In this paper, a multiband antenna using a novel fractal design is presented. The antenna structure is formed by inscribing a hexagonal slot within a circle. This base structure is then scaled and arranged within the hexagon along its sides without touching the outer structure. The proposed CPW fed, low profile antenna offers good performance in the 1.65 – 2.59 GHz, 4.16 – 4.52 GHz and 5.54 – 6...

Schottky diodes are fabricated on n-Aluminium Gallium Arsenide / Gallium Arsenide (n-AlGaAs/GaAs) high-electron-mobility-transistor (HEMT) structure due to availability of high electron mobility and capability of fast switching performance. The processing steps used in the fabrication are the conventional steps used in standard GaAs processing. The ohmic and Schottky contacts of Schottky diodes...

In this paper, different configurations of transmission lines loaded with stepped impedance resonators (SIRs) are reviewed. This includes microstrip lines loaded with pairs of SIRs, and coplanar waveguides (CPW) loaded with multi-section SIRs. Due to the high electric coupling between the line and the resonant elements, the structures are electrically small, i.e., dimensions are small as compar...

I want to start by congratulating Professors Chandrasekaran, Parrilo and Willsky for this fine piece of work. Their paper, hereafter referred to as CPW, addresses one of the biggest practical challenges of Gaussian graphical models—how to make inferences for a graphical model in the presence of missing variables. The difficulty comes from the fact that the validity of conditional independence r...

Four-dimensional colliding plane wave (CPW) solutions have played an important role in understanding the classical non-linearities of Einstein’s equations. In this note, we investigate CPW solutions in 2n+2–dimensional Einstein gravity with a n+1-form flux. By using an isomorphism with the four-dimensional problem, we construct exact solutions analogous to the Szekeres vacuum solution in four d...

We have measured the magnitude and phase responses of a photoreceiver to 110 GHz using a calibrated electro-optic sampling system. The frequency range of the calibration is limited only by our 1 mm coaxial connectors. In this paper, we present a method for accurately characterizing the response of a commercially available photoreceiver to 110 GHz, nearly three times the bit rate of 40 Gb/s opto...

The physical environment is becoming more and more saturated with computing and communication entities that interact among themselves, as well as with users: virtually everything will be enabled to source information and respond to appropriate stimuli. In this technology-rich scenario, real-world components interact with cyberspace via sensing, computing and communication elements, thus driving...

I want to start by congratulating Professors Chandrasekaran, Parrilo and Willsky for this fine piece of work. Their paper, hereafter referred to as CPW, addresses one of the biggest practical challenges of Gaussian graphical models—how to make inferences for a graphical model in the presence of missing variables. The difficulty comes from the fact that the validity of conditional independence r...