Yagi-Uda Antenna Research Articles

High Gain Tri Band Yagi Uda Antenna with Proper Impedance Matching

High Gain Tri Band Yagi Uda Antenna with Proper Impedance Matching

Mutual coupling compensation for a practical VHF/UHF Yagi‐Uda antenna array

The performance of an antenna array is considerably affected by mutual coupling effects between antenna elements. When a large number of antenna elements are located close to each other, mutual coupling becomes more significant. In this study, by using a new mutual impedance matrix, a decoupling methodology for compensating mutual coupling effects in a practical very high frequency (VHF)/ultra high frequency (UHF) Yagi-Uda antenna array is introduced. No previous publications have studied VHF/UHF Yagi-Uda antenna arrays in this context. In the proposed scheme, extreme care has been taken to account for both self- and mutual impedance related to mutual coupling effects. Experimental and simulation results show that using the proposed method, a perfect decoupling is achieved. The application of high-resolution direction of arrival (DOA) estimation algorithms in decoupled experimental data leads to excellent performance of DOA estimation, in terms of accuracy and resolution. In addition, it is concluded (from experimental and simulation results) that mutual coupling effects between array elements as well as the root-mean-square error of estimated parameters depend on the direction of arrival. It is also deduced that in the presence of mutual coupling, estimation of signal parameter via rotation invariance techniques algorithm performs better than other subspace-based algorithms.

A 67-mW 10.7-Gb/s 60-GHz OOK CMOS Transceiver for Short-Range Wireless Communications

A low-power and high data-rate fully integrated 60-GHz on-off keying (OOK) transceiver for short-range wireless communication is demonstrated. The transceiver consists of a switch, transmitter, and receiver and uses OOK modulation for a compact and low-power design. With a highly efficient Tx, high-speed modulator/demodulator, and wideband characteristic, the transceiver has low-power and high data-rate capability. Implemented in 90-nm CMOS technology, the transmitter and the receiver consume 31 and 36 mW at 10.7 Gb/s and occupy an active footprint of 0.15 and 0.29 mm2, respectively. The transceiver with an on-board Yagi-Uda antenna achieves 10.7-Gb/s wireless OOK data transmission over 10 cm at a bit-error rate of less than 10-12 for 27 -1 pseudorandom binary sequence. As a result, the proposed transceiver achieves energy efficiency of 6.26 pJ/bit.

Design and Analysis of Tripple Band Koch Fractal Yagi Uda Antenna

The proposed antenna is Koch fractal printed Yagi-Uda antenna fed by SMA connector. The radiation characteristics of the antenna are simulated by CST Microwave Studio and analysed with the help of simulated results. The antenna's currents distribution becomes more uniform after being fractal, which is conducive to increase the antenna’s radiation directivity. The proposed Koch fractal Yagi-Uda antenna resonance at frequency of 7.81 GHz, 8.54 GHz and 9.42 GHz with gain of 9.67 dB, 10.4 dB and 10.61dB respectively. Parameter of antenna such as return loss, input impedance, smith chart, radiation pattern is analyzed for performance evaluation of Koch fractal Yagi-Uda antenna. DOI: http://dx.doi.org/10.11591/ijece.v3i4.2572

Rapid analysis and optimization of planar Yagi-Uda dipole arrays printed on a dielectric substrate

Planar antenna modeling requires a constrained solution space and open boundaries and so is highly computationally intensive. One of the methods used to overcome this is by using method of moments simulation. The method of moments is a highly efficient method of solving wire antenna structures and is commonly used in antenna optimization. A method of transforming a wire antenna structure to a planar antenna structure is presented using a 4-element Yagi-Uda antenna designed to resonate at 905 MHz. The wire to planar transformation is based on the circular cross section wire to planar strip, a spacing adjustment based on interelement capacitance, and a length scaling to compensate for the change in effective permittivity. The planar antenna shows slightly improved impedance performance at the resonance [voltage standing wave ratio VSWR=1.39]. This transformation decreased the antenna footprint by 15.11% after conversion for a wire antenna to a planar antenna in air with similar radiation characteristics and on FR4 1.6 mm thickness, the footprint increased by 52%. The antenna simulation time was reduced from 15 min using finite element method to less than 10 s for one cycle by using the method of moments solver. All antenna properties are essentially unchanged. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:184-190, 2014.

