Showing papers on "Feed line published in 2015"

Apparatus and methods for transmitting wireless signals

Abstract: Aspects of the subject disclosure may include, for example, an antenna structure having a feed point for coupling to a dielectric core of a cable that propagates electromagnetic waves without an electrical return path, and a dielectric antenna, substantially or entirely devoid of conductive external surfaces, coupled to the feed point, the dielectric antenna facilitating receipt, at the feed point, the electromagnetic waves for propagating the electromagnetic waves to an aperture of the dielectric antenna for radiating a wireless signal. Other embodiments are disclosed.

Low-Profile Log-Periodic Monopole Array

Abstract: This paper presents a low-profile log-periodic monopole array antenna with end-fire radiation and vertical polarization. It consists of 15 monopole elements and a conductor-backed coplanar strip line as the feeding line. The monopoles are of the same height but loaded with top hats of different sizes to achieve the required resonant frequencies. A wideband transition from coaxial line to conductor-backed coplanar strip line is designed for the antenna feed. A prototype is fabricated and tested. Measured results show that an impedance bandwidth from 1.5 to 6.8 GHz (4.53:1) for $\text{VSWR { and a gain better than 4.5 dBi over the same operating frequency band are obtained while the antenna has a very low profile of only $0.047\;\lambda_L$ ( ${{{\lambda}}_L}$ is the free-space wavelength at the lowest operating frequency).

Slotted ground microstrip antenna with FSS reflector for high-gain horizontal polarisation

Abstract: The design of a high-gain horizontally polarised antenna for ultra-wideband (UWB) operation is presented and experimentally demonstrated. Gain enhancement is achieved by using a frequency selective surface (FSS) reflector. Both the antenna and the FSS have simple structures and are printed on a similar substrate. The antenna is a three-stepped narrow rectangular slot excited using a three-stepped microstrip feed line. By optimising the lengths and widths of the sections of the slot and the feed line, an ultra-wide impedance bandwidth (3.2–12 GHz, measured) has been achieved. The FSS is a two-layer structure where each layer is an array of rectangular patches printed on one side of the substrate. With the application of the FSS, the antenna gain is enhanced by 3–4 dBi over most of the band. The polarisation purity (in terms of the measured cross-polar difference) is also improved with the FSS. Such an antenna–FSS combination will be useful for high-gain UWB applications requiring horizontal polarisation.

Compact Low-Profile Dual Band Metamaterial Antenna for Body Centric Communications

Abstract: A compact low profile dual band metamaterial antenna is presented for wireless body centric communications. It is composed of a zeroth-order loop loaded periodically with mu-negative transmission line (MNG-TL) for a lower frequency band and a circular patch located in the center of loop for an upper frequency band. The MNG-TL loop based on the fundamental infinite wavelength property allows current along the loop to remain the same magnitude and phase to create omnidirectional radiation pattern in azimuth plane at the lower band for on-body communications. On the other hand, a unidirectional radiation pattern is generated by a circular patch in direction normal to a human body at the upper frequency band for off-body communications simultaneously. In order to feed the MNG-TL conveniently, a transition based on a CPW transmission line is proposed. Finally, the proposed antenna is fabricated and measured. It is demonstrated that the measurement has good agreement with simulation.

Dynamic polarization and coupling control for a steerable, multilayered cylindrically fed holographic antenna

Abstract: An apparatus is disclosed herein for a cylindrically fed antenna and method for using the same. In one embodiment, the antenna comprises: an antenna feed to input a cylindrical feed wave; a first layer coupled to the antenna feed and into which the feed wave propagates outwardly and concentrically from the feed; a second layer coupled to the first layer to cause the feed wave to be reflected at edges of the antenna and propagate inwardly through the second layer from the edges of the antenna; and a radio-frequency (RF) array coupled to the second layer, wherein the feed wave interacts with the RF array to generate a beam.

