In this research work, a multibeam antenna which is a combination of a beamformer network (BFN) and a linear array antenna, has been designed. A Rotman lens has been chosen as beamformer network and Vivaldi antennas have been selected for constructing array antenna. The Substrate Integrated Waveguide (SIW) was used for implementing Rotman lens. After explanation the structure of Substrate integ...

Because of special structure, a dual reflector antenna has beam rotation capability in azimuth and elevation directions. In this structure, the antenna beam can be placed in any point in the space by mechanical movement of twist reflector which it is the most important ability of the antenna. Due to the antenna structure, if the polarization of incident wave is linear, it is expected that the p...

In this paper two linear arrays including a linear 1×4 and a planar 2×2 of microstrip patch and half-mode substrate integrated waveguide (SIW) cavity hybrid antenna are introduced and investigated. These are simply implemented using low cost single layer printed circuit board (PCB) process. The array element consists of a rectangular microstrip patch with appropriate dimensions in the vicinity ...

In this paper we present a deterministic analysis of an online scheme for learning very general classes of nonlinearly parametrized decision regions. The only input required is a sequence ((xk; yk))k2Z+ of data samples, where yk = 1 if xk belongs to the decision region of interest, and yk = 1 otherwise. Averaging results and Lyapunov theory are used to prove the stability of the scheme. In the ...

We study the contact between nonlinearly elastic bodies by variational methods. After the formulation of the mechanical problem we provide existence results based on polyconvexity and on quasiconvexity. Then we derive the Euler-Lagrange equation as a necessary condition for minimizers. Here Clarke’s generalized gradients are the essential tool to treat the nonsmooth obstacle condition.

Polynomially structured low-rank approximation problems occur in • algebraic curve fitting, e.g., conic section fitting, • subspace clustering (generalized principal component analysis), and • nonlinear and parameter-varying system identification. The maximum likelihood estimation principle applied to these nonlinear models leads to nonconvex optimization problems and yields inconsistent estima...

The goal of this study is to detect linear and nonlinear causal pathways toward climate change as measured by changes in global mean surface temperature sea level over time using a data-based approach contrast the traditional physics-based models. Monthly data on potential factors, including greenhouse gas concentrations, sunspot numbers, humidity, ice sheets mass, coverage, from January 2003 D...

A Rectangular Dielectric Resonator Antenna (RDRA) is theoretically analyzed using the Conventional Dielectric Waveguide Model (CDWM), numerically simulated using the High Frequency Structure Simulator (HFSS) based on the Finite Element Method (FEM) software package and experimentally investigated with the consideration of the fundamental mode TE 111. Antenna parameters under investigation inclu...

A low cross-polarization slot array antenna in the narrow wall of ridge waveguide is presented. A non-angled slot which is created in the narrow wall of the ridge waveguide is considered to be used as radiating resonant slot. The normalized resistance and normalized reactance curves are presented for design purposes. A six element slot array waveguide antenna with ridges on its narrow wall is t...