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A compact VHF/UHF ultrawideband discone antenna with consistent patterns is proposed in this article. The proposed antenna consists of a disk, a modified cone, an inverted cone, four shorting probes, and two sleeves. To improve the radiation angular distortion at high frequencies, two sleeves are inserted into the discone antenna. Higher-order modes are suppressed, and ultrawideband consistent patterns are obtained without antenna size increasing. An inverted cone and four shorting probes are introduced to achieve broadband and profile reduction. An antenna prototype is fabricated and measured. The proposed antenna possesses consistent patterns in a 11.36:1 bandwidth. The pattern nulls is improved by 26.1 dB. The antenna occupies a cylindrical volume of 0.227 λ0 (D) and 0.096 λ0 (H). It is a competitive candidate for future in-vehicle communication systems.

In this study, a broadband Radio Frequency (RF) energy harvester implementation is presented. The system uses a broadband discone antenna, which can operate efficiently in a broad frequency spectrum, including LTE, DCS 1800 and UMTS 2100 cellular frequency bands. The system is able to harvest energy from various electromagnetic field sources, thus has the potential to efficiently charge a storage energy element in a short time. The prototype broadband RF energy harvester was tested in the laboratory and also in a typical urban environment.

In this paper, the design and construction of an online non-invasive noninvasive partial discharges localization system is presented; it is integrated by four equal discone antennas with a wideband of 30 MHz to 1.2 GHz and a central frequency of 615 MHz connected to a four-channel high-resolution digital oscilloscope. The obtained electromagnetic signals are processed in a personal computer using Wavelet Transform and Fast Fourier Transform to reduce electromagnetic noise and identify the source of the PD respectively. Additionally, a spherical algorithm for spatial localization in R super( 3) is used. High-voltage laboratory and in situ measurements are reported.

In this paper the design and construction of an online non-invasive noninvasive partial discharges (PD) localization system is presented; it is integrated by four equal discone antennas with a wideband of 30 MHz to 1.2 GHz and a central frequency of 615 MHz connected to a four-channel high-resolution digital oscilloscope. The obtained electromagnetic signals are processed in a personal computer using Wavelet Transform and Fast Fourier Transform (FFT) to reduce electromagnetic noise and identify the source of the PD respectively. Additionally, a spherical algorithm for spatial localization in R3 is used. High-voltage laboratory and in situ measurements are reported.

A Digital Video Broadcast Terrestrial (DVB-T) based passive radar requires the development of a dedicated antenna array that performs satisfactorily over the entire DVB-T band. The array should require no mechanical adjustments to inter-element spacing to correspond to the DVB-T carrier frequency used for any particular measurement. This paper describes the challenges involved in designing an antenna array with a bandwidth of 450 MHz. The design procedure is discussed and a number of simulated array configurations are demonstrated. The final configuration of the array will be shown as well as simulations of the expected performance over the desired frequency span. (6 pages)