Diversity and directivity mode-switchable planar antenna by stacking and unfolding four antenna elements

A novel diversity and directivity mode-switchable planar antenna is presented. The antenna structure consists of four circular antenna elements. In the diversity mode, the four elements are unfolded on a plane for polarization diversity. Because of the orthogonal arrangement of the four elements, good diversity performance can be achieved. The antenna function is changed to directivity mode when the four elements are folded and stacked. Each element works as a reflector, a driver, and a director, as seen in the Yagi-Uda antenna principle, indicating that the antenna represents high directivity. A bent feed line and two methods of feeding are used to improve the directivity, for which a 4.5-dB greater peak gain is achieved than with the diversity mode. At 2.4 GHz, the antenna simulation results are consistent with the measurement results, and the performance is successfully proven.

IRBBO for Gain Maximization of Fifteen-Element Yagi-Uda Antenna

Biogeography is the study of distribution of biological species, over space and time, among random habitats. Recently introduced Biogeography Based Optimization (BBO) is a technique, where solutions of the problem are termed as habitats. Feature, i.e., Suitability Index Variable (SIV), sharing among various habitats is made to occur with migration operator where as exploration of new SIVs is done with mutation operator. Yagi-Uda antenna is a widely used antenna design due to various useful properties of high gain, low cost and ease of construction. Immigration Refusal BBO (IRBBO) is a BBO variant introduced with the objective of improved performance and faster convergence. Designing a Yagi-Uda antenna involves determination of element lengths and spacings between them to get desired radiation characteristics. The gain of Yagi-Uda antenna is difficult to optimize as there is no analytical formula to determine gain directly, it makes relationship between antenna parameters and its characteristics highly complex and non-linear. In this paper, fifteen-element Yagi-Uda antenna is optimized for maximum gain using IRBBO. The obtained results are compared with Standard BBO, Bi-Swarm optimization, Ellipsoid Algorithm and Genetic Algorithm (GA). IRBBO shows better results among other compared optimization techniques for Yagi-Uda antenna design problem.

Biogeography based Optimization for Gain Maximization of Nine-Element Yagi-Uda Antenna

Biogeography-Based Optimization (BBO) is a recently introduced population based algorithms which has shown impressive performance over other Evolutionary Algorithms (EAs). BBO is based on the study of distribution of biological organisms over space and time. BBO is a stochastic optimization technique, here, solutions for problem are considered as habitats whereas feature sharing, i.e. Suitability Index Variables (SIVs), among the habitats is known as migration and exploration of new SIV is accomplished as mutation. Yagi-Uda antenna design is most widely used antenna at VHF and UHF frequencies due to high gain, directivity and ease of construction. However, designing a Yagi-Uda antenna, that involves determination of optimal wire-lengths and their spacings, is a highly complex and non-linear engineering problem. In this paper, BBO algorithm is applied to optimize the lengths and spacings of nine-element Yagi-Uda antenna for maximum gain. The results obtained with this optimization technique are compared and the best results are tabulated in the ending sections of the paper.

Migration Effects on BBO Evolution in Optimizing Fifteen Element Yagi-Uda Antenna Design

Biogeography Based Optimization (BBO) is a recently introduced optimization technique based on science of biogeography, i.e., study of distribution of biological species over space and time. In BBO, potential solutions of a problem are grouped in integer vectors known as habitats. Feature, i.e., Suitability Index Variable (SIV), sharing among various habitats is made to occur with migration operator where as exploration of new SIVs is done with mutation operator. Different migration variants are proposed to increase the diversity in the population, with objective of improved performance of BBO algorithm. Yagi-Uda antenna is a widely used antenna design due to various useful properties of high gain, low cost and ease of construction. Designing a Yagi-Uda antenna involves determination of element lengths and spacings between them to get desired radiation characteristics. In this paper, various migration variants of BBO algorithm, reported till date, are investigated to optimize the lengths and spacings for Yagi-Uda antenna elements for maximum gain. The results obtained with these migration variants are compared and the best results are presented in the ending sections of the paper.

