Showing papers on "Dielectric resonator antenna published in 2006"
Patent•
05 Jul 2006TL;DR: In this paper, the authors proposed an electromagnetic energy transfer device that includes a first resonator structure receiving energy from an external power supply, and a second resonance structure is positioned distal from the first, and supplies useful working power to an external load.
Abstract: The electromagnetic energy transfer device includes a first resonator structure receiving energy from an external power supply. The first resonator structure has a first Q-factor. A second resonator structure is positioned distal from the first resonator structure, and supplies useful working power to an external load. The second resonator structure has a second Q-factor. The distance between the two resonators can be larger than the characteristic size of each resonator. Non-radiative energy transfer between the first resonator structure and the second resonator structure is mediated through coupling of their resonant-field evanescent tails.
730 citations
TL;DR: Active optical feedback cooling to 135 ± 15 mK of a micromechanical resonator integrated with a high-quality optical resonator is demonstrated, allowing cooling to near the ground state that is required for quantum experiments—near 100 nK for a kHz oscillator.
Abstract: Micromechanical resonators, when cooled down to near their ground state, can be used to explore quantum effects such as superposition and entanglement at a macroscopic scale. Previously, it has been proposed to use electronic feedback to cool a high frequency (10 MHz) resonator to near its ground state. In other work, a low frequency resonator was cooled from room temperature to 18 K by passive optical feedback. Additionally, active optical feedback of atomic force microscope cantilevers has been used to modify their response characteristics, and cooling to approximately 2 K has been measured. Here we demonstrate active optical feedback cooling to 135 +/- 15 mK of a micromechanical resonator integrated with a high-quality optical resonator. Additionally, we show that the scheme should be applicable at cryogenic base temperatures, allowing cooling to near the ground state that is required for quantum experiments--near 100 nK for a kHz oscillator.
579 citations
Patent•
04 Oct 2006
TL;DR: In this paper, a plasma electrode-less lamp is described, which consists of an electromagnetic resonator and an electromagnetic radiation source conductively connected with the electromagnetic resonance, and a gas-fill vessel is formed from a closed transparent body, forming a cavity.
Abstract: Described is a plasma electrode-less lamp. The device comprises an electromagnetic resonator and an electromagnetic radiation source conductively connected with the electromagnetic resonator. The device further comprises a pair of field probes, the field probes conductively connected with the electromagnetic resonator. A gas-fill vessel is formed from a closed, transparent body, forming a cavity. The gas-fill vessel is not contiguous with (detached from) the electromagnetic resonator and is capacitively coupled with the field probes. The gas-fill vessel further contains a gas within the cavity, whereby the gas is induced to emit light when electromagnetic radiation from the electromagnetic radiation source resonates inside the electromagnetic resonator, the electromagnetic resonator capacitively coupling the electromagnetic radiation to the gas, which becomes a plasma and emits light.
162 citations
TL;DR: In this article, a circularly polarized rectangular stair-shaped dielectric resonator antenna (DRA) is presented, which is excited by a narrow rectangular slot and rotated 45/spl deg/ with respect to the sides of the DRA to generate circular polarization.
Abstract: A circularly polarized rectangular stair shaped dielectric resonator antenna (DRA) is presented. The DRA is excited by a narrow rectangular slot and rotated 45/spl deg/ with respect to the sides of the DRA to generate circular polarization. A parametric study of the length to width ratio to optimize the axial ratio bandwidth is given. A 3 dB axial ratio bandwidth of 10.6% is achieved when the length to width ratio is 1.9.
161 citations
TL;DR: In this article, a broadband, low profile dielectric resonator antenna with a stepped microstrip feed is presented. But the antenna size is not reduced by using metallic strips or patches.
Abstract: This paper presents a novel broadband, low-profile dielectric resonator antenna using relatively low dielectric constant substrate material. The rectangular DRA is fed with a stepped microstrip feed to ensure efficient coupling. Bandwidths in excess of 17% are obtained. In addition, the paper investigates methods to miniaturize the antenna using metallic strips or patches. Substantial size reduction is demonstrated while maintaining a reasonable bandwidth. Simulations as well as experimental results are presented.
