Topic 6. Radiation Fundamentals
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Antenna Tuning for WCDMA RF Front End
Antenna tuning for WCDMA RF front end Reema Sidhwani School of Electrical Engineering Thesis submitted for examination for the degree of Master of Science in Technology. Espoo 20.11.2012 Thesis supervisor: Prof. Olav Tirkkonen Thesis instructor: MSc. Janne Peltonen Aalto University School of Electrical A’’ Engineering aalto university abstract of the school of electrical engineering master's thesis Author: Reema Sidhwani Title: Antenna tuning for WCDMA RF front end Date: 20.11.2012 Language: English Number of pages:6+64 Department of Radio Communications Professorship: Communication Theory Code: S-72 Supervisor: Prof. Olav Tirkkonen Instructor: MSc. Janne Peltonen Modern mobile handsets or so called Smart-phones are not just capable of commu- nicating over a wide range of radio frequencies and of supporting various wireless technologies. They also include a range of peripheral devices like camera, key- board, larger display, flashlight etc. The provision to support such a large feature set in a limited size, constraints the designers of RF front ends to make compro- mises in the design and placement of the antenna which deteriorates its perfor- mance. The surroundings of the antenna especially when it comes in contact with human body, adds to the degradation in its performance. The main reason for the degraded performance is the mismatch of impedance between the antenna and the radio transceiver which causes part of the transmitted power to be reflected back. The loss of power reduces the power amplifier efficiency and leads to shorter battery life. Moreover the reflected power increases the noise floor of the receiver and reduces its sensitivity. -
Multi Application Antenna for Wi-Fi, Wi-Max and Bluetooth for Better Radiation Efficiency
International Journal of Scientific Engineering and Applied Science (IJSEAS) - Volume-1, Issue-4, July 2015 ISSN: 2395-3470 ` www.ijseas.com Multi Application Antenna for Wi-Fi, Wi-max and Bluetooth for better radiation efficiency Hina D.Pal, J.Jenifer, Kavitha Balamurugan, M.E,Suntheravel, PG student, PG student, Associate Prof. Assistant Prof. KCG College of technology, KCG College of technology, KCG College of technology, KCG College of technology, Karapakkam, Karapakkam, Karapakkam, Karapakkam, Chennai-600097 Chennai-600097 Chennai-600097 Chennai-600097 ABSTRACT: Microstrip antenna is a printed type antenna This paper presents the radiation performance of rectangular consisting of a dielectric substrate sandwiched in patch antenna having a two slots. The design is used for between a ground plane and a patch. In this project three different frequencies 2.4, 5 and 7GHz . As a substrate Micro strip patch antenna technology is used for material Cu_clad is used. The simulated results for this different application for different frequencies antenna are obtained by varying the length and width of different materials are used for better efficiency. three dipoles.The results indicate that rectangular patch antenna with two slots offers a good antenna efficiency 41.576 at 2.45 GHz,51.958 at 5 GHz,46.810 at 7 GHz with the input feed 50 Ohm. Desired patch antenna design was simulated by ADS simulator program. ADS supports every step of the design process—schematic capture, layout, frequency-domain and time-domain circuit simulation, and electromagnetic field simulation, allowing the engineer to fully characterize and optimize an RF design without changing tools. -
Chapter 22 Fundamentalfundamental Propertiesproperties Ofof Antennasantennas
ChapterChapter 22 FundamentalFundamental PropertiesProperties ofof AntennasAntennas ECE 5318/6352 Antenna Engineering Dr. Stuart Long 1 .. IEEEIEEE StandardsStandards . Definition of Terms for Antennas . IEEE Standard 145-1983 . IEEE Transactions on Antennas and Propagation Vol. AP-31, No. 6, Part II, Nov. 1983 2 ..RadiationRadiation PatternPattern (or(or AntennaAntenna Pattern)Pattern) “The spatial distribution of a quantity which characterizes the electromagnetic field generated by an antenna.” 