Easy Antennas for the SWL
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ANTENNAS for LOW POWER APPLICATIONS Basic Full
ANTENNAS FOR LOW POWER APPLICATIONS By Kent Smith Introduction: There seems to be little information on compact antenna design for the low power wireless field. Good antenna design is required to realize good range performance. A good antenna requires it to be the right type for the application. It also must be matched and tuned to the transmitter and receiver. To get the best results, a designer should have an idea about how the antenna works, and what the important design considerations are. This paper should help to achieve effective antenna design. Some Terms: Wavelength; Important for determination of antenna length, this is the distance that the radio wave travels during one complete cycle of the wave. This length is inversely proportional to the frequency and may be calculated by: wavelength (cm)=30000 / frequency (Mhz). Groundplane; A solid conductive area that is an important part of RF design techniques. These are usually used in transmitter and receiver circuits. An example is where most of the traces will be routed on the topside of the board, and the bottom will be a mostly solid copper area. The groundplane helps to reduce stray reactances and radiation. Of course, the antenna line needs to run away from the groundplane. dB, or decibel; A logarithmic scale used to show power gain or loss in an rf circuit. +3 dB is twice the power, while -3 dB is one half. It takes 6 dB to double or halve the radiating distance, due to the inverse square law. The Basic Antenna, and how it works. An antenna can be defined as any wire, or conductor, that carries a pulsing or alternating current. -
Investigating Energy Harvesting Technology to Wirelessly Charge Batteries of Mobile Devices
Investigating energy harvesting technology to wirelessly charge batteries of mobile devices By Neetu Ramsaroop (19751797) Submitted in fulfilment of the requirements of the Master of Information and Communications Technology degree In the Department of Information Technology in the Faculty of Accounting and Informatics Durban University of Technology Durban, South Africa July, 2017 DECLARATION I, Neetu Ramsaroop, declare that this dissertation represents my own work and has not been previously submitted in any form for another degree at any university or institution of higher learning. All information cited from published and unpublished works have been acknowledged. ________________________ ____________________________ Student Date Approved for final submission Supervisor: ___________________________ ____________________________ Prof. O. O. Olugbara Date Co-supervisors: ___________________________ ____________________________ Esther D. Joubert Date i DEDICATION To My family and my supportive friends ii ACKNOWLEDGMENTS I am grateful to God for embracing me with the strength and inspiration all through this research journey. My sincere gratitude is accorded to my Supervisor, Professor O.O. Olugbara, for his dedication, academic knowledge, expertise, guidance, patience, direction, feedback, comments and meticulous checking of this study. Not to mention his “reminder” phone calls to keep me in check. I would also like to express my deepest appreciation to my Co-Supervisor, Mrs Esther Joubert, for her dedication, constant encouragement, guidance, motivation, outstanding academic writing, patience with my messages at odd hours, dealing with my panic moments and the pleasant manner in which she provided direction in this study. I am thankful to all my friends, DUT colleagues and work colleagues for their support, motivation and advice during this work. -
MFJ-16010 Random Wire Antenna Tuner Thank You for Purchasing the MFJ-16010 Random Wire Antenna Tuner
MFJ-16010 Random Wire Antenna Tuner Thank you for purchasing the MFJ-16010 Random Wire Antenna Tuner. GENERAL INFORMATION The MFJ-16010 is a variable L-network designed to match the low output impedance of your transmitter to the high impedance of a random wire (or vice versa). It will match almost any random length of wire to any transmitter from 160 thru 10 meters. The transmitter may have an output RF power up to 200 watts. For best results, the random wire should be as long, high, and clear of surrounding objects as possible. Do not ground the random wire antenna. The connectors are labeled properly to match a transmitter to a higher impedance. This is the normal connection. To match impedances that are lower than your transmitter impedance (such as a mobile whip), simply interchange the normal transmitter and antenna connections to the MFJ-16010. Remember the MFJ-16010 is designed to match a single random wire and not a coaxial line, even though coaxial connectors are used for both antenna and transmitter connections (these connectors make it easy to interchange antenna and transmitter connections). A standard banana plug will fit nicely into the center of the S0-239 coaxial connector and can be used to connect the single random wire in lieu of a coaxial plug (PL-239). A standard coaxial cable having an impedance that matches your transmitter output impedance, should be used to connect your transmitter to the MFJ16010. Make sure the MFJ-16010 is well grounded to the transmitter. If you are using the MFJ-16010 to match a vertical or mobile whip, the tuner needs to be at the feed point of the antenna and not at the transmitter end of the coaxial transmission line. -
Which HF Antenna Should I Get?