145 citations
Patent•
08 Nov 2006
TL;DR: In this paper, a broadband antenna structure for a transponder of a radio frequency identification system consisting of a loop resonator with a feedpoint for connecting with an electronic circuit was proposed.
Abstract: A broadband antenna structure (10) for a transponder of a radio frequency identification system comprises - a loop resonator (12) with a feedpoint (14) for connecting with an electronic circuit (16), and - a dipole resonator (18) electrically connected to the loop resonator (12) and comprising two electrically isolated legs (20, 22).
129 citations
Patent•
01 Jun 2006TL;DR: In this article, a contour mode micromechanical piezoelectric resonator with a planar surface with a cantilevered periphery has been proposed, where the fundamental frequency for the displacement of the resonator is set in part lithographically by the planar dimension of the bottom electrode, the top electrode, or the layer.
Abstract: A contour mode micromechanical piezoelectric resonator. The resonator has a bottom electrode; a top electrode; and a piezoelectric layer disposed between the bottom electrode and the top electrode. The piezoelectric resonator has a planar surface with a cantilevered periphery, dimensioned to undergo in-plane lateral displacement at the periphery. The resonator also includes means for applying an alternating electric field across the thickness of the piezoelectric resonator. The electric field is configured to cause the resonator to have a contour mode in-plane lateral displacement that is substantially in the plane of the planar surface of the resonator, wherein the fundamental frequency for the displacement of the piezoelectric resonator is set in part lithographically by the planar dimension of the bottom electrode, the top electrode or the piezoelectric layer.
128 citations
TL;DR: In this article, a quasi-static analysis of the resonant properties of a sub-wavelength negative permittivity sphere was performed and it was shown that such a resonator will have a Q-factor that is only 1.5 times the Chu limit, matching the performance of other known electrically small spherical antenna designs such as the folded spherical helix and the spherical capped dipole.
Abstract: We show how resonators composed of negative permittivity materials can form the basis of effective small antenna elements. A quasi-static analysis of the resonant properties of a sub-wavelength negative permittivity sphere predicts that such a resonator will have a Q-factor that is only 1.5 times the Chu limit, matching the performance of other known electrically small spherical antenna designs, such as the folded spherical helix and the spherical capped dipole. Finite element simulation is used to demonstrate an impedance-matched radiating structure formed by coupling the resonator (a half-sphere above a ground plane) to a 50 ohm coaxial transmission line, where the coupling is mediated by a small conducting stub extending partially into the half-sphere. The resulting antenna has a ka<0.5, and its bandwidth and efficiency performance corresponds well to that predicted by the quasi-static analysis of the resonator.
127 citations
TL;DR: In this paper, the authors examined the multiple resonance phenomenon responsible for the ultra wideband response of the hybrid monopole-dielectric resonator antenna (DRA) and developed guidelines for designing the antennas for any specified frequency band.
Abstract: This letter examines in detail multiple resonance phenomenon responsible for the ultra wideband response of the hybrid monopole-dielectric resonator antenna (DRA). The physical insight gained by this investigation has lead to improved guidelines for designing the antennas for any specified frequency band. These simple guidelines are then verified using both simulated and measured data
119 citations
TL;DR: In this paper, a new four-element cylindrical dielectric resonator array is proposed as a wideband low profile monopole-like antenna, which employs the dominant HEM11delta mode in each CDR.
Abstract: A new four-element cylindrical dielectric resonator (CDR) array is proposed as a wideband low profile monopole-like antenna. Unlike previous investigations, the present antenna is easy to design and excite as it employs the dominant HEM11delta mode in each CDR. Ansoft's HFSS based design data and experimental results are presented. As much as 29% matching bandwidth (S11<-10 dB) with monopole-like radiation pattern over the entire band has been achieved with 4 dBi peak gain from a prototype occupying a very compact space measuring 0.6lambda0 by 0.1 lambda0 approximately
115 citations
Patent•
17 Jan 2006
TL;DR: In this paper, an antenna radiation collimator structure is provided as including a number of resonator circuit boards oriented to form a block structure, where a sheet of dielectric material is disposed between each of the number of circuit boards to maintain a substantially uniform spacing between each resonator board.
