Rf or RF is an abbreviation for Science and technology Radiative forcing , a measure of the change in balance of the energy absorbed and emitted by the Earth s atmosphere Rate of flow , as in Volumetric flow rate Radio frequency RF connector s, a type of electrical connectors designed to work at radio frequencies Random forest , a machine learning algorithm Receptive field , a term used in neuroscience referring to the kinds of stimuli to which a neuron is sensitive Recombinant frequency , a term used in genetics to measure genetic linkage Register file , an array of processor registers in a CPU Retardation factor or retention factor , designated as R sub f sub , a term used in chromatography Reticular formation Rheumatoid factor , a blood test used to diagnose rheumatoid arthritis Ancient Roman units of measurement Length Roman foot , an ancient Roman unit of measurement Rutherfordium , a chemical element Release factor Politics France R publique Fran aise Rhodesian Front , the governing party of Rhodesia under the UDI Russian Federation Sports Range Factor , a baseball statistic Right fielder , a defensive position in baseball Roger Federer , a tennis player Rio Ferdinand Fiction and gaming Rumble Fighter , a multiplayer online fighting game published by OGPPlanet Red Faction , a first person shooter game that was released in 2001 by THQ and Volition RF Online , an online RPG ... Economics Royalty free RF, the NYSE ticker symbol for Regions Financial Corporation Other South Vietnamese ... , a directive in sheet music Mazda F engine RFRF , a Mazda piston engine RF Generation , a video gaming ... , a Japanese radio station in the vicinity of Tokyo JORF RF, the IATA code for Florida West International Airways RF, AEC Regal IV , a 39 seat single deck bus, built for London Transport between 1951 ... Initialisms cs RF de RF eo Rf fa RF fr RF ko RF it RF sw RF ja RF pl RF pt RF ru sr Rf fi Rf sv RF th RF ... more details
orphan date March 2010 An RF probe , sometimes called an RF detector is a simple test device to detect radio frequency oscillation in an electronic circuit . This device will work as a RF rectifier and give a pulsed Direct current DC volt age. ref http www.instructables.com id RF probe Instructables, RF Probe ref Image RF probe.gif References reflist The Encyclopedia of Electronic Circuits by Rudolf F. Graf, William Sheets. Published by McGraw Hill Professional, 1996 ISBN 0 07 011275 4, 9780070112759 External links http www.indianapolis.net QRPp I KA8MAV RF Probe.html KA8MAV RF Probe http groups.google.ca groups?selm 31E834A8.2111 40gv.net Post to sci.electronics.design Category Radio electronics Category Electronics terms Category Electronic circuits Category Electronic test equipment electronics stub ... more details
Unreferenced date December 2009 Orphan date February 2009 An RF unit , also known as an RF Modulator is a device used to connect video devices, such as DVD player s and video game console s to televisions that do not have RCA jack connections. It converts the audio & video signal to a Radio frequency RF signal that can be tuned by a TV tuner , usually on channel 3 or 4 with mono audio. RF modulators provide the overall poorest quality when compared to RCA Jacks, S Video or Digital Visual Interface DVI connections. DEFAULTSORT Rf Unit Category Coaxial connectors Category Video game hardware ... more details
Multiple issues orphan March 2012 wikify April 2011 context April 2011 An RF Module is a usually small ... frequencies. RF Modules are widely used in consumer application such as garage door openers, wireless ... in commercially available RF modules, including 433.92MHz, 315MHz, 868MHz and 915MHz. Deleted RF modules are normally divided into three groups, RF transmitter module, RF receiver module and RF transceiver module. Deleted image removed File RF transmitter module solidremote.jpg thumb 250px this is a typical photo of 433MHz RF transmitter module. Deleted Transmitter module is an electronic component ... compared to remote controls using infrared technology. And RF modules are widely used in garage door ... receiver and Super regenerative receiver There are two types of RF receiver modules superheterodyne .... RF Signal Modulation Deleted image removed File RF receiver module solidremote.jpg thumb 250px this is a typical photo of adjustable frequency RF receiver module with fixed code decoder IC PT2272 built in. There are three types of signal modulation methods commonly used in RF transmitter & receiver ... Users of RF module may use any soft or hard wire likes Drawbars antenna as antenna. The frequency ... an external antenna to an RF Module, superior performance can be achieved by selecting an antenna ... length, while for a 433.92 MHz, use a 18 cm antenna. Main factors affecting RF module performance As with any other radio frequency device, the performance of an RF Module will depend ... transmit power will make the system more prone to interference with other RF devices, and may ... potentially cause malfunction due to interference with other RF devices. The performance of the overall ... remote distance, but also prone to cause interference with other RF devices. the receiver ... to cause malfunction due to interference with other RF devices. the antenna using for example, a stretched ... system radio tags reading RF contactless smart cards wireless data terminals wireless fire protection ... more details