Frequency Reconfigurable U-Slot Antenna for SDR Application

Abstract: In this paper, a novel frequency reconfigurable U-slot microstrip antenna with T-shaped feed line for Software Defined Radio applications is proposed. The proposed antenna, indexed as A-I in this paper, operates at three different frequencies: 1.85GHz, 1.9GHz and 2.4GHz depending on the switching states of PIN diodes. Furthermore, to strengthen the proposed design concept and strategy another improved antenna (A-II) is designed and tested. In comparison to antenna A-I, the improved antenna design (A-II) utilizes four slots/PIN diodes in order to increase the number of reconfigurable frequency states. Depending on the switch states of four PIN diodes, antenna A-II operates on five different reconfigurable frequency bands centered at: 1.5GHz, 1.6GHz, 1.8GHz, 1.9GHz and 2.24GHz. The measured results show a return loss better than 22 dB, maximum gain of 2.5 dB and maximum efficiency of 78%. Moreover, radiation pattern for the proposed antennas is stable at all operating frequencies.

A Compact Multiple Band-Notched Planer Antenna with Enhanced Bandwidth Using Parasitic Strip Lumped Capacitors and DGS-Technique

Abstract: UWB antenna with dual notched characteristics fed by microstrip transmission line is presented in this paper. The tapered connection between the rectangular patch and the feed line is used to produce a good impedance matching from 2.3 to 11.5 GHz. A dual band frequency notches are achieved using U-DGS loaded with lumped capacitors. The first notch frequency band is achieved using DGS to reduce the interference with WIMAX from 3.3 to 3.7 Ghz. The second notch frequency band is also achieved using U-parasitic strip placed in the ground plan to eliminate the interference with WLAN from 5.2 to 5.9 GHz. Lumped capacitors are combined with the slot due to miniaturize the slot size. The size of the resonator is reduced by more than 40% when lumped capacitors are used. The proposed antenna hasVSWR < 2 except the notched bands. The simulated results confirm that the antenna is suitable for UWB applications. DOI: http://dx.doi.org/10.11591/telkomnika.v13i2.6976

CPW‐fed broadband circularly polarized rectangular slot antenna with L‐shaped feed line and parasitic elements

Abstract: A new coplanner waveguide-fed broadband circularly polarized (CP) rectangular slot antenna is proposed. Circular polarization (CP) is obtained using L-shaped feed line protruded from the signal line and rectangle-shaped parasitic element (PE). The CP bandwidth can be significantly enhanced by placing a strip adjacent to the rectangle-shaped PE. By adjusting the length of the strip, the CP bandwidth is obtained as high as 48.28% (2.2–3.6 GHz) with axial ratio (AR) ≤ 3 dB. Impedance bandwidth of 63.97% (1.93–3.745 GHz) with VSWR ≤ 2 is achieved. The antenna has a small size of 60 × 50 mm2. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1788–1794, 2015

Detecting proximity using antenna feedback

Abstract: An electronic device provides a detuning monitor circuit configured to detect a change in a voltage standing wave ratio (VSWR) between a radio frequency (RF) transmitter and an RF antenna relative to a predetermined VSWR baseline and a proximity detector circuit configured to adjust transmission power of a carrier wave transmitted from the RF transmitter, if the change fails to satisfy an acceptable VSWR condition. Network proximity detectors are also provided to allow coordination of antenna subsystems to comply with specific absorption rate (SAR) constraints and/or maintain/improve antenna performance.

Balanced Bandpass Filter Using Stub-Loaded Ring Resonator and Loaded Coupled Feed-Line

Abstract: A balanced bandpass filter is proposed based on stub-loaded ring resonators (SLRRs) and loaded coupled feed-lines (CFLs) with high selectivity and common-mode (CM) rejection By controlling the coupling coefficient of the CFLs, three transmission poles within the differential passband are achieved The CFLs are loaded with open- and short-circuited stubs at the end of the traditional parallel-coupled feed-lines, which resulting in multiple transmission zeros (TZs) in differential mode (DM) and CM to improve the passband selectivity and CM suppression, simultaneously Finally, the proposed filter is designed and fabricated, the simulated and measured results are in good agreement The filter shows low insertion loss, multiple transmission zeros, high selectivity and enhanced CM rejection

