Showing papers on "Dielectric resonator antenna published in 2011"

Wireless energy transfer for vehicles

Abstract: A vehicle powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply. The wireless receiver includes a load configured to power the drive system of a vehicle using electrical power, and a second electromagnetic resonator adapted to be housed upon the vehicle and configured to be coupled to the load, wherein the second electromagnetic resonator is of substantially different size from the first electromagnetic resonator, wherein the second electromagnetic resonator configured to be wirelessly coupled to the first electromagnetic resonator to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator, and a second electromagnetic resonator adapted to be housed upon the vehicle and comprising an inductive loop and configured to be coupled to the load via a capacitive network comprising at least one capacitor in series with the inductive loop and one capacitor in parallel with the inductive loop.

Wireless energy transfer with variable size resonators for medical applications

Abstract: A medical device-powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply. The wireless receiver includes a load configured to power an implantable medical device using electrical power, and a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, wherein the second electromagnetic resonator is configured to be wirelessly coupled to the first electromagnetic resonator to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator, the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance.

Wireless energy transfer with resonator arrays for medical applications

Abstract: A medical device-powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply. The wireless receiver includes a load configured to power the medical device using electrical power, and a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, at least one other electromagnetic resonator configured with the first electromagnetic resonator and the second electromagnetic resonator in an array of electromagnetic resonators to distribute power over an area, wherein the second electromagnetic resonator is configured to be wirelessly coupled to the array to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator.

Wideband circularly polarized hybrid dielectric resonator antenna

Abstract: The present invention provides a dielectric resonator antenna comprising: a dielectric resonator; a ground plane, operatively coupled with the dielectric resonator, the ground plane having four slots; and a substrate, operatively coupled to the ground plane, having a feeding network consisting of four microstrip lines; wherein the four slots are constructed and geometrically arranged to ensure proper circular polarization and coupling to the dielectric resonator; and wherein the antenna feeding network combines the four microstrip lines with a 90 degree phase difference to generate circular polarization over a wide frequency band.

Wireless energy transfer with variable size resonators for implanted medical devices

Abstract: A medical device-powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply. The wireless receiver including a load is configured to power the medical device using electrical power, and a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, wherein the second electromagnetic resonator is configured to be wirelessly coupled to the first electromagnetic resonator to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator, the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance.

Wireless energy transfer with multi resonator arrays for vehicle applications

Abstract: A vehicle powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply. The wireless receiver includes a load configured to power the drive system of a vehicle using electrical power, and a second electromagnetic resonator adapted to be housed upon the vehicle and configured to be coupled to the load, at least one other electromagnetic resonator configured with the first electromagnetic resonator and the second electromagnetic resonator in an array of electromagnetic resonators to distribute power over an area, wherein the second electromagnetic resonator is configured to be wirelessly coupled to the array to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator.

Rectangular Dielectric Resonator Antennas With Enhanced Gain

Abstract: Rectangular dielectric resonator antennas were designed to operate at high-order modes to achieve enhanced gain. A simple model was developed to predict the radiation patterns of the higher-order modes. Prototypes designed at 11 GHz showed gains of up to 5 dB above those obtained by the fundamental mode.

Band-Notched UWB Antenna Incorporating a Microstrip Open-Loop Resonator

Abstract: Ultrawideband (UWB) systems require band notch filters in order to prevent sensitive components, within the front-end of the receiver, from being overloaded by strong signals. Recently, it has been shown that these filters can be integrated into the UWB antenna, to great advantage. This communication presents a new method for forming a notch band within the frequency response of a UWB antenna. An open loop notch band resonator is located on the back of the substrate, used to support the UWB monopole. The act of separating the resonator from the antenna means that they can now be designed in isolation, using the standard approach described in the literature, and then combined. A prototype was constructed and good agreement has been obtained between simulation and measurement. The radiation patterns are consistent over the frequency range of interest.

Design of the Millimeter-wave Rectangular Dielectric Resonator Antenna Using a Higher-Order Mode

Abstract: At millimeter-wave (mm-wave) frequencies, the size of the dielectric resonator antenna (DRA) may be too small to fabricate precisely. To relax the precision problem of fabrication, it is proposed to obtain a larger DRA by designing it with its higher-order mode. In this paper, the rectangular mm-wave slot-fed DRA excited in a higher-order mode is investigated systematically. It is found that when the slot is centrally located beneath the DRA, a TEpqr mode of the DRA can be excited only when all of the indices p, q, r are odd numbers. The aspect ratio of the DRA that gives a single (higher-order) TE11ry -mode operation is found. Like the fundamental TE111 mode, the higher-order TE11r modes have broadside radiation patterns. To validate our results, two DRAs were designed to operate in the higher-order TE115 and TE119 modes. In each case, the reflection coefficient, radiation pattern, and antenna gain are studied, and reasonable agreement between the measured and simulated results is observed. The effect of fabrication error on the frequency shift of the DRA was also studied. A design rule for minimizing the frequency shift is suggested. The results should be useful for practical designs of the mm-wave DRA.