unreferenced date March 2012 In the context of mobile radio communication systems, RF Planning is the process of assigning frequencies, transmitter locations and parameters of a wireless communications system to provide sufficient coverage and capacity for the services required. The RF plan of a cellular communication system has two objectives coverage and capacity. Coverage relates to the geographical footprint within the system that has sufficient RF signal strength to provide for a call data session. Capacity relates to the capability of the system to sustain a given number of subscribers. Capacity and coverage are interrelated. To improve coverage, capacity has to be sacrificed, while to improve capacity, coverage will have to be sacrificed The RF Planning process consists of four major stages. Phase 1 Initial Radio Link Budgeting The first level of the RF planning process is a budgetary level. It uses the RF Link Budget along with a statistical propagation model e.g. Hata, COST 231 Hata or Erceg Greenstein to approximate the coverage area of the planned sites and to eventually determine how many sites are required for the particular RF communication system. The statistical propagation model does not include terrain effects and has a slope and intercept value for each type of environment ... of outputs produced at this stage Estimated Number of Sites Phase 2 Detailed RF Propagation Modelling The second level of the RF Planning process relies a more detailed propagation model. Automatic planning ..., its use, in conjunction with the RF link budget, produces a more accurate determination of the number ... Throughput Phase 3 Fine Tuning and Optimisation The third phase of the RF planning process incorporates further detail into the RF plan. This stage includes items such as collecting drive data ... phase of the RF planning process involves continuous optimisation of the RF plan to accommodate for changes ... lte radio link budgeting and rf planning lte rf planning An Introduction to LTE RF Planning ... more details
Refimprove date May 2008 Infobox Occupation name RF engineering image caption official names RF engineer Outside broadcasting Outside Broadcast RF Engineer Details type profession activity sector competencies Technical knowledge, Management skills, Professionalism formation Mathematics , Physics , Electronics , Information technology employment field Radio , Television , Military related occupation Technology Technologist , Broadcast engineer , Engineering technician , Technical Operator average salary Merge from Radio electronics date August 2010 Radio frequency RF engineering is a subset of electrical engineering that deals with devices that are designed to operate in the Radio Frequency spectrum. These devices operate within the range of about 3 Hertz kHz up to 300 Hertz GHz . RF engineering is incorporated into almost everything that transmits or receives a radio wave , which includes, but is not limited to, Mobile Phones , Radios , WiFi , and walkie talkies. RF engineering is a highly specialized field. To produce quality results, an in depth knowledge of mathematics , physics , general electronics theory as well as specialized training in propagation and microstrip design may be required. Even with this, the initial design of an RF circuit usually bears very little resemblance to the final physical circuit produced, as revisions to the design are often required to achieve intended results. Duties RF engineers are specialists in their respective field and can take on many different roles, such as design, installation, and maintenance. RF engineers require many years of extensive experience in the area of study. This type of engineer has experience with transmission systems, device design, and placement of antennas for optimum performance. An RF Engineer at a broadcast ... STL Transmitter studio link TSL links, and more. In addition, an RF design engineer must be able to understand .... Many notable individuals have contributed to the advancement of RF engineering theory and design ... more details