Brass Tacks An in-depth look at a radio-related topic Which HF antenna should I get? You’ve earned your General class license, and now you’re thinking of entering the wide world of HF (high frequency), which is ironically low frequency com- pared with much of the remaining amateur realm. Af- ter posting controversial questions on Facebook, you’ve finally decided on a very pretty, feature-rich HF rig, one that’s supposed to deliver 100 watts to the airwaves, and maybe includes a built-in tuner. Being the educated ham you are, you already know what coaxial cable to pur- chase, and maybe even the connectors you’re going to need. But that education has also taught you that you now face the most important question of all: which antenna? The decision about your HF antenna choice is not a trivial one. Some things to consider include home space restrictions, aesthet- ics (whether it looks nice with your home), and price. Ok, if money was no object, let’s go straight for the jugular, shall we? You want a 200-foot Rohn tower, a Yaesu rotator system, Cushcraft X7 beam antenna, with the X-740 add-on, all connected by Heliax. Well, you can dream, right? In reality, you live under the thumb of an HOA, your spouse will gladly allow an invisible antenna, and you only have $59 to spend on it. So, the goal is to get into HF ter- ritory within the limits specified by our environment. Not always easy, so let’s break this down, and then arm you with the infor- mation you need to make an informed decision about where to go next. -
Antenna Articles Collection of Short Articles Relating to All Manners of Antennas
Antenna Tips page 1 of 31 Source : http://www.funet.fi/pub/dx/text/antennas/antinfo.txt Antenna Articles Collection of short articles relating to all manners of antennas. These articles are the hard work of Wayne Sarosi KB4YLY (995 Alabama Street, Titusville, FL 32796) SUBJECT: Circular Polarized Antenna There has been a request for a series on 'CP' antennas. The term 'CP' eluded me at first as I was not familar with the abriviated designator for circular polarization. At work, we just use the entire words. I'm going to begin this ten part series with the basics. After researching CP designs with a few engineers and fellow hams, I found that they knew very little about the subject. I also found I didn't know quite as much as I thought I did about circular polarization. So starting at the begining will help all out. First, let's discuss the circular polarized wave. There seems to be conflicting standards used by the world of physics and the IEEE. I found this to be true in four reference manuals including the ARRL Antenna Handbook. At least it's stated right up front but biased according to which text you read. We will follow the IEEE/ARRL standard in the following series for obvious reasons. There are two types of circular polarization; right and left. All of us agree up to this point. According to the ARRL Antenna Handbook, the following statement: 'Polarization Sense is a critical factor, especially in EME work or if the satellite uses a circular polarized antenna. -
MFJ 2004 Ham Buyers Guide
QSTCatP01.qxd 10/16/2003 10:03 AM Page 1 MFJ 2004 Ham Buyers Guide See inside for these New MFJ Products! 300W Automatic Tuner Tiny Travel Tuner DC Multi-Outlet Strips Ultra-fast, 2000 memories, antenna Fits in the palm of your hand! 150 has both 5-way binding posts switch, 4:1 balun, Cross-Needle and Watts, 80-10 Meters, Bypass Switch and Digital SWR/Wattmeter, 1.8-30 MHz Anderson PowerPole® connectors MFJ-902 $7995 $ 95 MFJ-1129 $ 95 109 MFJ-993 259 Four New models -- balun, Four new high current 150, 300, 600 Watt models. SWR/Wattmeter . DC multi-outlet strips . See Back Cover See Page 6 See Page 16 Balanced Line Dummy Load Manual Mic/Radio Switch Antenna Tuner SWR/Wattmeter Screwdriver Switch any 2 mics 1.5kW, to any 2 rigs Superb Antenna peak reading Covers 40-2 Meters balance, switchable 1.8-54 MHz, to external MFJ-1662 $ 95 $ 95 300 Watts antenna 129 MFJ-1263 99 $ 95 $ 95 MFJ-974H 189 MFJ-267 149 Four new models . Three new models . See Page 7 See Page 9 See Page 42 See Page 21 10 foot Antenna 160-6 Meter 1.5 kW 4:1 Glazed 4 Foot Telescopic Tripod Doublet current balun ceramic Ground Whip 40-inch Antenna /insulator insulator Rod MFJ-1954 between legs Copper bonded steel MFJ- $ 95 MFJ-1918 MFJ-919 MFJ-16C01 MFJ-1934 19 1777 $ 95 $ 95 $ 95 59 $ 95 3 lengths . 39 49 69c 4 See Page 42 See Page 42 See Page 43 See Page 43 See Page 43 See Page 7 Mobile Discone Atomic Atomic Wireless Speaker/Mic Antennas Antenna 24/12 Clock 24/12 Watch Weather for Yaesu VX-7R MFJ-1456, $14995 25-1300 Station MHz 40/20/15/10/6/2M MFJ- MFJ- MFJ-295R $ 95 $ 95 MFJ-1868 132RC 186RC MFJ-192 MFJ-1438, 99 $ 95 19 10/6/2M/440 MHz $5995 $1495 $2995 59 See Page 41, 39 See Page 40 See Page 29 See Page 30 See Page 30 See Page 35 Ameritron Ameritron Ameritron Hy-Gain Screwdriver Digital Screwdriver flat Mobile 80-10 M Vertical Antenna Antenna Controller SWR/Wattmeter The Classic is Back! 5 1.2 kW, Pittman Super bright high- Just 1 /8” thick, AV-18AVQII Commercial Gear Motor intensity LEDs flat mounts on $ 95 dashboard 229 SDA-100 SDC-100 MK-80, $79.95. -
Evaluation of an Electronically Switched Directional Antenna for Real-World Low-Power Wireless Networks