3 ..DistributionDistribution cancan bebe aa . Mathematical function . Graphical representation . Collection of experimental data points 4 ..QuantityQuantity plottedplotted cancan bebe aa . Power flux density W [W/m²] . Radiation intensity U [W/sr] . Field strength E [V/m] . Directivity D 5 . GraphGraph cancan bebe . Polar or rectangular 6 . GraphGraph cancan bebe . Amplitude field |E| or power |E|² patterns (in linear scale) (in dB) 7 ..GraphGraph cancan bebe . 2-dimensional or 3-D most usually several 2-D “cuts” in principle planes 8 .. RadiationRadiation patternpattern cancan bebe . Isotropic Equal radiation in all directions (not physically realizable, but valuable for comparison purposes) . Directional Radiates (or receives) more effectively in some directions than in others . Omni-directional nondirectional in azimuth, directional in elevation 9 ..PrinciplePrinciple patternspatterns . E-plane . H-plane Plane defined by H-field and Plane defined by E-field and direction of maximum direction of maximum radiation radiation (usually coincide with principle planes of the coordinate system) 10 Coordinate System Fig. 2.1 Coordinate system for antenna analysis. 11 ..RadiationRadiation patternpattern lobeslobes . Major lobe (main beam) in direction of maximum radiation (may be more than one) . Minor lobe - any lobe but a major one . Side lobe - lobe adjacent to major one . -
Radiometry and the Friis Transmission Equation Joseph A
Radiometry and the Friis transmission equation Joseph A. Shaw Citation: Am. J. Phys. 81, 33 (2013); doi: 10.1119/1.4755780 View online: http://dx.doi.org/10.1119/1.4755780 View Table of Contents: http://ajp.aapt.org/resource/1/AJPIAS/v81/i1 Published by the American Association of Physics Teachers Related Articles The reciprocal relation of mutual inductance in a coupled circuit system Am. J. Phys. 80, 840 (2012) Teaching solar cell I-V characteristics using SPICE Am. J. Phys. 79, 1232 (2011) A digital oscilloscope setup for the measurement of a transistor’s characteristic curves Am. J. Phys. 78, 1425 (2010) A low cost, modular, and physiologically inspired electronic neuron Am. J. Phys. 78, 1297 (2010) Spreadsheet lock-in amplifier Am. J. Phys. 78, 1227 (2010) Additional information on Am. J. Phys. Journal Homepage: http://ajp.aapt.org/ Journal Information: http://ajp.aapt.org/about/about_the_journal Top downloads: http://ajp.aapt.org/most_downloaded Information for Authors: http://ajp.dickinson.edu/Contributors/contGenInfo.html Downloaded 07 Jan 2013 to 153.90.120.11. Redistribution subject to AAPT license or copyright; see http://ajp.aapt.org/authors/copyright_permission Radiometry and the Friis transmission equation Joseph A. Shaw Department of Electrical & Computer Engineering, Montana State University, Bozeman, Montana 59717 (Received 1 July 2011; accepted 13 September 2012) To more effectively tailor courses involving antennas, wireless communications, optics, and applied electromagnetics to a mixed audience of engineering and physics students, the Friis transmission equation—which quantifies the power received in a free-space communication link—is developed from principles of optical radiometry and scalar diffraction. -
Improving Wireless LAN Antenna Gain and Coverage
APPLICATION NOTE Improving Wireless LAN Antenna Gain and Coverage antenna, which can help mitigate interference between floors. The only drawback is that the longer antenna may be somewhat less aesthetic. Mounting a dipole antenna on a conductive ground plane has a similar effect as using a longer antenna. The elevation pattern is flattened, creating higher gain around the perimeter of the doughnut. Additionally, the ground plane mounted antennas pattern is maximized downward slightly (if the antenna is mounted beneath a ceiling ground plane). This is an ideal elevation pattern for a ceiling mounted antenna in a multi-story building. The ground plane has the effect of minimizing gain below and especially above Most of the antennas provided with Wi-Fi the antenna. access points, or purchased separately, are simple dipole antennas with an omni- Wi-Fi antennas may be classified as ground directional pattern. Omni-directional means plane dependent and ground plane that the gain is the same in a 360º circle independent. The ground plane dependent around the axis of the antenna. antenna must be mounted on a conductive, flat ground plane which is several However, the elevation gain pattern is wavelengths long and wide in order to different. In cross section, the elevation provide the rated gain and impedance pattern is that of a doughnut, with the match. The ground plane independent antenna axis running through the center of antenna does not need to be mounted on a the doughnut. In the absence of a ground ground plane to provide the rated gain and plane, the gain of the dipole is a maximum impedance match. -