Image ExampleImageMini RF.png thumb right An example Mini RF total radar backscatter image taken in the 12.6 cm band. It shows a fresh lunar impact crater with an ejecta blanket surrounding it. The Miniature Radio Frequency instrument Mini RF is a synthetic aperture radar SAR instrument on the Lunar Reconnaissance Orbiter LRO , which is currently in orbit around the Moon . It has a resolution of 30 m pixel and two wavelength bands, a primary band at 12.6 cm and a secondary band at 4.2 cm. ref name NozetteEtAl10 cite journal title The Lunar Reconnaissance Orbiter Miniature Radio Frequency Mini RF Technology Demonstration last1 Nozette first1 Stewart last2 Spudis first2 Paul last3 Bussey first3 Ben last4 Jensen first4 Robert last5 Raney first5 Keith coauthors et al. journal Space Science Reviews date January 2010 volume 150 pages 285 302 bibcode 2010SSRv..150..285N doi 10.1007 s11214 009 9607 5 ref ref name NeishEtAl11 cite journal title The nature of lunar volatiles as revealed by Mini RF observations of the LCROSS impact site date January, 2011 journal Journal of Geophysical Research authors C. D. Neish, D. B. J. Bussey, P. Spudis, W. Marshall, B. J. Thomson, et al. ref The original principal investigator of Mini RF, Stewart Nozette , was arrested for espionage, and the current principal investigator is Ben Bussey of the Applied Physics Laboratory , where Mini RF was built. Previous synthetic aperture radar SAR instruments, such as the radar on the Magellan spacecraft ... of cheap, lightweight SAR technology, the Mini RF instrument was designed in response to these concerns. Because it was a technology demonstration, Mini RF is sometimes not included in lists of Lunar ... Crater, Mini RF did not detect water ice at the LCROSS impact site. ref name NeishEtAl11 In January, 2011, after completion of Mini RF s primary mission objectives, NASA announced that Mini RF had ... External links http www.nasa.gov mission pages Mini RF news radar tandem searches.html Nasa Radar ... more details
frequency electromechanical microelectromechanical system RF Microelectromechanical systems MEMS acronym refers to electronic component s of which moving sub millimeter sized parts provide RF functionality. RF functionality can be implemented using a variety of RF technologies. Besides RF MEMS ... ferrite , ferroelectric , silicon based semiconductor CMOS RF CMOS , SiC and SiGe , and vacuum tube technology are available to the RF designer. Each of the RF technologies offers a distinct trade off .... Components There are various types of RF MEMS components, such as CMOS integrable RF MEMS resonators ... form factor and low phase noise , RF MEMS Electronic tuner tunable inductor s, and RF MEMS ... discussed in this article are based on RF MEMS switches, switched capacitors and varactors. These components ... configuration , and PIN diode PIN diodes. RF MEMS switches, switched capacitors and varactors are classified ... beam , or by contact interface capacitive , Ohmic contact ohmic . Electrostatically actuated RF MEMS ... or Wafer level Packaging wafer level packaging anodic or glass frit wafer bonding . RF MEMS switches ..., 1994 ref ref C. L. Goldsmith, Z. Yao, S. Eshelman, and D. Denniston Performance of Low Loss RF MEMS ..., M. Kim, and J. F. DeNatale A Ka band 3 Bit RF MEMS True Time Delay Network, IEEE Trans. Microw. Theory Tech., vol. 51, no. 1, pp. 305 308, Jan. 2003 ref A capacitive fixed fixed beam RF MEMS switch ... band 77 GHz and 94 GHz RF MEMS components. An ohmic cantilever RF MEMS switch, as shown in Fig ... band components. File RF MEMS.png thumb 640px Fig. 1 a A capacitive fixed fixed beam RF MEMS switch, connected in shunt to a CPW line. b An ohmic cantilever RF MEMS switch, connected in series to a microstrip ... and the mass allows for hand calculation of the switching time. From an RF perspective, the components ... is between 20 and 50 in the X , Ku band Ku and Ka band. RF MEMS switched capacitors are capacitive fixed fixed beam switches with a low capacitance ratio. RF MEMS varactors are capacitive fixed fixed ... more details
frequency. RF modulators produce a relatively poor picture, as image quality is lost during ... are no longer included as standard equipment, and RF modulators are now largely a third party product, purchased primarily to run newer equipment such as DVD player s on old televisions. An RF ... composite AV source, and generates a broadcast RF signal that can be fed into a television s aerial coaxial connector. Multi channel RF modulators are commonly used in home audio video distribution. These devices have multiple audio and video inputs and one RF output. Audio video outputs from source .... The modulator is then programmed to broadcast the signals on a certain frequency. That RF ... video signal of the source device is accessed. RF modulation can become difficult in a CATV system ... Internal RF modulators are commonly found in VCR s, in older video game consoles such as the Atari ... for video game systems that did not have internal RF modulators to provide external units that connected ... an RF signal must in general be certified by regulatory authorities in the US, the FCC and thus by having an external RF modulator, only the modulator itself needed to be certified, rather than the entire ... a signal, and only the device signal is sent onward, to reduce interference. In North America, RF modulators ... not intended for Cable television professional use lack vestigal sideband filtering. Audio RF modulators ... Video hardware ca Unitat de RF de HF Modulator es Unidad RF nl HF modulator pt Modulador de radiofrequ ncia fi RF modulaattori ... more details