Meandered CPW‐fed hexagonal split‐ring resonator monopole antenna for 5.8 GHz RF‐ID applications

Abstract: The design of a compact monopole antenna for 5.8 GHz RFID application is presented. Hexagonal split ring resonator is used as radiating element and is fed with meandered CPW feed line. Meandered CPW feed line is used to improve the impedance matching of the antenna. The antenna prototype is fabricated and tested. The proposed antenna is fabricated on FR4 substrate and occupies a small size of 13 × 19.8 × 0.8 mm3. The measured results of the proposed antenna show that the impedance bandwidth is from 5.4 to 6.0 GHz. Good omnidirectional pattern obtained in H-plane and bidirectional pattern obtained in E-plane. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:681–684, 2015

4G antenna with metal frame

Abstract: A 4G antenna with a metal frame comprises the metal frame, a PCB and an antenna part. The PCB comprises a clearance area and a metal area, the antenna part is located in the clearance area, and comprises a feed supply, a grounding point and a line part, the grounding point and the feed supply are arranged on the PCB, the grounding point is connected with the metal area, a feed line is led out of the feed supply, and the feed supply horizontally extends from the end, close to the metal frame, of the feed line to form a high-frequency line and a low-frequency line which are opposite in direction. First low-frequency resonance is generated by a first low-frequency branch, a second low-frequency branch and a second frame body. First high-frequency resonance is generated by the first low-frequency branch, the second low-frequency branch and a first frame body radiation loop. A first high-frequency branch and the second frame body are coupled to generate second high-frequency resonance. A parasitic branch is used for generating third high-frequency resonance. The method that the front part of the low-frequency line is bent in the reverse height direction is utilized, and the low-frequency bandwidth of the antenna is expanded. Each high-frequency resonance is generated by the radiation of the metal frame, and the problem that the metal frame shields high-frequency antenna radiation is solved.

Application of Defected Ground Structure to Suppress Out-of-Band Harmonics for WLAN Microstrip Antenna

Abstract: An application of defected ground structure (DGS) to reduce out-of-band harmonics has been presented. A compact, proximity feed fractal slotted microstrip antenna for wireless local area network (WLAN) applications has been designed. The proposed 3rd iteration reduces antenna size by as compared to rectangular conventional antenna and by introducing H shape DGS, the size of an antenna is further reduced by . The DGS introduces stop band characteristics and suppresses higher harmonics, which are out of the band generated by 1st, 2nd, and 3rd iterations. H shape DGS is etched below the 50 Ω feed line and transmission coefficient parameters are obtained by CST Microwave Studio software. The values of equivalent and model have been extracted using a trial version of the diplexer filter design software. The stop band characteristic of the equivalent model also has been simulated by the Advance Digital System software, which gives almost the same response as compared to the simulation of CST Microwave Studio V. 12. The proposed antenna operates from 2.4 GHz to 2.49 GHz, which covers WLAN band and has a gain of 4.46 dB at 2.45 GHz resonance frequency.

Liquid-metal frequency-reconfigurable slot antenna using air-bubble actuation

Abstract: Liquid metal actuated by pressure-driven air bubbles is guided within channels to dynamically reconfigure the length of the radiating aperture and feed line of a slot antenna. The gallium-based liquid metal is held in position by air bubbles, and liquid-metal motion is induced when a pressure differential is created. In contrast to conventional hydraulic or pneumatic actuation of gallium-based liquid metal, the pressure actuation described here is reversible and repeatable, as the liquid metal is enveloped by a thin layer of NaOH solution, which acts as a slip layer and reduces any metal oxidation. The slot antenna achieves a 26% tunable bandwidth with a contiguous range from 1.42 to 1.84 GHz for which the S 11 is <;-10 dB. The peak gain ranges from 4.8 dBi in its lowest-frequency state to 4.1 dBi in its highest-frequency state.

