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A novel, substrate-free, Frequency-scaled Ultra-wide Spectrum Element (FUSE) antenna has been designed and built. Measured results from a 17×16 prototype demonstrate experimental validation for a scalable, low-profile, and dual-polarized phased array that has 7:1 bandwidth ratio, scanning 45 degrees in elevation at all azimuth with a VSWR lower than 2, and has better than −17 dB cross-polarization...
The capability of relatively high-speed short-range communications of Autonomous Underwater Vehicles (AUVs) in underwater scenarios, for example, for communication between vehicles or when the AUV is approaching a docking station for downloading of data gathered during a survey mission, is becoming a relevant application in the context of sea exploration and mining. In this paper the analysis of the...
It is introduced that a new type of portable PD measurement system has been developed especially for the periodic inspection tour of power cable circuit in operation. Based on the causes of PD produced in cable and its accessories various PD sensors such as HFCT, UHF, AE and TEV have also been developed for site PD detection application. Therefore, this new type PDM equipment is designed and made...
Due to the massive data traffic in wireless networks, energy consumption has become a crucial concern, especially with the limited power supply of the mobile terminals and the increasing emission of the cellular industry. In this context, we study the energy efficiency (EE) of MIMO spectrum sharing cognitive radio (CR) systems under power and interference constraints. We present an energy-efficient...
This paper shows the usefulness of soft computing techniques in antenna parameters calculation, design and optimization. Since long time, different soft computing techniques have been drawn attention of researchers, such as Artificial neural network (ANNs), Fuzzy Logic, Radial basis function neural network (RBFNNs) and evolutionary algorithms (EAs). Some popular EAs are Genetic algorithm and its variants,...
An effective probe compensated near-field - far-field (NF-FF) transformation with spherical scanning for an offset mounted long antenna, requiring a number of NF data that is minimum and equal to that needed in a centred configuration, is developed in this work, by applying the nonredundant sampling representations of the electromagnetic field and modelling the antenna under test (AUT) by a prolate...
This paper presents the effect of dimensions, spacing, periodicity and shapes of Reactive Impedance Surface (RIS) elements on resonating frequency of a suspended 2 × 2 MSA antenna array designed on a RIS loaded FR4 substrate. RIS consists of 13 × 13 square patch array with each patch of side 4mm and 1mm inter-element spacing. Elements of MSA array are fed through a feed line network which is fed by...
The Terrain Observation by Progressive Scans (TOPS) mode solves the problems existing in the conventional ScanSAR mode by steering the antenna along the azimuth direction. However, the antenna steering introduces a serious azimuth signal aliasing both in time-domain and frequency-domain, thus traditional imaging algorithms are not available for the TOPS mode. In order to solve the azimuth signal aliasing,...
A broadband substrate integrated dielectric resonator antenna (BSIDRA) is presented and investigated experimentally. The proposed BSIDRA consists of a substrate integrated dielectric resonator (SIDR) fed by a substrate integrated waveguide with an exciting slot. Dual resonances of the SIDR and the exciting slot radiator are merged to expand the antenna bandwidth. To validate the proposed concept,...
A novel compact Ultra-wideband (UWB) microstrip patch antenna using planar metamaterial structures is proposed. The metamaterial microstrip antenna has two layers consists of a meshed top patch and a patterned ground plane. The inductances and capacitances coupled due to the ground plane and patterned radiating patch leads to the left handed behavior of the metamaterial. The proposed antenna which...
This paper proposes a new method to suppress azimuth ambiguities for synthetic aperture radar (SAR) images. This thought derives from sidelobes suppression in SAR images, by comparing the values of two or more versions of normalized SAR images, which are obtain after different weighting functions for the same image, we choose the minimum one as its final value, therefore the new image could have lower...
SAR instruments with multiple transmit/receive channels allow for a variety of operation modes. The trade-space includes the instrument and antenna parameters designed to enable various operation modes. These are utilized to achieve a required SAR performance derived from the mission and user requirements. Finding a solution in this multi-dimensional trade space is not trivial and often involves the...
This paper presents design of a subwavelength patch antenna using epsilon negative metamaterial. Firstly, the metamaterial is designed at resonant frequency of reference rectangular patch antenna at 5.2 GHz and then this designed metamaterial is applied underneath the reference patch antenna. Addition of ENG metamaterial underneath the patch antenna decreases its resonant frequency. Simulation results...
In this paper a small size wideband planar inverted-F antenna (PIFA) is proposed which operates at 4G LTE (2.3–2.4 GHz) and (2.5–2.7 GHz), Bluetooth/WLAN (2.4–2485 GHz) and WiMAX (3.4–3.6 GHz) range. The proposed antenna has many advantages like small size and wide operation bandwidth. The antenna portion has dimensions as 20mm * 18mm and the overall dimensions are 44mm * 25mm * 0.8mm which can be...
This paper presents an approach for a fast evaluation of the bandwidth performance of reflectarray by incorporating the simulated reflectarray element phase response into the theoretical formulation of [1].
It has become apparent that current fronthaul technology cannot be simply extended to meet the projected demands of 5G and beyond mobile systems. This current technology, based on the transport of sampled radio waveforms, has been the preferred option, with analog radio over fiber reserved to relatively niche application scenarios. However, for future systems, it is recognised that different functional...
A kind of V-shape-meander-line reconfigurable electromagnetic band-gap (EBG) structure is designed in this paper. The proposed EBG structure is fabricated and measured. It is found that miniaturization and frequency reconfigurability of EBG structure can be realized.
Optimization of a Fabry-Perot cavity antenna by particle swarm optimization algorithm is presented. The objective of this work was to find the optimal transverse permittivity variation in a planar superstrate providing the maximum directivity bandwidth product. Additionally, a method to reduce the total optimization time is presented. The key antenna parameters of a near-optimal solution, such as...
An electrically small passive UHF-RFID tag based on a square-shaped split ring resonator antenna is presented. An analytical formulation of the radiation properties and the chip impedance matching is provided. A tag prototype of size 31 mm × 31 mm (λ0/11 × λ0/11) is designed and fabricated. The simulated and measured results are in good agreement with the theoretical analysis and the measured read...
A novel differentially fed dual-band planar antenna operating at the medical implant communication service (MICS) band (402–405 MHz) and the industrial, scientific and medical (ISM) bands (2400–2480 MHz) is presented. The measured 10-dB differential reflection coefficient bandwidth is 389–419 MHz (7.4%) at the lower band and 2395–2563 MHz (6.6%) at the upper band, respectively. The volume of the implantable...
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