Notability date November 2010 R.F. Tapsell Robert Frederick Tapsell was an English author born in 1936, ref Library Thing http www.librarything.com author tapsellrf R.F. Tapsell , Library Thing , accessed November 8, 2010. ref who wrote three historical novels and was the editor of a single non fiction book on royal dynasties. Tapsell worked in military intelligence with the Royal Air Force RAF , specializing in Eastern Europe . ref Holmes, Morgan http www.rehupa.com ?p 768 Year of the Horsetails , The Robert E. Howard United Press Association , March 22, 2009, accessed November 8, 2010. ref After leaving the RAF, he studied at the School of Slavonic and East European Studies at London University, graduating with a BA Hons in History. R.F. Tapsell later moved into University administration, working at several British universities before emigrating to Australia in 1974. He returned to the United Kingdom in 1982 and died in April 1984. He is survived by his widow and two sons. Bibliography Monarchs, Rulers, Dynasties and Kingdoms of the World An Encyclopaedic Guide to More Than 13,000 Rulers and 1,000 Dynasties from 3000 BC to the 20th Century 1983 ISBN 978 0500273371 Shadow of Wings 1972 ISBN 0 09 109420 8 The Unholy Pilgrim 1968 ISBN 0090871405 The Year of the Horsetails 1967 ASIN B000OLZQAY External links http www.amazon.com R. F Tapsell e B001KIJY6C Amazon.com R.F. Tapsell page References Reflist Persondata Metadata see Wikipedia Persondata . name Tapsell, R.F. alternative names short description date of birth 1936 place of birth date of death 1984 place of death DEFAULTSORT Tapsell, R.F. Category 1936 births Category 1984 deaths Category English novelists Category English writers Category Writers of historical fiction set in Antiquity ... more details
Image N Connector.jpg thumb Male Type N RF connector. A coaxial RF connector is an electrical connector designed to work at radio frequencies in the multi megahertz range. RF connectors are typically used with coaxial cable s and are designed to maintain the shielding that the coaxial design offers. Better models also minimize the change in transmission line Characteristic impedance impedance at the connection. Mechanically, they provide a fastening mechanism Screw thread thread , Bayonet mount bayonet , braces, push pull and Spring device springs for a low ohmic electric contact while sparing the gold surface, thus allowing above 1000 reconnects and reducing the zero insertion force insertion force . Research activity in the area of radio frequency RF circuit design has surged in the last decade When date December 2011 in direct response to the enormous market demand for inexpensive, high data rate wireless transceivers. ref http www.pasternack.com pdf catalog ConnectorIdentifier.pdf, Pasternack, Inc. ref Types Image Miniquick.jpg thumb The coaxial connector Miniquick Image N Right Angle ... threaded base for durability in wind. SC RF connector SC connector , screw version of C connector SMA ... SMB connector SMC connector SMP connector Precision types APC 7 connector Flange connectors EIA RF Connectors series of RF flange connectors Quick lock connectors QMA and QN connector QLS connector ... The following audio and video connector s are sometimes used for RF, but are not generally considered to be RF connectors DIN connector not to be confused with the 7 16 DIN connector RCA connector Radio ... References reflist External links commonscat RF connectors http nocat.net connectors.html Microwave connector reference http www.wa1mba.org rfconn.htm RF connectors for upper frequencies http ece ... dead link date February 2012 RF Connectors Navbox state uncollapsed Analogvideo Electronic components ... es Conector de RF et RF konnektor he RF ja RF ru ... more details
Infobox camera camera name Konica Hexar RF image name Hexar rf 1 weba.jpg type 135 film 35 mm rangefinder ... 2.5frame s in continuous mode dimensions 139.5x80x35mm, 560g w o batteries The Konica Hexar RF is a 135 ... October 1999. ref name cq hexar rf cite web url http www.cameraquest.com konicam.htm title CameraQuest Konica Hexar RF year 2006 accessdate 2007 09 03 work Stephen Gandy ref and subsequently discontinued apparently without official notice some time before the end of 2003. ref name cq hexar rf The camera ... RF has a combined rangefinder viewfinder modeled on that of Leica cameras, a similar body shape and size ... Hexar RF accepts Photographic lens lenses designed for the Bayonet Konica KM mount a copy of the Leica M mount . Because of this, the Hexar RF can mount and Focus optics focus lenses designed for the Leica ... and discussion about whether the Bayonet Konica KM mount of the Hexar RF was, in fact, fully ... title Leica FAQ Are leica M lenses compatible with the Konica Hexar RF year 2006 accessdate ... on Hexar RF cameras. Konica made no comment on the