in recent years, need to increase the convenience of trips in railway vehicles causes that train operators and manufacturers focus on reducing the noise level which is sensed by passengers. in this paper, first the state of modeling acoustic noise in cab train is discussed and natural frequencies and acoustic mode shapes are derived and then formulation of acoustic pressure in the cab will be o...

The Ballistic Mis sile Defense System (BMDS) is a phased arrangement of equipment that is designed to engage a limited number of ballistic missiles launched against the United States and her allies. A phased system is one that changes its characteristics over time. Although a system does not modify its characteristics within a phase, when the system departs one phase and enters another, the sys...

In phased array antennas, the number of radiator rows is one of the important factors to minimizing both cost and weight. Therefore, the antenna tilt angles having relation with the element spacing are among the important design parameters. In this paper, the optimum tilt angles for several types of dipole planar arrays are investigated theoretically. To obtain optimum tilt angles, the directiv...

Photonic integration is very promising to bring down volume and weight of phased-array beamforming networks. In addition, photonics allows for increased functionality for widebandwidth systems. In this paper we demonstrate the feasibility of phase and amplitude control of a 16-element phased-array antenna with a single InP integrated circuit. The concept and design of an optical phase locked lo...

A chip-scale optical source with integrated beam steering is demonstrated. The chip was fabricated using the hybrid silicon platform and incorporates an on-chip laser, waveguide splitter, amplifiers, phase modulators, and surface gratings to comprise an optical phased array with beam steering across a 12° field of view in one axis. Tuning of the phased array is used to achieve 1.8°(steered axis...

ABSTRACT The single-phased power receivers, supplied to the industrial frequency, represent very inductive loads. These are connected to the three-phased network through the Steinmetz connection symmetrizing devices. Considering an experimental model which is reproducing in a small scale the real device, we have realized the designing of the control system, connected to the output interface of ...

We report a transducer structure tha t combines two orthogonal phased arrays which enable the real-time scanning of two orthogonal sectors. This biplane phased array is formed by partially dicing the opposite faces of a composite piezoelectric plate in orthogonal directions. Individual elements of the orthogonal arrays show broad radiation patterns close to the theoretical expectations for isol...