Measurement of Loudspeaker Directivity
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Design of a System for Cm-Range Wireless Communication
Design of a system for cm-range wireless communication Simone Gambini Jan M. Rabaey Elad Alon Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2009-184 http://www.eecs.berkeley.edu/Pubs/TechRpts/2009/EECS-2009-184.html December 18, 2009 Copyright © 2009, by the author(s). All rights reserved. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission. Design of a system for cm-range wireless communications by Simone Gambini A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Electrical Engineeing and Computer Sciences in the GRADUATE DIVISION of the UNIVERSITY OF CALIFORNIA, BERKELEY Committee in charge: Professor Jan Rabey, Chair Professor Elad Alon Professor Paul K. Wright Fall 2009 The dissertation of Simone Gambini is approved. Chair Date Date Date University of California, Berkeley Fall 2009 Design of a system for cm-range wireless communications Copyright c 2009 by Simone Gambini Abstract Design of a system for cm-range wireless communications by Simone Gambini Doctor of Philosophy in Electrical Engineeing and Computer Sciences University of California, Berkeley Professor Jan Rabey, Chair The continuous growth in the number of mobile phone subscribers, which exceeded 3 billions by 2007 , and of the number of wireless devices and systems, led to visions of a near future in which wireless technology is so ubiquitous that 1000 Radios per person will exist. -
LIT9785 RFA/PWR-14X
RFA-14x ® ® car audiofor RFR-14x Tweeters fanatics Operation & Installation RFA-14x PWR-14x power ® Dear Customer, Congratulations on your purchase of the world's finest brand of car audio speakers. At Rockford Fosgate we are fanatics about musical reproduction at its best, and we are pleased you chose our product. Through years of engineering expertise, hand craftsman- ship and critical testing procedures, we have created a wide range of products that reproduce music with all the clarity and richness you deserve. For maximum performance we recommend you have your new Rockford Fosgate product installed by an Authorized Rockford Fosgate Dealer, as we provide specialized training through Rockford Technical Training Institute (RTTI). Please read your warranty and retain your receipt and original carton for possible future use. Great product and competent installations are only a piece of the puzzle when it comes to your system. Make sure that your installer is using 100% authentic installation accessories from Connecting Punch in your installation. Connecting Punch has everything from RCA cables and speaker wire to Power line and battery connectors. Insist on it! After all, your new system deserves nothing but the best. To add the finishing touch to your new Rockford Fosgate image order your Rockford wearables, which include everything from T-shirts and jackets to hats and sunglasses. To get a free brochure on Rockford Fosgate products and Rockford wearables, in the U.S. call 602-967-3565 or FAX 602-967-8132. For all other countries, call +001-602- 967-3565 or FAX +001-602-967-8132. PRACTICE SAFE SOUND™ CONTINUOUS EXPOSURE TO SOUND PRESSURE LEVELS OVER 100dB MAY CAUSE PERMANENT HEARING LOSS. -
Antenna Gain Measurement Using Image Theory
i ANTENNA GAIN MEASUREMENT USING IMAGE THEORY SANDRAWARMAN A/L BALASUNDRAM A project report submitted in partial fulfillment of the requirement for the award of the degree Master of Electrical Engineering Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn Malaysia JANUARY 2014 v ABSTRACT This report presents the measurement result of a passive horn antenna gain by only using metallic reflector and vector network analyzer, according to image theory. This method is an alternative way to conventional methods such as the three antennas method and the two antennas method. The gain values are calculated using a simple formula using the distance between the antenna and reflector, operating frequency, S- parameter and speed of light. The antenna is directed towards an absorber and then directed towards the reflector to obtain the S11 parameter using the vector network analyzer. The experiments are performed in three locations which are in the shielding room, anechoic chamber and open space with distances of 0.5m, 1m, 2m, 3m and 4m. The results calculated are compared and analyzed with the manufacture’s data. The calculated data have the best similarities with the manufacturer data at distance of 0.5m for the anechoic chamber with correlation coefficient of 0.93 and at a distance of 1m for the shield room and open space with correlation coefficient of 0.79 and 0.77 but distort at distances of 2m, 3m and 4m at all of the three places. This proves that the single antenna method using image theory needs less space, time and cost to perform it. -
Design of a Class of Antennas Utilizing MEMS, EBG and Septum Polarizers Including Near-Field Coupling Analysis