A compact triple band notch circular ring antenna for UWB applications

Abstract: In this article, a study of a triple band notched circular ring monopole ultrawide band (UWB) antenna is presented. The UWB antenna consists of a circular ring radiating patch and rectangular ground plane with two small slots near the feed line for bandwidth enhancement. The proposed antenna can reject worldwide interoperability for microwave access (WiMAX) band (3.3–3.8 GHz), wireless local area network (WLAN) band (5–6 GHz) and X-band downlink satellite communication band (7.1–7.9 GHz). The WiMAX and WLAN band rejections are realized by introducing two arc shaped elliptical slots and single elliptical split ring slot in the radiating patch, respectively. Furthermore, a pair of rectangular single split ring resonators is used to obtain the rejection of X-band downlink satellite communication signal. The proposed UWB antenna is fabricated and measured. The measured results are in good agreement with the simulated ones. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:668–672, 2015

A compact asymmetric slot dual band antenna fed by CPW for PCS and UWB applications

Abstract: A compact slot antenna with an overall dimension of 30 × 30 × 1.6 mm3 is proposed for dual band applications. The radiating element is a hexagonal shape patch which protrudes from a Co-Planar Waveguide (CPW) feed into a step shape slot. The slot is basically rectangular in shape and is extended by inserting rectangular cuts of different sizes on the ground plane around it. The ultrawide impedance bandwidth is achieved using asymmetric feed line along with extended rectangular cuts around the slot. For realizing the second band for personal communication system applications (near 1.9 GHz), a metallic stub of quarter wave length is attached at the top of the slot. The measured impedance bandwidth (for S11 < −10 dB) is 110 MHz (1.86–1.97 GHz) for the first band and 9 GHz (3.0–12.0 GHz) for the second band. The antenna is further characterized by omnidirectional radiation patterns in the H-plane, dumb-bell shape radiation patterns in the E-plane and a peak gain of 3–5 dBi over the ultrawideband. All the measured results are found to be in good agreement with the simulated results. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:243–254, 2015.

Low return loss slotted rectangular microstrip patch antenna at 2.4 GHz

Abstract: In this paper, the design of a slotted rectangular microstrip patch antenna is reported which is suitable for high data rate application. The antenna is fed by a microstrip line designed for a frequency of 2.4 GHz. The designed antenna has inset feed over microstrip line feeding geometry. The dimension of the feed line is 7.64×14.89 mm. The microstrip antenna is designed over a FR4 epoxy substrate with dielectric constant, e Γ =4.4. The antenna is designed using high frequency structural simulator (HFSS) software with return loss of almost −40dB and VSWR 1 at 2.4 GHz providing a bandwidth of around 160 MHz.

A planar UWB monopole antenna with dual band notched function

Abstract: A printed monopole antenna for UWB applications with dual band notch property is proposed in this letter. The UWB monopole consists of modified circular patch with an elliptical slot to reject WiMAX frequencies (3.3–3.8 GHz). The modified ground plane is introduced to attain the wide impedance UWB bandwidth with G-shaped slot below the feed line to reject 5.15–5.85 GHz WLAN frequencies. The length of embedded slot not only depends on notch frequency and substrate dielectric constant but also depends on substrate thickness and slot width. In this letter, we have presented a technique to calculate accurately the slot length of the embedded slot. The simulated and measured result shows that the designed antenna is expected to be good candidate for UWB applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:99–104, 2015

Multi-mode feed network for antenna array

Abstract: A dual-mode feed network for an antenna array or combination antenna is provided. Two transmission line structures propagate signals according to two different electromagnetic propagation modes, such as TE, TM, TEM and quasi TEM modes. The two transmission line structures are operatively coupled to different components of the antenna array. One transmission line structure may be a stripline or microstrip, and the other transmission line structure may be a waveguide such as a Substrate Integrated Waveguide. Both transmission line structures may branch to reach multiple elements of the antenna array. The transmission lines may share common features, for example by embedding the stripline within the waveguide.