Abstract: An antenna radiation collimator structure is provided as including a number of resonator circuit boards oriented to form a block structure. A sheet of dielectric material is disposed between each of the number of resonator circuit boards to maintain a substantially uniform spacing between each of the resonator circuit boards. A plurality of conductive unit resonator cells may be disposed on first planar surfaces of each of the number of resonator circuit boards and a plurality of conductive strip lines may also be disposed on second planar surfaces of each of the number of resonator circuit boards. In this arrangement, radiation applied to a substantially central location of the block structure interacts with the plurality of conductive unit resonator cells and the plurality of conductive strip lines for redirecting the radiation out of front and rear facing surfaces of the block structure as respective first and second substantially collimated beams.
TL;DR: In this article, various multisegment cylindrical dielectric resonator antenna geometries were considered including stacked, core-plugged, and embedded stacked, and the results showed impedance bandwidths up to 68.1% compared to 21.0% for a homogeneous DRA with the same size and resonant frequency.
Abstract: Various multisegment cylindrical dielectric resonator antenna geometries are considered including stacked, core-plugged, and embedded stacked. Results show impedance bandwidths up to 68.1% compared to 21.0% for a homogeneous DRA with the same size and resonant frequency.
TL;DR: In this paper, the analysis of a two-segment rectangular dielectric resonator antenna (DRA) for broadening of the impedance bandwidth was discussed, and an appropriate structure was obtained that illustrates more than 76.8% impedance bandwidth (for S11>10 dB) at 3.32-7.46 GHz frequency band.
Abstract: This paper discusses the analysis of a novel two-segment rectangular dielectric resonator antenna (DRA) for broadening of the impedance bandwidth. In the proposed configuration, two rectangular dielectric sections are used which are separated by a metal plate. With this configuration, it is possible to excite two adjacent resonant frequencies. Utilizing the two-segment thin DRA and skillfully varying its aspect ratio, an appropriate structure is obtained that illustrates more than 76.8% impedance bandwidth (for S11>10 dB) at 3.32- 7.46 GHz frequency band.
TL;DR: In this article, a half-hemispherical dielectric resonator antenna (h-HDRA) is proposed and a two-element h-HDRA configuration is employed to design a broadband monopole-type radiator.
Abstract: A new half-hemispherical dielectric resonator antenna (h-HDRA) is proposed and a two-element h-HDRA configuration is employed to design a broadband monopole-type radiator. Two half sections of a hemispherical DRA are employed to enhance the impedance bandwidth by introducing an additional resonant mode. Since the new geometry of an h-HDRA is studied here for the first time, it is characterized using simulation and experimental studies. Two closely spaced resonant modes, which in a two-element h-HDRA generate monopole-type radiation are investigated. Results for both the single and two-element h-HDRAs are presented. As much as 35% impedance bandwidth (S11<-10dB) with more than 5 dBi peak gain, 99.08% efficiency and monopole-type radiation pattern has been demonstrated using a prototype occupying a compact volume measuring 0.48lambda0 by 0.2lambda0 approximately, lambda0 being the wave length corresponding to the center of the impedance bandwidth
TL;DR: In this article, a new class of reconfigurable antenna based on monopole structures containing liquid dielectrics is presented, and it is determined that the operating principle of this class of antenna is essentially that of a dielectric resonator, where salt (in solution) modifies the Dielectric properties.
Abstract: A new class of reconfigurable antenna based on monopole structures containing liquid dielectrics is presented. It was determined that the operating principle of this class of antenna is essentially that of a dielectric resonator, where salt (in solution) modifies the dielectric properties. The resonator column height determined the operating frequency, allowing match and frequency of operation to be fully tunable over 1–2.5 GHz while salinity mainly influences the bandwidth.