UNIVERSITY OF CALIFORNIA Los Angeles Design of a Class of Antennas Utilizing MEMS, EBG and Septum Polarizers including Near-field Coupling Analysis A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Electrical Engineering by Ilkyu Kim 2012 c Copyright by Ilkyu Kim 2012 ABSTRACT OF THE DISSERTATION Design of a Class of Antennas Utilizing MEMS, EBG and Septum Polarizers including Near-field Coupling Analysis by Ilkyu Kim Doctor of Philosophy in Electrical Engineering University of California, Los Angeles, 2012 Professor Yahya Rahmat-Samii, Chair Recent developments in mobile communications have led to an increased appearance of short-range communications and high data-rate signal transmission. New technologies provides the need for an accurate near-field coupling analysis and novel antenna designs. An ability to effectively estimate the coupling within the near-field region is required to realize short-range communications. Currently, two common techniques that are applicable to the near-field coupling problem are 1) integral form of coupling formula and 2) generalized Friis formula. These formulas are investigated with an emphasis on straightforward calculation and accuracy for various distances between the two antennas. The coupling formulas are computed for a variety of antennas, and several antenna configurations are evaluated through full-wave simulation and indoor measurement in order to validate these techniques. In addition, this research aims to design multi- functional and high performance antennas based on MEMS (Microelectromechanical ii Systems) switches, EBG (Electromagnetic Bandgap) structures, and septum polarizers. A MEMS switch is incorporated into a slot loaded patch antenna to attain frequency reconfigurability. -
A Prototype Model Design of Wideband Standard Reference Rod- Dipole Antenna for 3-Axial EMC Measurement with Hybrid Balun for 0.9 to 3.2Ghz Range
ADVANCED ELECTROMAGNETICS, VOL. 7, NO. 1, FEBRUARY 2018 A Prototype Model Design of Wideband Standard Reference Rod- Dipole Antenna for 3-Axial EMC Measurement with Hybrid Balun for 0.9 to 3.2GHz Range. Sarang Patil1, Peter Petkov2, Boncho Bonev3 1SKN Sinhgad Institute of Technology & Science, Lonavala, Maharashtra, India 2, 3 Department of RCVT, Technical University of Sofia, Sofia, Bulgaria E-mail: [email protected] Abstract Compliance test at open field site testing for manufacturing Every electronics equipment must deal with EMC test. The end. testing laboratory of electronics equipment for radiation emission must have accurately calibrated antennas. The To measure all three components of electric field vector, a field strength of total radiated radio frequency is average of tailor-made antenna type called "Tri-pole" is most beneficial all incident signals at given point; this incident signal over conventional antenna; different EM wave field was originates from various directions. To measure three measuring antenna with the comparison is discussed in components of all-electric field vectors, a tri-pole antenna is previous work [1].The simple structure symmetric balanced most beneficial over conventional antenna because of it half-wave dipole used for various applications, it provides responds to signal coming from multi-directions. This paper useful electrical characteristics but a narrow band, this presents novel three axis wideband calculable rod-dipole problem is solved in [2]. antenna with the hybrid balun for the range of 900MHz to 3.2GHz frequencies, the proposed antenna is small in size Antenna designing is the hot topic for E-field probe, various and functional electrical characteristics. -
Near Field Quasi-Null Control and Far Field Sidelobe Level Maintenance
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Repositorio da Universidade da Coruña NEAR FIELD QUASI-NULL CONTROL WITH FAR FIELD SIDELOBE LEVEL MAINTENANCE IN LINE SOURCE DISTRIBUTIONS J. C. Brégains, F. Ares, and E. Moreno Grupo de Sistemas Radiantes, Departamento de Física Aplicada, Facultad de Física, Universidad de Santiago de Compostela. 15782 - Santiago de Compostela – Spain [email protected] ABSTRACT An improving method -based on Taylor line source- that allocates a quasi-null in a specified angular position of near field pattern, and, simultaneously, controls the general topography of far-field sidelobe level -without significantly loss of directivity, compared with optimal effi- ciency Taylor distribution, of the latter- is presented in this article. The method is based on the application of the Simulated Annealing technique, by achieving the complex roots of the pattern distribution. An example developed below demonstrates this accomplishment. 1. INTRODUCTION In some antenna applications it is necessary the reduction of the field magnitude in a particu- lar angular position; either, for example, to avoid the radiation in a certain specific direction, or the reception of the signal in order to keep it away from some interference, null controlling is widely applied by antenna’s designers. Previous papers [1-3] indicate that some authors 1 have achieved null controlling or steering but only using far field patterns. These examples do not face the problem of near field radiation (or reception), so the named results have not the capability neither to avoid the perturbation caused by obstacles close to the antenna, nor radi- ating with undesired relatively high power in an certain angular position at the neighborhood of it. -
How to Measure All Types of Antennas Using Very-Near-Field Measurement by Ruska Patton, Director, Product Management and Ning Yang, Principal Antenna Engineer