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Swedish Institute of Computer Science Publications Database Evaluation of an Electronically Switched Directional Antenna for Real-world Low-power Wireless Networks Erik Ostr¨ om,¨ Luca Mottola, Thiemo Voigt Swedish Institute of Computer Science (SICS), Kista, Sweden Abstract. We present the real-world evaluation of SPIDA, an electronically swit- ched directional antenna. Compared to most existing work in the field, SPIDA is practical as well as inexpensive. We interface SPIDA with an off-the-shelf sensor node which provides us with a fully working real-world prototype. We assess the performance of our prototype by comparing the behavior of SPIDA against tradi- tional omni-directional antennas. Our results demonstrate that the SPIDA proto- type concentrates the radiated power only in given directions, thus enabling in- creased communication range at no additional energy cost. In addition, compared to the other antennas we consider, we observe more stable link performance and better correspondence between the link performance and common link quality estimators. 1 Introduction The use of external antennas is a common design choice in many deployments of low- power wireless networks [13]. Indeed, an external antenna often features higher gains compared to the antennas found aboard mainstream devices, enabling increased relia- bility in communication at no additional energy cost. To implement such design, re- searchers and domain-experts have hitherto borrowed the required technology from WiFi networks [10, 22]. This holds both w.r.t. scenarios requiring omni-directional communication [22], and where the application at hand allows directional communica- tion [10]. -
AB Antenna Family.Qxp
WIRELESS PRODUCTS Airborne™ Antenna Product Family ACH2-AT-DP000 series ACH0-CD-DP000 series (other accessories) Airborne™ Antennas are designed for connection to 802.11 wireless devices operating in the 2.4GHz ISM band. These antennas fully support the entire line of Airborne™ wireless 802.11 products. This assortment of antennas is intended to provide OEMs with solutions that meet the demanding and diverse requirements for transportation, medical, warehouse logistics, POS, industrial, military and scientific applications. Applications The Airborne™ Antenna family offers antennas for embedded applications, fixed stations, mobile operation and client side devices, and for indoor and outdoor applications. The antennas feature RP-SMA, N-type and U.FL connectors that provide the designer with flexible ways to connect to Airborne wireless products. A wide range of antenna types and gain options enable an OEM to select the antenna that best matches their application requirements. The Recommended for AirborneTM 802.11 lower gain and smaller antennas, such as the “rubber duck” antennas, would fit applications embedded and system bridge products where the range is not required to exceed 200- 400m while the higher gain directional antennas Made for Embedded or External mounting, would be suitable for extended range that require greater than 800m reach. Embedded antennas Mobile or Fixed station, and Indoor and/or provide ranges from 50m up to 300m. Outdoor operation Specialty Antenna Embedded antenna options are intended for Select from Omni Directional, Highly applications where it is not desirable to use an Directional, or Corner Reflector external antenna, or where the enclosure or application does not allow for an external antenna. -
Long Wire Antenna
ANTENNA AND WAVE PROPAGATION Long Wire Antenna Long wire or random wire antennas are very simple antennas. They can come close to half wave antennas in efficiency, although efficiency decreases as they are made very long or installed closer to earth. Technically a true "longwire" needs to be at least one wavelength long, but Hams commonly call any endfed wire a longwire or random wire antenna. Advantages & Disadvantages The antenna itself works just as well as any other wire of similar height and length. Any or all problems are in the counterpoise and feed system. The difficult problems associated with random wire or longwire antennas are caused by ground currents and radiation from the single wire feeder. Endfed antennas, or antennas with the single wire feeder brought into the shack, come with a little misconception. One commonly repeated myth or "theory" is that halfwave antennas, being resonant, do not require a counterpoise, or that some magical length of antenna will prevent RF in the shack. This does not mean the antenna will be worthless and not make contacts, it simply means something else replaces the missing counterpoise area and we also bring RF fields right into the shack. The feedline, as well as everything connected to and surrounding the singlewire feedline and counterpoise, becomes part of the radiating system. This creates three potential problems: The feedline, mast, and things around the feedline connect through the antenna into the receiver. This brings noise into the receiver. The feedline, mast, and things around the feedline become part of the radiator. This brings voltage (electric fields) and current (magnetic fields) directly into the shack. -
Recommendation Itu-R Bs.705-1*