issue, and continued to refer to their lens mount by their own name, with no reference to Leica. ref name cq hexar rf Other testers found no problems ... accessdate 2007 09 03 work Dante Stella ref Viewfinder Rangefinder Image Hexar rf 2 web.jpg thumb right 280px Hexar RF with 35mm lens, showing viewfinder on right and second window for split image rangefinder The Konica Hexar RF camera uses a viewfinder combined with a Photographic lens lens coupled ... by the mounted lens. The .60x magnification used in the Hexar RF viewfinder allows for all framelines ... The Konica Hexar RF is similar in form factor to Leica M mount camera cameras , being slightly larger ... of the Hexar RF appears to be identical to that used by the Contax G2 , with different top and bottom ... RF appears in some ways similar to the earlier auto focus Konica Hexar camera, it seems to share few ... plate has the cover for the batteries and a tripod socket. Film transport The Konica Hexar RF has ... more details
Infobox Website name RF Generation logo Image RF Generation logo.png 180px FAIR USE of Image RF Generation logo.png see image description page at http en.wikipedia.org wiki Image RF Generation logo.png for rationale screenshot Deleted image removed Image RF Generation home.png 299px FAIR USE of Image RF Generation home.png see image description page at http en.wikipedia.org wiki Image RF Generation home.png for rationale caption url http www.rfgeneration.com rfgeneration.com commercial No type Gaming language English registration Optional owner author Laurel Settee, Michael Collins, Mark Hartholt, Eddie Herrmann, Mike Leon, and Rick Kuethe ref RF Generation About page http www.rfgeneration.com PHP about.php ref launch date June 8, 2004 current status revenue slogan Put it on channel 3 RF Generation is a video gaming website that collects information, images and statistics related to video game s and video game hardware both past and present. Games and hardware developed in every region around the world are featured for the public to view, track and search for information. The website s purpose is to allow registered members to display their collection, trade, buy and sell with other members and ask for advice and expertise from highly knowledgeable staff, collectors and gamers from around the world. Registration is free and so are all of the services and features the site has to offer and is available to anyone with an interest in gaming. Currently RF Generation has over 190 different sections in the database covering games and hardware ranging everything from the Magnavox Odyssey from 1972 to Nintendo s Wii and other new video game systems currently on the market as well ..., video game resources and affiliates as well as banners for use in both RF Generation s forum ... gaming related. History RF Generation was founded on April 28, 2004, by Michael Collins, Mark ... RF Generation http www.myspace.com RFGeneration RF Generation on MySpace Category ... more details
RF Switch or Microwave Switch An RF Radio Frequency and microwave switch is a device to route high frequency signal through transmission paths. RF and microwave switches are used extensively in microwave test systems for signal routing between instruments and devices under test DUT . Incorporating a switch into a switch matrix system enables you to route signals from multiple instruments to single or multiple DUTs. This allows multiple tests to be performed with the same setup, eliminating the need for frequent connects and disconnects. The entire testing process can be automated, increasing the throughput in high volume production environments. Similar to electrical switch electrical switches , RF and microwave switches come in different configurations providing the flexibility to create complex matrices and automated test systems for many different applications. Below is a list of typical switch configurations and usage Single pole double throw SPDT switches route signals from one input ... Switch Application.png thumb Typical application of a 4 port bypass switch RF & Microwave Switch Technologies RF and microwave switches can be categorized into two equally mainstream and essential ... life 5 million cycles infinite ESD immunity high low Sensitive to vibration RF power overstress Critical parameters for RF and microwave switches Frequency range RF and microwave applications range ... of the RF signal, settling time is often highlighted in solid state switch performance where the need ... switching, cold switching, average power and peak power. Hot switching occurs when RF microwave power ... conduct RF power when the diode is reverse biased and reflect RF power when forward biased. Video leakage Video leakage refers to the spurious signals present at the RF ports of the switch when it is switched without an RF signal present. These signals arise from the waveforms generated by the switch ... pdf 5989 6085EN.pdf doi Citation last Agilent title Understanding RF Microwave Solid State Switches ... more details