How to Measure All Types of Antennas Using Very-Near-Field Measurement by Ruska Patton, Director, Product Management and Ning Yang, Principal Antenna Engineer RFxpert test result CTIA Chamber test result How to Measure All Types of Antennas Using Very-Near-Field Measurement Introduction Antennas that fail to meet specified design criteria, regulatory requirements or consumer satisfaction either rapidly find the scrap heap or cause costly delays. If the antenna in question actually makes it to market and consumers identify a problem, it can create a widespread public relations nightmare. Designers therefore need to characterize an antenna to meet performance criteria including desired frequency, gain, bandwidth, impedance, efficiency and polarization. Traditional antenna characterization requires full-fledged far-field testing or gathering near-field data sets to project far-field patterns. Unfortunately, the planar sampling mode, the fastest and least costly traditional near- or far-field technique, only generates reliable results for directional antennas. Omnidirectional antennas must currently be sampled in spherical mode in a sufficiently large shielded test chamber to overcome potential sensor coupling. For an omnidirectional antenna under test (AUT), such a system also requires a three-axis (X, Y, and Z) robot system and many sampling points. Every traditional antenna testing method thus requires a trained technician and a large shielded chamber. These requirements prove costly both as a capital outlay and an ongoing operations expense. To overcome these hurdles, a novel very-near-field technology based on a probe array samples the AUT on a plane surface at a distance of 2.5 cm. The AUT can be either directional or omnidirectional. -
Guest Editorial Special Issue on IEEE RFID 2018 Conference
IEEE JOURNAL OF RADIO FREQUENCY IDENTIFICATION, VOL. 3, NO. 1, MARCH 2019 1 Guest Editorial Special Issue on IEEE RFID 2018 Conference ADIO Frequency Identification (RFID) is a generic term and 3500 IEEE journal and conference publications (all with R for a variety of active and passive RF technologies the term “RFID” in their titles), which serve to underline the that wirelessly convey object identification information. RFID rapid growth of the field. technologies encompass multiple frequency bands and differ- In 2017, IEEE launched a new IEEE JOURNAL OF RADIO ent mechanisms of information transfer: Low Frequency (LF) FREQUENCY IDENTIFICATION (JRFID). Each year, the jour- and High Frequency (HF) RFID tags typically use inductive nal features a special issue that presents a collection of coupling, Ultra-High Frequency (UHF) and microwave RFID extended papers from that year’s IEEE RFID conference. typically use electromagnetic wave propagation although they Papers in this special issue are extended versions of paper and often operate in near-field application scenarios as well. RFID poster presentations that were featured in IEEE RFID 2018, transponders have varying degrees of sophistication and their a highly competitive premier technical conference on RFID design is often a tradeoff between functionality and cost. At that took place in Orlando, FL on April 10-12, 2018. The one end of the spectrum, there are active RFID tags that offer four papers presented in this issue are written by researchers on-board battery and memory, sensor integration, active RF from three countries: Germany, India and the USA. The top- transmitter and hence communication range up to kilometers ics of this paper include crowd size estimation, antenna design albeit at increased costs. -
Field Optimization Using Segmented Patch Antennas at High Frequencies
International Journal of Recent Technology and Engineering (IJRTE) ISSN: 2277-3878, Volume-8 Issue-4, November 2019 Field Optimization using Segmented Patch Antennas at High Frequencies Mohammed Nayeemuddin, P. Karpagavalli there are many more research operations going on in Abstract: in recent day’s communication technology has this field for further reducing the antenna bandwidth, gain, increased in every field where in antenna propagation magnetic distribution of field, polarized operation and many transmission of signals to the other end is dependent on more parameters are considered. antennas. This propagation should be appropriate in both the fields as near and far fields for effectively covering which RFIDs are used which abbreviate as radio frequency identification II. ANTENNA DESIGN which are considered as reader antenna developed for operating For near field systems of RFID we use these Loop in near and far fields with high frequency band range. Here in this paper segmented loop designed of patch antenna is antennas commonly for inductive coupling. For making developed and the fabrication of antenna is done where the this loop electrically small at both the frequencies such as frequency range will be 900 MHz approximately with coefficient low and high band where its very minimum to use physical of reflection as less than 8dB which covers major UHB loop. Among the amplitude and phase distribution of frequency range of band. It has linearly polarized pattern of current is common with such a loop is uniform. So, near radiation which provides gain of 6dBi and the capacity of the loop an uniform and strong magnetic field is produced reading of antenna is from 12-15m for both the applications of in near region of loop. -