TL;DR: In this paper, a novel wideband hybrid dielectric resonator antenna structure consisting of a rectangular D resonator (DR) and a coplanar waveguide (CPW) inductive slot is proposed.
Abstract: A novel wideband hybrid dielectric resonator antenna structure comprises a rectangular dielectric resonator (DR) and a coplanar waveguide (CPW) inductive slot is proposed. In this configuration, the CPW inductive slot simultaneously acts as an effective radiator and the feeding structure of the DR. Dual resonances of the two radiators are merged to extend the antenna's bandwidth. A parametric study is performed to optimize the antenna performance and a prototype for 5-GHz WLAN application has been built and tested.
TL;DR: In this article, a cross-slot-coupled cylindrical dielectric resonator antenna (DRA) is studied theoretically and experimentally, where the center of the two slots at different positions of the DRA is enhanced by setting the centers of two slots in different positions and taking into consideration the partial independence of the slot modes.
Abstract: A cross-slot-coupled cylindrical dielectric resonator antenna (DRA) is studied theoretically and experimentally. In previous papers, a cross-slot of unequal slot lengths was centered under the dielectric resonator (DR), resulting in circular polarized operation of the antenna. In the present study, the design is enhanced by setting the centers of the two slots at different positions and taking into consideration the partial independence of the slot modes from the DRA mode. Thus, circular polarization (CP) bandwidth of up to 4.7% is attained experimentally in the broadside direction. It is also shown that a largely asymmetrical structure results in a very high bandwidth, but with the tradeoff of distorted CP operation off-broadside
TL;DR: In this paper, an investigation on increasing the bandwidth of dielectric resonator antennas by changing the radius to height and length to height ratios for cylindrical and rectangular geometries, respectively, was conducted.
Abstract: An investigation is conducted on increasing the bandwidth of dielectric resonator antennas by changing the radius-to-height and length-to-height ratios for cylindrical and rectangular geometries, respectively. A bandwidth of 30% is experimentally verified
Patent•
15 Aug 2006TL;DR: In this article, an antenna comprising a first dielectric resonator antenna operating within a first frequency band, a second Dielectric Resonator antenna operative within a second frequency band and a feeding structure electrically coupled to the first and second dielectoric resonator antennas was provided.
Abstract: Provided is an antenna comprising a first dielectric resonator antenna operative within a first frequency band, a second dielectric resonator antenna operative within a second frequency band, and a feeding structure electrically coupled to the first and second dielectric resonator antennas to receive and transmit signals at the first and second frequency bands through the first and second dielectric resonator antennas.
TL;DR: In this article, a high-Q racetrack resonator was developed based on a single-mode rib waveguide with a high Q factor of 38 000 with spectral sidelobes of 11 dB down and can be thermooptically scanned over its full free-spectral range.
Abstract: A wavelength selective optical switch is developed based on a high-Q racetrack resonator making use of the large thermooptic coefficient of silicon. The racetrack resonator was fabricated using a silicon-on-insulator (SOI) single-mode rib waveguide. The resonator shows a high Q factor of 38 000 with spectral sidelobes of 11 dB down and can be thermooptically scanned over its full free-spectral range applying only 57 mW of electrical power. A low power of 17 mW is enough to tune the device from resonance to off-resonance state. The device functions as a wavelength selective optical switch with a 3-dB cutoff frequency of 210 kHz.
TL;DR: In this article, a compact T-shaped dielectric resonator antenna with two equilateral-triangle cross sections is investigated, where the antenna is vertically placed on a finite ground plane and excited by a coaxial probe to provide broadband and conical radiation patterns.