Use British English date October 2011 Use dmy dates date October 2011 RF Engines Limited of Newport, Isle of Wight , UK was founded in 1999. RF Engines RFEL develops and patents as appropriate products based on high performance, state of the art, digital signal processing techniques that enable fast moving events or fleeting, hopping signals occurring in the radio spectrum to be identified and acquired in real time for subsequent analysis. These IP Intellectual Property cores are then incorporated into an increasing number of RFEL s own products as well as their customers products by implementing them into FPGAs field programmable gate array s mainly from Xilinx and Altera . RFEL s products have a variety of applications, including in the design of efficient wireless communication satellite and terrestrial networks, test and measurement instrumentation, homeland security surveillance systems, bespoke wideband receivers transceivers and in systems to detect signals from fast moving missiles or other military threats. Privately owned, it has been profitable for several years and has been steadily growing year on year both in revenue terms and head count, employing over 20 highly qualified ... Ministry of Defence ref http www.electronicsweekly.com Articles 2002 12 04 27612 rf engines wins government funding for dsp design work.htm RF Engines wins government funding for DSP design work 12 ... ref http www.mil embedded.com news Contracts 983 Rheinmetall Defense Contracts RF Engines for an FPGA ... and LIG Nex1 Korea ref http www.dsp fpga.com news Industry News 12867 RF Engines supply advanced ... 2004 11 23 31641 rf engines teams with swiss firm.htm RF Engines teams with Swiss firm 23 November ... designs. Awards Smart award in 2002 http www.electronicsweekly.com Articles 2002 02 20 24210 rf engines ... http www.electronicsweekly.com Articles 2009 04 21 45922 rf engines wins a queens award for innovation.htm References reflist colwidth 30em External links http www.rfel.com RF Engines home page ... more details
, RF Online revolves around PvP Player vs Player . Only the racial headquarters, and the settlement ... DEFAULTSORT Rf Online Category 2005 video games Category Codemasters games Category Fictional ... in South Korea Category Windows games eo RF Online fr Rising Force Online id Rising Force Online ja RF online pt Rising Force Online ru RF Online ... more details
7380 1981 RF is a asteroid belt Main Belt minor planet . It was discovered by Norman G. Thomas at the Anderson Mesa Lowell Observatory south of Flagstaff, Arizona Flagstaff , Arizona , on September 3, 1981. See also List of minor planets 7001&ndash 8000 External links http ssd.jpl.nasa.gov sbdb.cgi?sstr 7380 JPL Small Body Database Browser Minor planets navigator 7379 Naoyaimae 7381 Mamontov Small Solar System bodies DEFAULTSORT 1981 RF Category Astronomical objects discovered in 1981 Category Main Belt asteroids Beltasteroid stub hu 7380 1981 RF uk 7380 1981 RF vi 7380 1981 RF yo 7380 1981 RF ... more details
Unreferenced date September 2007 File Graduate School Project 2870679632 .jpg thumb right An RF power amplifier An RF power amplifier is a type of electronic amplifier used to convert a low power radio frequency Signal electrical engineering signal into a larger signal of significant power, typically for driving the antenna of a transmitter . It is usually optimized to have high efficiency, high output Power P1dB Signal compression compression , good return loss on the input and output, good gain , and optimum heat dissipation. Applications The basic applications of the RF power amplifier include driving to another high power source, driving a transmitting Antenna radio antenna , microwave heating, and exciting resonant cavity structures. Among these applications, driving transmitter antennas is most well known. The transmitter receivers are used not only for voice and data communication but also for weather sensing in the form of a RADAR . Microwave or RF heating is an industrial application which is also benefiting our homes in the form of microwave oven s. Exciting cavity resonator s is quite a research lab and industrial application of an RF source. Particle accelerator s utilize RF sources extensively. Wideband amplifier design Electrical impedance Impedance transformations over large Bandwidth signal processing bandwidth are difficult to realize, thus most wideband amplifier s use 50 output loading. Transistor output power is then limited to math P out le frac V br V k 2 8Z o math math V br math is defined as the breakdown voltage math V k math is defined as the knee voltage and math Z o 50 Omega , math External links http www.mwjournal.com Resources TechLib.asp?HH ID RES 155&CatId 0&alpha Power Amplifier Fundamentals article http www.nxp.com acrobat download various SC19 POWER AMPL DESIGN 1.pdf Power Amplifier Design DEFAULTSORT Rf Power Amplifier Category Electronic amplifiers Category Radio electronics radio comm stub fa RF ... more details