Compact Loop Antenna for Near-Field and Far-Field Uhf Rfid Applications
Progress In Electromagnetics Research C, Vol. 37, 171{182, 2013 COMPACT LOOP ANTENNA FOR NEAR-FIELD AND FAR-FIELD UHF RFID APPLICATIONS Xiaozheng Lai1, *, Zeming Xie2, and Xuanliang Cen2 1School of Computer Science & Engineering, South China University of Technology, Guangzhou 510006, China 2School of Electronic & Information, South China University of Technology, Guangzhou 510641, China Abstract|A novel type of radio frequency identi¯cation (RFID) reader antenna is proposed for mobile ultra-high frequency (UHF) RFID device. By folded-dipole loop structure with parasitic element, a small antenna size of 31 ¤ 31 ¤ 1:6 mm3 is achieved. The antenna with di®erent parasitic element size can work on di®erent UHF RFID bands. The antenna prototype is fabricated and the measured bandwidth is around 13.5 MHz (915.5{929 MHz), which covers the China RFID Band (920{925 MHz). The measured reading distance achieves 65 mm with the near-¯eld RFID tag and 1.17 m with the far-¯eld tag. The measurement agrees well with simulated result and shows that antenna is desirable for both near-¯eld and far-¯eld UHF RFID applications. 1. INTRODUCTION Radio-frequency-identi¯cation (RFID) technology has received a lot of attention in warehouse, supply chain, industry, and commerce [1]. As RFID deployment moves from pallet level to item level, it is necessary to identify and track objects by RFID tags at anytime and anywhere. Then, mobile RFID device has advantages in terms of cost, portability and wireless communication. Mobile RFID device is de¯ned as a compact RFID reader into a mobile phone, which provides diverse services through mobile communication networks [2]. -
Winter 2018 Revel Is a Unique Loudspeaker Company
Winter 2018 Revel is a unique loudspeaker company that exists for the design and production of using off-the-shelf transducers. Most were no such research existed, the Harman innovative, no-compromise products that using transducers from OEM sources that Corporate Acoustics Research Group — a expand the performance envelope of home would allow very limited customization. A group of researchers and engineers world- sound reproduction. manufacturer could ask for performance wide that are unquestionably without peer in targets, but the vendor would essentially the loudspeaker industry — do the research Revel was launched as a distinguished ‘choose a voice coil from column A and a required for us to make the world’s finest Harman International brand in January spider from column B,’ and the manufacturer loudspeakers. 1996, when company Chairman Dr. Sidney would have to take what they could get. Harman asked Kevin Voecks, now Product Revel has been in the enviable position from Revel was the first brand to embrace the Development Manager, of HARMAN Luxury the start of having extraordinarily talented multi-channel listening lab approach to Audio Group, to create the world’s finest transducer engineers who design each of our testing, where double-blind listening tests loudspeakers, period — no strings attached. drivers from the ground up to be ideally suited have been refined to such a degree that "Indeed, Dr. Harman remained true to his for each specific application. Revel has led the results yield repeatable metrics, rather word, never attempting to influence Revel’s the way with innovative transducers that allow than the unreliable and unverifiable results technical or sonic direction," notes Voecks. -
PRODUCT GUIDE Table of Contents
PRODUCT GUIDE Table of Contents “We are integrators building FastLoc pg. 2 products for integrators.” pg. 4 – Sean McDermott, CEO FIT CS pg. 6 Bipole/Dipole pg. 8 Dual Tweeter pg. 10 Great design, integration, and excellence in manufacturing all play critical roles in creating Current Audio products. InWall pg. 12 Current Audio is backed by an award winning and inspiring team of seasoned designers, engineers, and installation experts, LCR pg. 14 holding title as CE Pro Top 100 Integrators with years of patented, custom audio product development, manufacturing and pg. 16 experience. CECS ProSeries pg. 18 You don’t have to go far to see how the electronics industry has changed over the last few decades but what can we say about the actual speakers? Subwoofer pg. 20 pg. 22 With decades of sales and installation know-how in the speaker business, as integrators we Outdoor understand the installers’ wants, needs, and struggles because we are installers ourselves. ILS pg. 24 pg. 25 Current Audio presents proven and innovative products that excel in quality and performance Amp which will save you time and money. We carefully listen to and respond to our customers’ Bracket pg. 26 suggestions and needs. The result of our listening has modeled a superior company and product line. SpeKap/WWP pg. 27 pg. 28 Current Audio is holder of fifteen international patents. This is a true testament of our Transformer determination to bring a fresh set of innovative ideas to what has become known as stagnant part of the industry. Speaker Selector/Volume Control pg.