25. Antennas II
25. Antennas II Radiation patterns Beyond the Hertzian dipole - superposition Directivity and antenna gain More complicated antennas Impedance matching Reminder: Hertzian dipole The Hertzian dipole is a linear d << antenna which is much shorter than the free-space wavelength: V(t) Far field: jk0 r j t 00Id e ˆ Er,, t j sin 4 r Radiation resistance: 2 d 2 RZ rad 3 0 2 where Z 000 377 is the impedance of free space. R Radiation efficiency: rad (typically is small because d << ) RRrad Ohmic Radiation patterns Antennas do not radiate power equally in all directions. For a linear dipole, no power is radiated along the antenna’s axis ( = 0). 222 2 I 00Idsin 0 ˆ 330 30 Sr, 22 32 cr 0 300 60 We’ve seen this picture before… 270 90 Such polar plots of far-field power vs. angle 240 120 210 150 are known as ‘radiation patterns’. 180 Note that this picture is only a 2D slice of a 3D pattern. E-plane pattern: the 2D slice displaying the plane which contains the electric field vectors. H-plane pattern: the 2D slice displaying the plane which contains the magnetic field vectors. Radiation patterns – Hertzian dipole z y E-plane radiation pattern y x 3D cutaway view H-plane radiation pattern Beyond the Hertzian dipole: longer antennas All of the results we’ve derived so far apply only in the situation where the antenna is short, i.e., d << . That assumption allowed us to say that the current in the antenna was independent of position along the antenna, depending only on time: I(t) = I0 cos(t) no z dependence! For longer antennas, this is no longer true. -
Open Bradley Sherman Spring 2014.Pdf
THE PENNSYLVANIA STATE UNIVERSITY SCHREYER HONORS COLLEGE DEPARTMENT OF ELECTRICAL ENGINEERING HIGH FREQUENCY ANTENNA COUPLING STUDY BRADLEY SHERMAN SPRING 2014 A thesis submitted in partial fulfillment of the requirements for a baccalaureate degree in Electrical Engineering with honors in Electrical Engineering Reviewed and approved* by the following: James K. Breakall Professor of Electrical Engineering Thesis Supervisor John D. Mitchell Professor of Electrical Engineering Honors Adviser Keith A. Lysiak Senior Research Associate Thesis Reader * Signatures are on file in the Schreyer Honors College. i ABSTRACT The objective of this project was to develop a methodology to accurately predict antenna coupling through the use of numerical electromagnetic modeling. A high-frequency (HF) ionospheric sounder is being developed for HF propagation studies. This sounder requires high power transmissions on one antenna while receiving on another antenna. In order to minimize the coupling of high power energy back into the receiver, the transmit and receive antenna coupling must be minimized. The results of this research effort have shown that the current antenna setup can be improved by choosing a co-polarization setup and changing the frequency to 6.78 MHz. Rotating the receive antenna so that it runs parallel to the receive antenna decreases the antenna coupling by 8 dB. Typically the cross-polarization created by putting two antennas perpendicular to each other would decrease the antenna coupling dramatically, but that does not work if the feeds are along the perpendicular access. Attaining the ideal perpendicular setup is not possible in this case due to space restrictions. ii TABLE OF CONTENTS List of Figures ......................................................................................................................... -
Development of Earth Station Receiving Antenna and Digital Filter Design Analysis for C-Band VSAT
INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 3, ISSUE 6, JUNE 2014 ISSN 2277-8616 Development of Earth Station Receiving Antenna and Digital Filter Design Analysis for C-Band VSAT Su Mon Aye, Zaw Min Naing, Chaw Myat New, Hla Myo Tun Abstract: This paper describes the performance improvement of C-band VSAT receiving antenna. In this work, the gain and efficiency of C-band VSAT have been evaluated and then the reflector design is developed with the help of ICARA and MATLAB environment. The proposed design meets the good result of antenna gain and efficiency. The typical gain of prime focus parabolic reflector antenna is 30 dB to 40dB. And the efficiency is 60% to 80% with the good antenna design. By comparing with the typical values, the proposed C-band VSAT antenna design is well optimized with gain of 38dB and efficiency of 78%. In this paper, the better design with compromise gain performance of VSAT receiving parabolic antenna using ICARA software tool and the calculation of C-band downlink path loss is also described. The particular prime focus parabolic reflector antenna is applied for this application and gain of antenna, radiation pattern with far field, near field and the optimized antenna efficiency is also developed. The objective of this paper is to design the downlink receiving antenna of VSAT satellite ground segment with excellent gain and overall antenna efficiency. The filter design analysis is base on Kaiser window method and the simulation results are also presented in this paper. Index Terms: prime focus parabolic reflector antenna, satellite, efficiency, gain, path loss, VSAT. -
Design and Implementation of T-Shaped Planar Antenna for MIMO Applications
Computers, Materials & Continua Tech Science Press DOI:10.32604/cmc.2021.018793 Article Design and Implementation of T-Shaped Planar Antenna for MIMO Applications T. Prabhu1,* and S. Chenthur Pandian2 1Department of ECE, SNS College of Technology, Coimbatore, 641035, Tamil Nadu, India 2Department of EEE, SNS College of Technology, Coimbatore, 641035, Tamil Nadu, India *Corresponding Author: T. Prabhu. Email: [email protected] Received: 21 March 2021; Accepted: 26 April 2021 Abstract: This paper proposes, demonstrates, and describes a basic T-shaped Multi-Input and Multi-Output (MIMO) antenna with a resonant frequency of 3.1 to 10.6 GHz. Compared with the U-shaped antenna, the mutual coupling is minimized by using a T-shaped patch antenna. The T-shaped patch antenna shapes filter properties are tested to achieve separation over the 3.1 to 10.6 GHz frequency range. The parametric analysis, including width, duration, and spacing, is designed in the MIMO applications for good isolation. On the FR4 substratum, the configuration of MIMO is simulated. The appropriate dielec- tric material εr = 4.4 is introduced using this contribution and application array feature of the MIMO systems. In this paper, FR4 is used due to its high dielectric strength and low cost. For 3.1 to 10.6 GHz and 3SRR, T-shaped patch antennas are used in the field to increase bandwidth. The suggested T- shaped MIMO antenna is calculated according to the HFSS 13.0 program simulation performances. The antenna suggested is, therefore, a successful WLAN candidate. Keywords: Multi-input and multi-output; FR4 substratum; t-shaped patch antennas; ISM band; HFSS 13.0; WLAN 1 Introduction Multiple Input and Multiple Output (MIMO) devices can send and receive simultaneous signaling at the same power level and maximize high data rate demands in modern communication systems. -
Methods for Measuring Rf Radiation Properties of Small Antennas
Helsinki University of Technology Radio Laboratory Publications Teknillisen korkeakoulun Radiolaboratorion julkaisuja Espoo, October, 2001 REPORT S 250 METHODS FOR MEASURING RF RADIATION PROPERTIES OF SMALL ANTENNAS Clemens Icheln Dissertation for the degree of Doctor of Science in Technology to be presented with due permission for public examination and debate in Auditorium S4 at Helsinki University of Technology (Espoo, Finland) on the 16th of November 2001 at 12 o'clock noon. Helsinki University of Technology Department of Electrical and Communications Engineering Radio Laboratory Teknillinen korkeakoulu Sähkö- ja tietoliikennetekniikan osasto Radiolaboratorio Distribution: Helsinki University of Technology Radio Laboratory P.O. Box 3000 FIN-02015 HUT Tel. +358-9-451 2252 Fax. +358-9-451 2152 © Clemens Icheln and Helsinki University of Technology Radio Laboratory ISBN 951-22- 5666-5 ISSN 1456-3835 Otamedia Oy Espoo 2001 2 Preface The work on which this thesis is based was carried