RF microwave CAE CAD is computer aided design CAD using computer technology to aid in the design, modeling, and simulation of an RF or microwave product. It is a visual and symbol based method of communication whose conventions are particular to RF microwave engineering. ref http sss mag.com cad.html ref Scope of design RF and microwave circuit design and simulation software for the electronic design automation EDA marketplace includes but not limited to circuit simulation , analysis, schematic capture , and integrated design environment for synthesis tools which automate the design of HF high frequency circuits from RF to microwave to Extremely high frequency millimeter waves . Physical modeling of stripline and microstrip for transmission line s. A wide range of applications are possible, from analog sub circuit design to RF circuit design for complex wireless communications systems. ref http portal.acm.org citation.cfm?id 1080264 ref Scope of modeling There are a vast number of device or component types which can be simulated in computer aided design software. Generally, the degree of complexity for modeling depends on the software package and the synthesis of off the shelf models and application specific custom models. The component types can be categorized as follows amplifiers , Antenna radio antenna s, attenuator s, Power cable cabling , capacitor s, circulator s, combiner s, coupler s, electrical connector connector s, DC block s, delay lines , detector s, diode s, dividers , Ferrite magnet ferrites , Electronic filter filter s, inductor s, isolator s, limiter s, mixer s, oscillator s, phase shifter s, resistor s, rotary joint s, switch es, transistor s, Terminator electrical terminators , and waveguides . References Computer aided design of RF and microwave circuits and systems , Microwave Theory and Techniques, IEEE Transactions. http www.mwee.com magazine 1999 ... reflist DEFAULTSORT Rf Microwave Cae Cad Category Computer aided design software Category Computer ... more details
10314 1990 RF is an asteroid belt outer main belt minor planet . It was discovered by Henry E. Holt at the Palomar Observatory in San Diego County, California San Diego County , California, on September 14, 1990. ref http ssd.jpl.nasa.gov sbdb.cgi?sstr 10314 JPL Small Body Database Browser ref See also List of minor planets 10001 11000 References reflist beltasteroid stub MinorPlanets Navigator 10313 Vanessa Mae 10315 Brewster Small Solar System bodies DEFAULTSORT 1990 RF Category Astronomical objects discovered in 1990 Category Discoveries by Henry E. Holt Category Main Belt asteroids vi 10314 1990 RF ... more details
85212 1992 RF is a asteroid belt main belt minor planet . It was discovered by Robert H. McNaught at the Siding Spring Observatory in Coonabarabran, New South Wales , Australia, on September 4, 1992. ref http ssd.jpl.nasa.gov sbdb.cgi?sstr 85212 JPL Small Body Database Browser ref See also List of minor planets 85001 86000 References reflist beltasteroid stub MinorPlanets Navigator 85211 1992 PL 85213 1992 RN7 Small Solar System bodies DEFAULTSORT 1992 RF Category Astronomical objects discovered in 1992 Category Discoveries by Robert H. McNaught Category Main Belt asteroids vi 85212 1992 RF ... more details
Expert subject Physics date November 2008 An RF antenna ion source or radio frequency antenna ion source is an internal multi cusp design that can produce a particle beam of about 30 to 40 Ampere mA current. It is used in high energy particle physics and in accelerator laboratories. Previous RF antennas would penetrate the porcelain enamel coating on the antenna section at high RF power. This problem has been corrected in the development stage with a ten layer coating of titanium dioxide , with approximately 1 mm thick coating. With the development of the RF antenna ion source, or non Thermionic emission thermionic ion source, the ion source has an advantage over conventional cold cathode s and hot filament ion sources. The Electrical filament filament continuously burns out over time with a shorter lifespan, requiring venting of the ion source to atmosphere and rebuilding of the ion source. See also Ion source Particle accelerator External links Lawrence Berkley National Laboratory http www ibt.lbl.gov PIS publications RSI 71 1134.pdf Improvement of the lifetime of radio frequency antenna DEFAULTSORT Rf Antenna Ion Source Category Particle physics Category Accelerator physics Accelerator stub ... more details