Accurate Effective Permittivity Calculation of Printed Center-Fed Dipoles and Its Application to Quasi Yagi-Uda Antennas

A closed-form method that accurately calculates the effective permittivity as seen by printed center-fed dipoles is presented. That accurate prediction enables the correct choice of the required dimensions of the dipole for a certain resonant frequency. For quasi Yagi-Uda antennas that usually have the driven element as a center-fed dipole, this means an accurate prediction of the required length of the driver, and subsequently all the other dimensions of the antenna without the need for extensive simulations and optimizations. The results obtained by full-wave electromagnetic simulations and measurements, over a wide range of design parameters, prove the validity of the derived method, which is based on the conformal mapping. The proposed method gives the correct estimation of the lengths of the dipoles with less than 10% error compared with the optimized design values. The conventional method results in estimations with as much as a 50% error.

접고 펼침에 따라 다이버시티와 지향성 모드로 변환이 가능한 평면형 안테나 어레이

본 논문은 다이버시티 모드와 지향성 모드를 스위치 할 수 있는 평면형 안테나 구조를 제안하였다. 제안된 구조는 네 개의 안테나 요소들을 한 평면에 배열했을 경우, 높은 격리도를 가지며 다이버시티 모드로 동작한다. 한편, 네 개의 안테나 요소들을 수직으로 적층 배치한 구조는 지향성 모드로 동작한다. 이 경우, 네 개의 안테나 요소들은 적층형 Yagi-Uda 안테나 구조를 따르며, 높은 이득을 갖도록 최적화되었다. 특히, 네 개의 안테나 요소에 두 가지의 급전 방법과 구부러진 급전선을 사용하여 성능을 극대화 시켰다. 2.4 GHz에서 동작하는 제안된 안테나는 시뮬레이션 결과와 실험적인 결과가 일치하는 것을 확인하였으며, 각 모드에서의 성능 또한 입증하였다. In this paper, a novel diversity and directivity mode-switchable planar antenna array is proposed. For the diversity mode, four elements are unfolded on the plane and high isolation can be achieved. On the other hand, the antenna function is changed to the directivity mode when they are folded and stacked. Each element works such as a stacked Yagi-Uda antenna with high directivity. Especially, the curved feed line as well as the hybrid feeding method is used to improve performances. The simulation results agree well with measurement results and it is successfully demonstrated that two modes are properly working at 2.4 GHz.

A New Broadband Quasi Yagi–Uda Antenna With an EBG-Truncated Ground Plane

The design of a new broadband quasi Yagi-Uda antenna is presented. The antenna is composed of an electromagnetic band-gap (EBG)-truncated ground plane and a feeding network formed by a Marchand balun and a coupling network. The quasi Yagi-antenna was designed to work at a central frequency of 3.5 GHz using a 30-mil FR4 substrate. The simulated and measured results show a relative bandwidth better than 53%, a cross polarization lower than -19 dB in the main lobe, and a front-to-back ratio better than 12 dB in the entire bandwidth.

Systematic Design of Parasitic Element Antennas—Application to a WLAN Yagi Design

In this letter, we present a synthesis method to design parasitic element antennas in a short and illustrative way without the need of parametric studies. The major aim of this method is to synthesize the antenna radiation pattern in a given direction, i.e., to find the equivalent reactive loads that must satisfy each parasitic element. The chosen structure to validate this principle is a 2.45-GHz Yagi-Uda antenna with surface mounted devices (SMD) acting as the synthesized reactive loads. This antenna has been successfully designed and measured. The SMD components have been introduced to demonstrate that the method is helpful to produce generic design.

A CIRCULARLY POLARIZED COMPACT ANTENNA FOR UHF BAND RFID READER

This paper presents a circularly polarized compact antenna based on the concept of Yagi-Uda antenna. By properly arranging three ring resonators operating at the fundamental mode, a compact Yagi-Uda like antenna is proposed to form directional pattern. This proposed antenna has comparable size with the ring resonator of quarter-wavelength, while the performances are comparable with the conventional microstrip antenna of half-wavelength. To validate the proposed design methodology, an antenna working at UHF radio- frequency identiflcation (RFID) band is benchmarked. Both simulated and measured results are shown for comparison.

Small Director Array for Low-Profile Smart Antennas Achieving Higher Gain

A small director array (SDA) is an antenna gain enhancing section of the low-profile smart antenna which can be used as a fixed array or reconfigurable array using switched parasitic elements. Gain improvements up to +10 dBi are achieved in the SDA through a Yagi-Uda configuration using parasitic elements with a large diameter. The array height is reduced by 50% comparing with the standard Yagi-Uda antenna. The reconfigurable SDA used an electronically steerable switched parasitic arrangement so that the beam can be steered from 0° to 360° in the horizontal plane. The height of the reconfigurable SDA is 0.2 λ. The measurements proved that the reconfigurable SDA can increase the antenna gain by 3 dB. The front to back ratio showed significant improvement. The proposed SDA also had the advantages of low cost and low power consumption, thus promising for applications in small satellites, unmanned aerial vehicles and mobile terminals.