Rec. ITU-R BS.705-1 1 RECOMMENDATION ITU-R BS.705-1* HF transmitting and receiving antennas characteristics and diagrams** (1990-1995) The ITU Radiocommunication Assembly, considering a) that Resolution ITU-R 31 decided to issue a separately published Recommendation containing a revised and complemented set of HF broadcasting antenna diagrams together with other relevant information; b) that the diagrams published in this Recommendation should be easy to be understood and used by the planning and designing engineers, while retaining all the necessary useful information; c) the experience gained with the previous editions of the ex-CCIR publication “Antenna diagrams”; d) that the characteristics of the HF antennas as contained in Annexes 1 and 2 to this Recommendation have a wide application, further considering e) that the radiation pattern of the receiving antenna should also be taken into account when planning sound broadcasting services in band 7 (HF); f) that up to the present time no receiving antenna radiation pattern has been defined for the above purpose; g) that the receiving environment significantly affects the radiation pattern of receiving antennas; h) that a short vertical whip antenna is most often used for reception of sound broadcasting in band 7 (HF), recommends 1 that the formulae as illustrated by sample diagrams and contained in Appendix 1 to Annex 1 of this Recommendation together with the corresponding computer programs should be used to evaluate the performance of HF transmitting antennas; particularly for planning purposes; 2 that the formula as illustrated by a sample diagram and contained in Part 1 to Annex 2 to this Recommendation should be used to evaluate the performance of the receiving antenna for planning sound broadcasting services in band 7 (HF). -
Taoglas Catalog
Product Catalog 2 Taoglas Products & Services Catalog Wireless communications are positively Our new line of LPWA antennas plays a major role changing the world, and we’re here to in realizing the value of low connectivity cost and help. Our product lineup brings the latest reduced power consumption. innovations in IoT and Transportation antenna solutions. Our Sure GNSS high precision series includes the AQHA.50 and AQHA.11 antennas to support At Taoglas we work hard to develop the next the growing demand for high precision GNSS wave of cutting-edge antenna solutions to add solutions. Our product offering comprises of both to our already market-leading product offering. embedded and external antennas for timing, Inside this catalog, you will find our ever-growing location and RTK applications. product range presented by frequency bands, giving you what you need at your fingertips to Our Antenna Builder and Cable Builder, available build your solution with complete confidence. online makes it easy for our customers to build and customize antenna and cabling solution with Taoglas continues to make significant the promise of product delivery within as little as investments in our production and infrastructure. two days. Our IATF-16949 certification approval is the global standard for quality assurance for the Our range of services continues to support automotive industry. some of the world’s leading IoT brands, helping them to optimize their products to ensure Staying on the cutting-edge of innovation, reliable performance on a global scale with we have developed new Beam Steering IoT endless design solutions including LDS. Utilizing antenna solutions. -
Design and Optimization of Electrically Small Antennas for High Frequency (Hf) Applications
DESIGN AND OPTIMIZATION OF ELECTRICALLY SMALL ANTENNAS FOR HIGH FREQUENCY (HF) APPLICATIONS A DISSERTATION SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI‘I AT MĀNOA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN ELECTRICAL ENGINEERING DECEMBER 2014 By James M. Baker Dissertation Committee: Magdy F. Iskander, Chairperson Zhengqing Yun David Garmire Victor Lubecke John Madey Keywords: Compact HF, Coastal Radar, Electrically Small Antennas Copyright By James M. Baker 2014 ii ABSTRACT This dissertation presents new concepts and design approaches for the development and optimization of electrically small antennas (ESA) suitable for high frequency (HF) radio communications and coastal surface wave radar applications. For many ESA applications, the primary characteristics of interest (and limiting factors) are lowest self- resonant frequency achieved, input impedance, radiation resistance, and maximum bandwidth achieved. The trade-offs between these characteristics must be balanced when reducing antenna size in order to retain acceptable performance. The concept of “inner toploading” is introduced and utilized in traditional and new designs to reduce antenna ka and resonant frequencies without increasing physical size. Two different design approaches for implementing the new concept were pursued and results presented. The first design approach investigated toroidal and helical designs, including combinations of toroidal helical antennas, helical meandering line antennas, and additional designs incorporating toploading and folding to improve performance. The other approach investigated fractal-based designs in two and three dimensions to improve performance, reduce size, and lower resonant frequency. The performance characteristics of fractal geometries were analyzed and compared with non-fractal designs of similar height, total wire length, and ka.