Abstract: A compact T-shaped dielectric resonator antenna (DRA) with two equilateral-triangle cross sections is investigated in this letter. The DRA is vertically placed on a finite ground plane and excited by a coaxial probe to provide broadband and conical radiation patterns. In order to examine the proposed design, simulations and measurements were employed to investigate the proposed antenna, and a good agreement between them was obtained. The proposed design produces an impedance bandwidth of more than 60% from 1.6 to 3.1GHz, which effectively covers several promising application bands in contemporary wireless communication systems, such as digital communication systems (DCS: 1710-1880MHz), personal communication systems (PCS: 1850-1990MHz), universal mobile telecommunication systems (UMTS: 1920-2170MHz), wireless local area networks (WLANs: 2.4-2.485GHz). Additionally, stable conical patterns were also obtained within the interest frequency band
TL;DR: In this paper, a perforated dielectric resonator antenna (PDRA) is presented, which is equivalent of having an annular ring with lower permittivity outside the cylindrical disk, resulting in enhanced impedance bandwidth.
Abstract: A wideband perforated dielectric resonator antenna (PDRA) is presented. The effective permittivity of the dielectric resonator is altered by drilling holes into a circular ring lattice inside the DRA. The PDRA is equivalent of having an annular ring with lower permittivity outside the cylindrical disk, resulting in enhanced impedance bandwidth. The measured bandwidth of a prototype PDRA with relative permittivity 10.2 is 26.7% (S11<−10 dB).
TL;DR: In this article, a new shaped circularly polarised dielectric resonator antenna is proposed, which is easier to implement, free from a complicated feed network and offers wider axial ratio bandwidth.
Abstract: A new shaped circularly polarised dielectric resonator antenna is proposed. This antenna, compared to some previous investigations, is easier to implement, free from a complicated feed network and offers wider axial ratio bandwidth. About 4% AR bandwidth (< 3 dB) with S 11 < -10 dB and 3.5 dBi peak gain is reported.
Patent•
28 Sep 2006
TL;DR: In this paper, a thin-film bulk acoustic wave (BAW) resonator was proposed for use in RF selectivity filters operating at frequencies of the order of 1 GHz, where the insertion loss to the resonator is reduced by providing a dielectric material (18 ) in the same layer as the first electrode and surrounding that electrode.
Abstract: A thin-film bulk acoustic wave (BAW) resonator, such as SBAR or FBAR, for use in RF selectivity filters operating at frequencies of the order of 1 GHz. The BAW resonator comprises a piezoelectric layer ( 14 ) having first and second surfaces on opposing sides, a first electrode ( 16 ) extending over the first surface, and a second electrode ( 12 ) extending over the second surface, the extent of the area of overlap (R 1 ) of the first and second electrodes determining the region of excitation of the fundamental thickness extensional (TE) mode of the resonator. The insertion loss to the resonator is reduced by providing a dielectric material ( 18 ) in the same layer as the first electrode ( 16 ) and surrounding that electrode. The material constituting the dielectric material ( 18 ) has a different mass, typically between 5% and 15 %, from the material comprising the first electrode ( 16 ) it surrounds. The mass of the dielectric material ( 18 ) can be lower or higher than the mass of the first electrode ( 16 ). Planarisation of the dielectric material ( 18 ) enhances the performance of the device.
TL;DR: In this article, a transmission line method is proposed to compute the far-field radiation patterns of arbitrarily directed Hertzian dipoles that are embedded in a multilayer dielectric structure.
Abstract: A transmission line method is proposed to compute the far-field radiation patterns of arbitrarily directed Hertzian dipoles that are embedded in a multilayer dielectric structure. The evaluation of the field in the far-zone region is transformed into the evaluation of the field inside the multilayer structure by applying the reciprocity theorem. The horizontal field component inside the structure is derived by analyzing a transmission line circuit, and the vertical component is obtained from the horizontal component by separating the forward and backward waves. This method is implemented and verified by IE3D for the case of a three-layer structure excited by either electric Hertzian dipoles, magnetic Hertzian dipoles, or their combination. The radiation patterns of any antenna embedded in a multilayer dielectric structure can be computed with this method after replacing the physical antenna with a set of Hertzian dipoles. As examples, a quarter wavelength thin wire monopole antenna and a dielectric resonator antenna, both embedded in a multilayer structure, are investigated. Furthermore, the arrangement of the structure is optimized to maximize the antenna directivity. The results are also verified by the simulation of the entire structure with IE3D
Patent•
24 May 2006
TL;DR: In this paper, an electronic entity consisting of an electronic circuit and an antenna one part of which at least forms a conductive circuit connected to two ends of the electronic circuit is described.
