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A novel fractal planar inverted F antenna (F-PIFA) based on the self affinity design is presented in this paper. The procedure for designing a Fractal Planar Inverted F Antenna is explained and the 2nd iteration of Sierpinski Carpet is chosen to use in mobile phones. The F-PIFA has a total dimension 27 mm ?? 27 mm are designed and optimized in order to receive GSM (global system for mobile communication)...
In our modern world, there are a number of wireless communication systems and broadcasting services which must be integrated into vehicles. However, there is very limited space for a lot of gadgets, so the need for low-cost, compact but highly efficient antennas without the need of an amplifier is essential. This document describes a low-cost, small and rugged triple-service patch antenna which features...
In this paper, we present the performance of a dual-band textile CPW antenna under different bending and crumpling conditions. The performance of the antenna is presented together with an electromagnetic band gap material (EBG) to improve the wearable antenna performance. The input impedance and radiation pattern are investigated based on numerical and experimental methods at 2.45 GHz and 5.8 GHz.
Some general formulae for the properties of single tuned electrically small antennas are reviewed. For many types of such antennas, their impedance around resonance behaves like either a series tuned or parallel tuned LCR resonator. The effect of deliberately increasing Ohmic losses in order to improve bandwidth is investigated. While the impedance bandwidth can improve, the ratio of radiated power...
In this paper we present a Fabry-Perot type of design, involving a microstrip array covered by a 14??0 ?? 14??0 superstrate that realizes a directivity of 32 dB when excited by an array of 25 microstrip patches. We show that the directivity of the array can be enhanced by an additional 2 dB by using a two-layer superstrate. We present the radiation patterns for the two cases to show that the sidelobe...
A small compact microstrip patch antenna with C-shaped slot is presented. It is developed to operate in the WiMax frequency range of 2.5-2.69 GHz. The antenna presents a size reduction of about 37% when compared to a conventional microstrip patch.
In this paper, the properties of cylindrical high-permittivity dielectric particles are studied. The refractive index is calculated with a parameter retrieval method and a Fourier transform method. It is shown that the periodic particles have low losses, while being non-resonant and broadband. Furthermore, the refractive index can be adjustable according to the dimensions of the particles. Application...
In this paper, we present a further investigation of microstrip-fed planar UWB monopole antennas using both the numerical and experimental approaches. The focus is on the characteristic mode analysis and the optimisation of the monopole design in term of its size and S11 performance. A comparison of elliptical and circular monopoles is also conducted.
In this paper, a new design of miniature, multiband slot antenna is presented. The slot structure of the proposed antenna is based on the 3rd iteration of the Moore space-filling geometry, which is a closed variant of the conventional Hilbert space-filling curve. The slot structure is constructed on the ground plane side of a dielectric substrate. The slot antenna is fed by a 50 ?? microstrip line,...
This paper presents a novel reconfigurable handset antenna for use in current and future wireless communication systems. The construction of the antenna is simple, allowing independent and versatile dual frequency and bandwidth reconfiguration, using simple external matching circuits. The antenna incorporates two metal elements which are capacitively coupled to excite resonant modes within the handset...
A new method of meandered variable pitch angle printed Quadrifilar Helix Antenna (MVPQHA) is described. This type of antenna helps in reducing the size of the printed quadrifilar helix antenna (PQHA) and makes the bandwidth of the antenna broader. The new type of antenna is compared with other existing types of printed quadrifilar helix antenna in terms of size, return loss and bandwidth.
This paper investigates the possibility of designing and fabricating microwave antennas using metallic nanomaterials. Specifically, we will consider modifying the structure of conventional designs including dipoles, loops and apertures. FDTD simulations are used to examine these modified structures. Due to the prohibitive computational requirements of modelling nanoscale objects on a millimetre scale,...
A double-loop antenna is proposed for mobile satellite communications antennas having linear polarized wave. The antenna consists of two loop antennas concentrically located on a dielectric substrate with a reflector and these antennas act as dominant and second mode resonant frequencies. Firstly, characteristics of each loop antenna are calculated to investigate fundamental radiation characteristics...
In this paper we describe the design, manufacture and performance of an electrically thin (0.15 ??) dynamically adaptive Salisbury screen absorber. The structure is backed by a high impedance surface which is constructed on a 250 ??m thick liquid crystal substrate. The shift in the resonant frequency of the radar absorber is obtained by exploiting the voltage dependent anisotropic property of nematic...
A plaster antenna for 2.45 GHz applications is presented. Measurement results for different use cases are given, and bending effects are examined. The proposed structure exhibits a 6 dBi on-body gain, and covers the 2.4-2.5 GHz ISM band in all use cases. The effect of bending the antenna on the SAR has been investigated by simulations. The antenna is suitable for medical applications.
A single layer, single feed, multi frequency, compact rectangular printed antenna is proposed. Resonant frequency has been reduced drastically by cutting unequal rectangular slots at the edge of the patch along with two tiny circular slots created inside the patch to improve return loss. Antenna size has been reduced by 64% with an increased frequency ratio (the ratio of second or higher resonant...
The paper continues investigations of antennas for the miner cardiac rhythm sensor. The sensor and the beacon are placed in the battery's box of a miner's lantern. Measurements of cardiac rhythm are based on measurements of reflected microwave energy. The mutual positioning of the battery's box with the sensor and human body is changed continually. Previous investigations have shown that a simple...
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