Design of Yagi-Uda Antenna in 900 MHz Band for Multi-Band Base Station Antenna

Design of Yagi-Uda Antenna in 900 MHz Band for Multi-Band Base Station Antenna

Frequency and pattern reconfigurable dipole-Yagi antenna

A novel dipole-Yagi antenna is presented with pattern and frequency reconfigurable capability. The novel structure is based from Yagi-Uda antenna, consist of dipole as a main radiator and four parasitic metal strips. The parasitic metal strips can be formed to function as part of the radiator, reflector, or director by means of switches. The switches are located at specific position. By bridging the main radiator to the metal strips, frequency reconfiguration can be achieved. Whilst by bridging the strips itself, will results in pattern changing. Three switchable patterns at 2.5 GHz and four switched band at 0.98, 1.5, 2.1, and 2.5 GHz are demonstrated. This antenna exhibits −10 dB return loss and 76–79% efficiency. Good agreement between measured and simulated results is observed. The antenna might be useful for wireless body area networks communication system. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:447–450, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27323

Yagi-Uda Antenna Design Optimization for Maximum Gain using different BBO Migration Variants

Biogeography is the study of distribution of biological species, over space and time, among random habitats. Recently developed Biogeography-Based Optimization (BBO) is a technique, where solutions of the problem under consideration are named as habitats; similar to chromosome in Genetic Algorithms (GAs) and particles in Particle Swarm Optimization (PSO). Feature sharing among various habitats, i.e., exploitation, is made to occur due to migration operator wheras exploration of new SIV values, similar to that of GAs, is accomplished with mutation operator. In this paper, various migration variants of BBO algorithm, reported till date, are investigated to optimize the lengths and spacings for YagiUda antenna elements for maximum gain. The results obtained with these migration variants are compared and the best results are presented in the ending sections of the paper.

Plasmonic Antennas Hybridized with Dielectric Waveguides

For the purpose of using plasmonics in an integrated scheme where single emitters can be probed efficiently, we experimentally and theoretically study the scattering properties of single nanorod gold antennas as well as antenna arrays placed on one-dimensional dielectric silicon nitride waveguides. Using real space and Fourier microscopy correlated with waveguide transmission measurements, we quantify the spectral properties, absolute strength, and directivity of scattering. The scattering processes can be well understood in the framework of the physics of dipolar objects placed on a planar layered environment with a waveguiding layer. We use the single plasmonic structures on top of the waveguide as dipolar building blocks for new types of antennas where the waveguide enhances the coupling between antenna elements. We report on waveguide hybridized Yagi-Uda antennas which show directionality in out-coupling of guided modes as well as directionality for in-coupling into the waveguide of localized excitations positioned at the feed element. These measurements together with simulations demonstrate that this system is ideal as a platform for plasmon quantum optics schemes as well as for fluorescence lab-on-chip applications.

Multi-objective Gain-Impedance Optimization of Yagi-Uda Antenna using NSBBO and NSPSO

Biogeography-Based Optimization (BBO) is a population based algorithm which has shown impressive performance over other Evolutionary Algorithms (EAs). BBO algorithm is based on the study of distribution of biological organisms over space and time. YagiUda antenna design is most widely used antenna at VHF and UHF frequencies due to high gain, directivity and ease of construction. However, designing a Yagi-Uda antenna, that involves determination of optimal wire-lengths and their spacings, is highly complex and non-linear engineering problem. It further complicates as multiple objectives, viz. gain, and impedance, etc., are required to be optimized due to their conflicting nature, i.e., reactive antenna impedance increases significantly as antenna gain is intended to increase. In this paper Non-dominated Sorting BBO (NSBBO) is proposed and where standard and blended variants of BBO are investigated in optimizing six-element Yagi-Uda antenna designs for multiple objectives, viz., gain and impedance, where ranking of potential solutions is done using non-dominated sorting. The simulation results of BBO variants and Particle Swarm Optimization (PSO) are presented in the ending sections of the paper that depict clearly that NSBBO with blended migration operator is best option among all.