizing the rapidly expanding futuregeneration digital wire less communication infrastructure. Many sophisticated signal ...

We have recently shown that metamaterials composed of three-dimensional gold helices periodically arranged on a square lattice can be used as compact "thin-film" circular polarizers with one octave bandwidth. The physics of the motif of these artificial crystals is closely related to that of microwave sub-wavelength helical antennas in end-fire geometry. Here, we systematically study the depend...

This paper summarizes our efforts to create a composite material with a mechanically tunable plasmon frequency at the microwave band. The permittivity of the composite changes sign at the plasmon frequency. Such composites, therefore, can be used as electromagnetic filters. Theoretically, an array of non-magnetic, metallic wire coils has been shown to have a plasmon behavior that is dependent o...

A subcell model for thin wires in the finite-difference time-domain (FDTD) method using modified telegraphers equations has been developed by Holland et al. In this paper we present an extension of their algorithm, which allows arbitrarily located and oriented wires with respect to the Cartesian grid. This is important to be able to accurately model wires that cannot be aligned to the Cartesian...

We investigate the ergodic secrecy capacity of a Multiple-Input Multiple-Output (MIMO) wire-tap channel, where the instantaneous Channel State Information (CSI) is available at both the legitimate receiver and the eavesdropper, but not at the source. We derive the perfectsecrecy capacity under a general ergodic fading process (with a continuous probability density function) and show that a circ...

The wireless communication serves the efficient information among two or more points wirelessly. Antenna is the main component in the communication, which radiates and receives the radio waves or in broad way. The antenna also plays a role of impedance matching device, which performs the matching of impedances like free-space & transmitter and receiver impedances at receiver end. The antennas c...

Dipole antenna is the simplest and widely used antenna in telecommunication applications which consists of two identical conductive metal wires. Dipole antenna performance is dependent on many parameters such as metal conductivity, length, radius of wire, surrounding medium, feeding point and etc. but, In this article, we are studying the effect of length and radius on the performance of these ...

Future base stations for Spatial Division Multiplex Access (SDMA) will utilize adaptive antenna arrays, capable of identifying the direction of the incoming signal and steering the transmitted beam in appropriate directions. The radiating elements that have been thus far considered for building the antenna array are typically wire dipoles or microstrip patches. This tutorial paper describes a n...