Point-to-point radio link variation at E-band and its effect on antenna design

Abstract: Radio propagation will strongly influence the design of the antenna and front-end components of E-band point-to-point communication systems. Based on the ITU rain model, the rain attenuation is estimated in a statistical sense and it is concluded that for backhaul links of 1–10 km, antennas with a gain of 49.5 dBi are required. Moreover, depolarization can be a limiting factor for backhaul systems that are employing orthogonal polarization in order to improve capacity. Antenna mast movement becomes a relevant problem due to the narrow beamwidth of the high gain antennas, which is around 0.7◦ . We propose to implement a focal plane array as feed for the parabolic reflector antenna. This is to tackle the mast movement by electronic beam steering and to increase EIRP by increasing the number of active antenna elements, and to assist the mechanical alignment during installation.

Wideband Antenna with Reconfigurable Band Notched Using EBG Structure

Abstract: A wideband antenna with band notch function using electromagnetic bandgap (EBG) structure is proposed. The antenna is capable of reconfiguring up to three band notch operation. Three EBGs are aligned underneath the feed line of the wideband antenna. The transmission lines over EBGs unit cells perform as a band stop filter. A switch is placed on each of the EBG structure, which enables the reconfigurable band stop operation. The simulated and measured reflection coefficients, together with the radiation patterns, are shown to demonstrate the performance of the antenna.

A compact UWB antenna with dual 3.5/5.5 GHz band-notched characteristics

Abstract: In this article, a compact octagonal-shaped UWB antenna with Minkowski fractal-shaped notch and a dual C-shaped notch is presented. The Minkowski fractal helps to obtain band rejection at WiMAX (3.4–3.7 GHz) band, whereas dual C-shaped notch on either side of feed line provides the band rejection at WLAN (5.15–5.825 GHz) band. Moreover, a rectangular slot is also inserted in the ground plane, which helps to obtain the desired UWB bandwidth. The proposed antenna has the compact size of 26 × 16.5 mm2. The proposed antenna shows proper impedance matching, stable radiation pattern with good antenna gain (2–5 dBi) over the entire UWB frequency range. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:551–556, 2015

Transmission line and flat cable

Abstract: A stacked insulator (10), which is obtained by stacking a plurality of insulator layers, includes: a first ground conductor pattern (21), a second ground conductor pattern (22), and a first signal conductor pattern (31) which form a first transmission line unit (SL1); and a third ground conductor pattern (23), a fourth ground conductor pattern (24), and a second signal conductor pattern (32) which form a second transmission line unit (SL2). The first signal conductor pattern (31) is disposed extending along the second signal conductor pattern (32). The first ground conductor pattern (21) and the third ground conductor pattern (23) are formed in different insulator layers, and partially overlap each other in a planar view.

Frequency reconfigurable aperture-coupled microstrip patch antenna using Defected Ground Structure

Abstract: This paper designs and simulates frequency reconfigurable microstrip patch antenna using Defected Ground Structures (DGS) with aperture coupled feed line. Single element with two regular slots etched on the ground layer has been designed to represent two resonant frequency 7.5 GHz and 8.85 GHz. Comparison two antenna designs without and with DGS structure is reported in this paper. Simulated results shows that etched DGS structure on the ground plane can eliminate one of the resonant frequencies. Effect of DGS structure on the designed antenna based on switching mode at the feed line.

A new design formulae for feed line dimensions of the rectangular microstrip patch antenna by using equivalent design concept

Abstract: The designing of rectangular microstrip patch antenna requires classical formulae to calculate. For every new design same formulae are used which is time consuming and lengthy. The Bhatnagar's Postulate gives the idea of transforming one design into another by using normalized thickness H (ratio of height of substrate to guided wavelength) and scaling factor ψ (ratio of the square root of the dielectric constant of the first design to second). But it is limited to patch only. This paper uses the same principle for calculating new formulae for the feed line dimensions. The first antenna design dimensions are calculated by classical formulae and then others are simulated with the new formulae of feed line dimensions, Bhatnagar's Postulate for the patch and the calculations of the first design. This gives very good results.