Abstract: The invention concerns an electronic entity comprising an electronic circuit and an antenna one part of which at least forms a conductive circuit connected to two ends of the electronic circuit. The projection of the circuit formed by the antenna and the electronic circuit in a plane which is substantially parallel thereto, forms an intersection-free line and the antenna includes a winding which extends over strictly more than one turn.
TL;DR: In this article, the theoretical models of the ring resonator structure are adapted for calculating the relative permittivity of low-loss and high-loss printed wiring board materials at frequency range from 250 MHz to 10.0 GHz.
Abstract: Ring resonator structures are widely used to characterize the frequency and temperature dependence of the relative permittivity and loss tangent of printed wiring board materials. Several theoretical models for the ring resonator structures have been presented since the first ring resonator application. In this paper, the theoretical models of the ring resonator structure are adapted for calculating the relative permittivity of low-loss and high-loss printed wiring board materials at frequency range from 250 MHz to 10.0 GHz. In addition, a review of the characterization of the loss tangent using the ring resonator is presented. The review also provides information about differences of the results due to different approximation used for conductor losses of the microstrip line. The research presented in this paper is based on an experimental research with several different microstrip and strip line ring resonator structures. The results of this study provide useful information about applying the ring resonator method for measuring the relative permittivity and loss tangent of dielectric substrates
TL;DR: In this article, a rigorous analysis of the conformal-strip-excited hemispherical dielectric resonator antenna (DRA) with multiple parasitic strips is presented, where the problem is formulated using the Green's function approach, with the strip currents solved by using the method of moments.
Abstract: A rigorous analysis of the conformal-strip-excited hemispherical dielectric resonator antenna (DRA) with multiple parasitic strips is presented in this paper. The problem is formulated using the Green's function approach, with the strip currents solved by using the method of moments. It is found that the strips can be used to tune the operating frequency of both the linearly polarized (LP) and circularly polarized (CP) DRAs. In designing the LP DRA, the parasitic strips are placed symmetrically in pairs to minimize cross-polarized radiation fields. For the CP DRA, however, the parasitic strips are asymmetric, with their parameters determined by using the Genetic Algorithm. Measurements were carried out to verify the calculations, and reasonable agreement between theory and experiment is obtained.
TL;DR: In this paper, the dual functions of the rectangular hollow dielectric resonator antenna (DRA) as an antenna and a packaging cover are investigated, and the return loss, impedance and radiation patterns for the fundamental mode are presented at 2.4 GHz, a popular frequency band for the WLAN and wireless communications.
Abstract: The dual functions of the rectangular hollow dielectric resonator antenna (DRA) as an antenna and a packaging cover are investigated. The design methodology is discussed, and the return loss, impedance, and radiation patterns for the fundamental mode are presented at 2.4 GHz, a popular frequency band for the WLAN and wireless communications. A low-noise amplifier is integrated successfully into the embedded cavity to form an active DRA, and the amplified radiation patterns are analyzed. The proposed DRA provides a possible solution to the size minimization of transceivers.
TL;DR: In this article, a circularly polarised one-dimensional electromagnetic bandgap resonator antenna is demonstrated, which is generated by a sequentially rotated array of linearly polarised stripline slot antennas located in the ground plane of the device.
Abstract: A circularly polarised one-dimensional electromagnetic bandgap resonator antenna is demonstrated. Circular polarisation is generated by a sequentially rotated array of linearly polarised stripline slot antennas located in the ground plane of the device. The resonator antenna has the advantages of high gain, simple design and construction, very low sidelobes, good radiation pattern symmetry, and fairly constant boresight axial ratio across the operating bandwidth. Measured and computed results confirm the performance of the antenna.