out at the Institute of Digital Communications / Radio Laboratory of Helsinki University of Technology. It has been mainly funded by TEKES and the Academy of Finland. I also received financial support from the Wihuri foundation, from HPY:n Tutkimussäätiö, from Tekniikan Edistämissäätiö, and from Nordisk Forskerutdanningsakademi. I would like to thank all these institutions, and the Radio Laboratory, for making this work possible for me. I am especially thankful for the many ideas and helpful guidance that I got from my supervisor professor Pertti Vainikainen during all my work. Of course I would also like to thank the staff of the Radio Laboratory, who provided a pleasant and inspiring working atmosphere, in which I got lots of help from my colleagues - let me mention especially Stina, Tommi, Jani, Lorenz, Eino and Lauri - without whom this work would not have been possible. -
Application Note AN-00502
Proper PCB Design for Embedded Antennas Application Note AN-00502 Introduction Embedded antennas are ideal for products that cannot use an external antenna. The reasons for this can range from ergonomic or aesthetic reasons or perhaps the product needs to be sealed because it is to be used in a rough environment. It could also simply be based on cost. Whatever the reason, embedded antennas are a popular solution. Embedded antennas are generally quarter wave monopole antennas. These are only half of the antenna structure with the other half being a ground plane on the product’s circuit board. The details of antenna operation are beyond the scope of this application note, but suffice it to say that the layout of the PCB becomes critical to the RF performance of the product. Common PCB Layout Guidelines While each antenna style has specific requirements, there are some requirements that are common to all of them. • Use a manufactured board for testing the antenna performance. RF is very picky and perf boards or other “hacked” boards will at best give Figure 1: Linx Embedded Antennas a poor indication of the antenna’s true performance and at worst will simply not work. Each antenna has a recommended layout that should be followed as closely as possible to get the performance indicated in the antenna’s data sheet. Most Linx antennas have an evaluation kit that includes a test board, so please contact us for details. • The antenna should, as much as reasonably possible, be isolated from other components on your PCB, especially high-frequency circuitry such as crystal oscillators, switching power supplies, and high-speed bus lines. -
Design Considerations for Mixed-Signal PCB Layout
Design Considerations for Mixed-Signal PCB Layout Application Note 1. Introduction This application note aims at providing you with some recommendations to achieve better performance from the ADC. The initial assumptions are the following: • Proper grounding and routing of all signals is essential to ensure accurate signal conversion • Eliminate the loop area return by using both separate ground plane and power plane • Circuitry placement on mixed-signal PCBs is a crucial design point In many cases, engineers have preconceived notions about mixed-signal designs and how analog and digital placement, partitioning and associated design should be performed. When laying out components for a mixed-signal PCB, certain considerations are critical to achieve opti- mum performance. Mixed-signal PCB’s are particularly tricky to design since analog devices possess different characteristics compared to digital components: different power rating, current, voltage and heat dissipation requirements, to name a few. This study shows how to prevent digital logic ground currents from contaminating analog circuitry on a mixed-signal PCB and particularly ADC component. In our attempt to answer this question, let’s keep in mind two basic principles of electromagnetic compat- ibility. One is that currents should be returned to their source as locally and compactly as possible, through the smallest possible loop area. The second is that a system should have only one reference plane, if not we would create a dipole antenna. Visit our website: www.e2v.com for the latest version of the datasheet e2v semiconductors SAS 2010 0999B–BDC–08/10 Design Considerations for Mixed-Signal PCB Layout 2.