Radial line slot array antenna with vertical waveguide feed for F-band communication

Abstract: The authors present concentrically arrayed radial line slot array antenna for operation at 106 GHz. For compact design, they propose a vertical waveguide feeding with a cross-slot structure at the waveguide to cavity transition. Aperture design and optimisation are carried out using particle swarm optimisation with the goal to minimise the cross-polarised radiation. Antenna prototypes were fabricated using a slotted plate with nickel and radial line cavity with copper. Fabricated aperture showed 72% peak radiation efficiency at 106.3 GHz with a gain bandwidth of 8.5% and 3-dB axial ratio bandwidth of 18%.

Tool turret for processing workpieces and processing system with this type of tool turret

Abstract: A tool turret for machining workpieces has a housing and with a part that can be rotated around an axis of rotation into several rotary positions. On the rotating part, several tool holders are mounted on the circumference for holding tools to which a cryogenic cooling medium can be fed by means of a first feed line and a respective second feed line. The first feed line can be moved in a linear manner in at least some sections by a linear actuator whereby the first feed line is connected in a first position with the second feed line belonging to the tool in work position and in a second position is disconnected from the second feed lines for changing the rotary position of the rotating part. The tool turret enables the cryogenic cooling medium to be fed to the tools in a simple and reliable manner.

Ultra Wideband PIFA Antenna with Supporting GSM and WiMAX for Mobile Phone Applications

Abstract: In this paper the PIFA antenna with multiband resonance for GSM 900, GSM 1800, WLAN 2400MHz, Bluetooth, WiMAX, 3G, 4G and UWB frequency from 3.1-10.6 GHz application is presented. Slots or stubs on the ground plane produce lower frequency resonance. Taper feed line method has been used to achieve Ultra Wide Band. The final antenna results are compared by FEM and TDM techniques using HFSS and CST microwave studio 2011 simulation softwares. The antenna is built on FR-4 low cost substrate with dielectric constant a#x03B5;r = 4.4 and loss tangent tan a#x03B4;=0.02. The substrate height is h=1.6 mm and the substrate dimensions are 120mm×60mm. Simulation results of Specific Absorption Rate (SAR) shows that antenna has 1.44 W/Kg and 2.65 W/Kg for GSM 900 and GSM 1800. The antenna has high gain between 2-6.5 dBi with Omni directional radiation pattern. The antenna results are compared with other pervious researches.

A deterministic channel model for multi-access broadband powerline communication

Abstract: This paper presents an alternative approach to model the transfer characteristics of power lines for broadband power line communications (PLC). The model is developed by considering the power line to be a two-wire transmission line and the theory of transverse electromagnetic (TEM) wave propagation applied. The characteristic impedance and attenuation constant of the power line are determined through measurements. These parameters are used in model simplification and determination of other model parameters for typical indoor multi-tapped transmission line system. The transfer function of the PLC channel is determined by considering the branching sections as parallel resonant circuits attached to the main line. The model is evaluated through comparison with measured transfer characteristics of known topologies and it is in good agreement with measurements.

UWB monopole antenna with multiple fractal slots for band-notch characteristic and integrated Bluetooth functionality

Abstract: This article presents the design of compact microstrip-fed modified half annular-shaped planar monopole antenna for ultra-wideband (UWB) (3.1–10.6 GHz) application. An electromagnetically coupled circular-shaped parasitic patch is introduced at the backside of the substrate to enhance the bandwidth of the whole antenna by shifting the lower frequency band. A rectangular slot-embedded ground plane at the bottom surface of the substrate improves the impedance bandwidth with excellent matching characteristics for the entire design frequency band. In addition to this, a half Minkowski fractal slot, a hybrid fractal slot, and Sierpinski arrowhead curve fractal slot are coupled to the feed line individually such that three UWB antennas with band-notched characteristic are realized that mitigate the interference between UWB and Wireless local area network (5.15–5.825 GHz) assigned to IEEE 802.11a and HIPERLAN/2 can be reduced. Now to increase the functionality of the antenna, a second iterated fractal binary tre...