UWB Dielectric Resonator Antenna Having Consistent Omnidirectional Pattern and Low Cross-Polarization Characteristics

Abstract: A new simple compact monopole type dielectric resonator antenna (DRA) for ultrawideband (UWB, 3.1-10.6 GHz) applications is presented. The design combines the advantages of small size DRA and thin planar monopole antennas. The design provides high-radiation efficiency, consistent omnidirectional characteristics, and low cross polarization within the entire band. The antenna size is 15 × 33 mm2 with 5.08 mm thickness. The dielectric resonator (DR) is shaped to house the excitation feed and the dielectric substrate is cut to house the DR. The coplanar waveguide is used to feed the antenna.

Millimeter-Wave High Radiation Efficiency Planar Waveguide Series-Fed Dielectric Resonator Antenna (DRA) Array: Analysis, Design, and Measurements

Abstract: A low cost general architecture for a substrate integrated waveguide (SIW) series-fed dielectric resonator antenna (DRA) array, formed by two different slot polarizations, is proposed. In addition, a novel, simple, and generic transmission line (T.L.) circuit model, along with a fast and generic formulation for the new linear array antenna, is developed. The model can be used for reflection coefficient and radiation pattern (gain) calculations. The experimental data from two linear array modules, operating at the millimeter-wave band, are used to verify the simulated results of HFSS and the proposed model results. The measured radiation pattern for a 4 t 1 SIW-DRA array demonstrates a broadside beam with a radiated gain of 11.70 dB over an operating impedance bandwidth of 4.70%. Moreover, the simulated radiation efficiency is more than 90%.

Hybrid ultrawideband dielectric resonator antenna and band-notched designs

Abstract: A novel dielectric resonator antenna (DRA) is proposed for ultrawideband (UWB) applications, where a simple rectangular dielectric resonator is excited by a bevel-shaped patch connected to a coplanar waveguide (CPW) feeding line. It is found that the bandwidth of the resonant modes can be expanded by using a CPW-fed ground and bevel-shaped patch, and thus a UWB performance can be achieved. Experimental and numerical results were carried out, showing a good agreement. The measured results demonstrate that the proposed DRA achieves an impedance bandwidth more than 3:1, covering the frequency range from 3.1 to 10.6 GHz, which is suitable for UWB applications. Furthermore, to minimise the potential interferences between the UWB system and narrowband systems, such as world interpretability for microwave access and WLAN, UWB DRAs with single band-notched and dual band-notched characteristics were designed, fabricated and measured. The measurement results show good performances in terms of VSWR, antenna gain and radiation pattern. With these features, the proposed antennas are expected to be good candidates in various UWB systems.

A Cross-Shaped Dielectric Resonator Antenna for Multifunction and Polarization Diversity Applications

Abstract: This letter proposes a multifunction cross-shaped dielectric resonator antenna (DRA) with separately fed broadside circularly polarized (CP) and omnidirectional linearly polarized (LP) radiation patterns. These distinct radiation patterns are achieved in overlapping frequency bands by exciting two different modes in a single dielectric resonator (DR) volume. This letter also investigates the effect of the feeding geometry on the mutual coupling between the modes and concludes that an asymmetric feeding degrades the orthogonality of the modes and thus increases the interport coupling coefficient. By using a symmetric feeding, the coupling coefficient can be significantly reduced to below - 30 dB in the frequency band common to both operation modes. The experimental results show a good agreement with simulation and demonstrate a broadside CP operation over a bandwidth of 6.8%, which overlaps with the omnidirectional LP impedance bandwidth of 38.5%. The proposed antenna could be used not only as multifunction, but also as polarization diversity antenna due to the overlapping dual-feed CP and LP operation.

Loss Dependence on Geometry and Applied Power in Superconducting Coplanar Resonators

Abstract: The loss in superconducting microwave resonators at low-photon numbers and low temperatures is not well understood but has implications for achievable coherence times in superconducting qubits. We have fabricated single-layer resonators with a high quality factor by patterning a superconducting aluminum film on a sapphire substrate. Four resonator geometries were studied with resonant frequencies ranging from 5 to 7 GHz: a quasi-lumped element resonator, a coplanar strip waveguide resonator, and two hybrid designs that contain both a coplanar strip and a quasi-lumped element. Transmitted power measurements were taken at 30 mK as a function of frequency and probe power. We find that the resonator loss, expressed as the inverse of the internal quality factor, decreases slowly over four decades of photon number in a manner not merely explained by loss from a conventional uniform spatial distribution of two-level systems in an oxide layer on the superconducting surfaces of the resonator.

Compact and Multiband Dielectric Resonator Antenna With Pattern Diversity for Multistandard Mobile Handheld Devices

Abstract: A compact multiband antenna system using a dielectric resonator antenna (DRA) is presented in this paper. Designed to be integrated in a tablet, it is not only heavily miniaturized (λ0/15×λ0/38×λ0/94 at 800 MHz), but also able to cover three frequency bands for different wireless applications (DVB-H, WiFi and WiMAX). Since a reconfigurable radiation pattern can result in an improved quality and reliability of wireless links, two DRAs have been integrated to implement this feature on the three frequency bands. These improvements are demonstrated by the presentation of the correlation coefficient and the effective diversity gain, both measured in a reverberation chamber. The experimental measurements are in very good agreement with the simulated ones. Good overall performances are obtained, and the requirements of all three applications are perfectly met. Moreover, the antenna operative frequencies are independent of the ground plane dimensions, making this system a very good candidate for all kinds of mobile devices.