Antenna 3D pattern measurement can be a tedious and time consuming task even for antennas with manageable sizes inside anechoic chambers. Performing onsite measurements by scanning the whole 4π [sr] solid angle around the antenna under test (AUT) is more complicated. In this paper, with the aim of minimum duration of flight, a test scenario using unmanned aerial vehicles (UAV) is proposed. A pr...

Автор рассматривает эстетическую природу телевидения, составляющие компоненты художественного образа, язык выразительных средств различных искусств и природную связь ТВ с кинематографом. The article examines the aesthetic nature of television, components artistic image, «language» expressive means arts and natural connection TV with cinema.

Background: Excessive and uncontrolled television watching by children predisposes them to some risks such as developmental, social and psychological disorders. Parents play an important role in nurturing their children and controlling the factors affecting their health. The aim of this study was to determine the impact of health education programs on parents’ supervision skills to contro...

A new design of coplanar waveguide (CPW)-fed antenna with circular polarization (CP) and excellent impedance matching is presented. In this design a pair of circular-shaped slits is applied to opposite corners of the slot for enhancing the impedance matching and realizes bandwidth of 134.43% across 2.98-15.20 GHz for VSWR≤2. Furthermore this structure exhibits axial ration bandwidth (ARBW) of 3...

an active antenna for transmitter application in s frequency band is designed and analyzed using harmonic balance technique which is based on the nonlinear model of active devices. in this active antenna, the amplifier is integrated with the radiator which is a rectangular patch antenna. this patch antenna is analyzed employing full-wave momentum method. by applying nonlinear model of transisto...

The requirement of wideband and compact devices is ever increasing in most communication systems. In addition, recent increases in the transmission and reception of information have created a need for broadband and low profile antennas. This necessity is particularly challenging in designing Radio Frequency (RF) products that demand these features at low RF bands. There are numerous situations ...

Mesospheric observations were obtained by the EISCAT UHF and VHF radars during the solar proton event of March 1990. We present the ®rst comparison of incoherent-scatter spectral measurements from the middle mesosphere using simultaneous, colocated observations by the two radars. VHF spectra observed with a vertical antenna were found to be signi®cantly narrower than model predictions, in agree...

The main idea of this paper is to determine the influence of the position and the angle of a tag in the reading of an RFID system, therefore we have developed two different experiments. In the first one, a model with a tag was moved perpendicular to two antennas fixed to a vertical support. In the second one, the same model was moved through two vertical supports with two RFID-UHF antennas each...

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