The Rollei 35 RF 2002 is a version of the Cosina Voigtl nder Bessa 35mm Bessa R2 marketed not by Cosina but instead by Rollei , complete with a Rollei 40mm lens. Like the Bessa R2, the Rollei 35 RF has a Leica M mount and a metal focal plane shutter. Its TTL exposure meter requires batteries, but batteries are not otherwise needed. Shutter speeds range from 1 to 1 2000s and bulb B , with flash sync at 1 125s on hot shoe or PC terminal. The most obvious differences from the R2 are the price much higher and somewhat gaudy appearance more silver, and more prominent branding. Beside this badge engineering, there are other differences. The shutter speed knob and the grip on the body are slightly redesigned and more importantly the framelines are for 40, 50, and 80mm. This camera was so transparently a Cosina, and complete with 40mm lens its price was so high, that it was greeted without much enthusiasm when released. With or without its original lens, it is now 2006 easily found in like new condition for well below its original price. Arguably it remains the best Bessa camera for people who wear glasses and primarily use a 40mm lens. External links http web.archive.org web 20050305012118 www.rollei usa.com compact 35rf.htm Rollei 35 RF as written up by Rollei http www.rangefinderforum.com forums showthread.php?t 664 Rollei 35 RF review at rangefinderforum.com Leica M bodies From Camerapedia Rollei 35 RF Category Leica M mount Category Rangefinder cameras ... more details
Personal RF safety monitors Electromagnetic field dosimeters measure the exposure to electromagnetic ... to as personal radio frequency RF safety monitors . They form part of the personal protective equipment worn by a person working in areas exposed to radio spectrum radiation. A personal RF safety ... Radman unit Most of the scientifically proven RF safety monitors are calibrated to measure the RF exposure as a percentage of the two most common international RF safety guidelines endorsed by the WHO ... Commission ref Personal RF Safety monitors were originally designed for RF Engineer s working in environments where they could be exposed to high levels of RF energy or be working close to a RF ... of a building with transmitting antenna s present. Most international RF safety programs include the training and use of Personal RF safety monitors. ref name RecommendedPractice http ieeexplore.ieee.org ... cases the RF safety monitor comes in a version or mode for the general public. ref name fieldsense ... be exposed to high levels of RF energy or it might be used to indicate the RF level at areas where the general public has access. Specification The specifications of a RF monitor determines the work environment it can be used for. Wideband RF monitors can be used at a broader variety of base station site types than for example a narrowband , cellular RF monitor which is designed only to be used ... of some RF monitors class wikitable Specification Narda Radman ref name narda sts cite web url ... A Operating Instructions Image Scan with RF monitor.jpg thumb 175px Scan for leak in RF feeder Each specific personal RF safety monitor has its own operating instructions. And most of the monitors have ... to warn RF technicians that the antenna is live and that any work on the antennas should be ceased until deactivation is confirmed. The more expensive RF monitors typically also have a data logging functionality that can log the RF exposure of a worker over time. ref name narda sts ref name satimo ... more details
Unreferenced stub auto yes date December 2009 In a radio receiver circuit, the RF front end is a generic term for all the Electrical circuit circuitry between the Antenna radio antenna and the first intermediate frequency IF stage. It consists of all the components in the receiver that process the signal at the original incoming radio frequency RF , before it is converted to a lower intermediate frequency IF . In microwave and satellite receivers it is often called the Low noise block converter low noise block LNB or low noise downconverter LND and is often located at the antenna, so that the signal from the antenna can be transferred to the rest of the receiver at the more easily handled intermediate frequency. For most Superheterodyne receiver super heterodyne architectures, the RF front end consists of An impedance matching circuit to match the input impedance of the receiver with the antenna, so the maximum power is transferred from the antenna A gentle band pass filter BPF to reduce input noise and image frequency response An Amplifier RF amplifier , often called the low noise amplifier LNA . Its primary responsibility is to increase the sensitivity of the receiver by amplifying weak signals without contaminating them with noise, so they are above the noise level in succeeding stages. It must have a very low noise figure NF . The Frequency mixer mixer , which mixes the incoming signal with the signal from a local oscillator LO to convert the signal to the intermediate frequency IF . Market analyst firm Mobile Experts estimates the number of RF Front Ends used in the global cellular device market to be more than 8 billion. ref cite news title Handset RFFEs MMPAs, Envelope Tracking, Antenna Tuning, FEMs, and MIMO first Joe last Madden url http mobile experts.net manuals mexp rffe 12 20toc.pdf publisher Mobile Experts accessdate 2 May 2012 ref DEFAULTSORT Rf Front End Category Radio electronics Radio comm stub references ... more details
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