Antenna Selection Guide Richard Wallace Antenna Radiation Pa
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Application Note AN058
Antenna Selection Guide
Richard Wallace
Antenna Radiation Pattern Bandwidth Reflection Anechoic Chamber Impedance Gain Directivity 868/915
Introduction
addition different antenna types presented, with their pros cons. antenna reference designs available www.ti.com/lpw presented. last section this document contains references additional antenna resources such literature, applicable simulation tools list antenna manufacturer consultants. Correct choice antenna will improve system performance reduce cost.
This application note describes important parameters consider when deciding what kind antenna short range device (SRD) application. Important antenna parameters, different antenna types, design aspects techniques characterizing antennas presented. Radiation pattern, gain, impedance matching, bandwidth, size cost some parameters discussed this document. Antenna theory measurement also covered. practical
Antenna
Chip Antenna
Whip Antenna
Figure Different Antenna Solutions
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Table Contents
KEYWORDS. INTRODUCTION. ABBREVIATIONS. BRIEF ANTENNA THEORY. WAVELENGTH CALCULATIONS DIPOLE FREE SPACE ANTENNA CONSIDERATIONS FRIIS TRANSMISSION EQUATION ANTENNA TYPES ANTENNAS 4.1.1 Antenna Reference Designs 4.1.2 Based CHIP ANTENNAS WHIP ANTENNAS. WIRE ANTENNAS. ANTENNA PARAMETERS RADIATION PATTERN GAIN 5.1.1 Dipole Antennas SIZE, COST PERFORMANCE ANTENNA MEASUREMENTS MAXIMUM POWER TRANSFER (VSWR) BANDWIDTH IMPEDANCE MATCHING 6.2.1 Mounting cable measurements ANTENNA REFERENCE DESIGNS AVAILABLE WWW.TI.COM\LPW. 2.4GHZ ANTENNA REFERENCE DESIGNS 7.1.1 Single Ended Antennas 7.1.2 Differential Antennas.24 ANTENNA REFERENCE DESIGNS 7.2.1 Reference Designs 868/915/955 Antennas.25 ADDITIONAL ANTENNA RESOURCES ANTENNA LITERATURE SIMULATION TOOLS ANTENNA SUPPLIERS CONSULTANTS SUMMARY. REFERENCES. APPENDICES 11.1.1 500MHz Chip Antenna YAGEO.33 11.1.2 916MHz Chip Antennas Rainsun GENERAL INFORMATION 12.1 DOCUMENT HISTORY.
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Abbreviations
Application Note Carrier Wave Demonstration Board Design Note Device Under Test Effective Isotropic Radiated Power Electro Magnetic Evaluation Module Inverted Antenna Intellectual Property Industrial, Scientific, Medical Line Sight Meandered Inverted Antenna Printed Circuit Board Radio Frequency Short Range Device Texas Instruments Time Market Voltage Standing Wave Ratio
EIRP MIFA TVSWR
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Brief Antenna Theory
antenna component reaching maximum distance wireless communication system. purpose antenna provide transmission data electromagnetically free space: Transform electrical signals into electromagnetic waves, propagating into free space (transmit mode) Transform electromagnetic waves into electrical signals (receive mode) Wavelength Calculations Dipole Free Space
same output power, sensitivity antenna gain; reducing frequency factor doubles range (line sight). Lowering operating frequency also means that antenna increases size. When choosing operating frequency radio design, available board space must also accommodate antenna. choice antenna, size available should considered early stage design.
meters 2.99792458E8 m/sec (GHz) Table Wavelength Equation Frequency (cm) 3.05 8.19 8.63 17.3 277.58 (inch) 1.204 3.22 3.39 6.77 109.2 (cm) 12.236 32.76 34.5 69.2 1110.3 (inch) 4.81 12.89 13.59 27.1 437.1
Table Various Wavelengths Several Frequency Ranges Antenna Considerations
There numerous issues consider when selecting antenna: materials antenna placement Multi-path returns between Ground planes wavelength antennas Undesired magnetic fields Mismatch from device antenna Objects that alter disrupt Line Sight (LOS) Antenna gain characteristics Antenna bandwidth efficiency
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Friis Transmission Equation
Friis equation primary math model predicting point point communication links. This very elementary equation been expanded include height antenna above ground difference antennas. formula very accurate once constants have been entered. Please refer [36] further information concerning "Range Measurements Open Field Environment".
Equation Friis Transmission Equation Wavelength Meters Received Power Transmit Power Transmit Antenna Gain Receive Antenna Gain Distance between Antennas Meters Friis equation primary math model predicting point point communication links. This very elementary equation been expanded include height antenna above ground difference antennas.
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Antenna Types
There several antenna types choose from when deciding what kind antenna product. Size, cost performance most important factors when choosing antenna. three most commonly used antenna types short range devices antennas, chip antennas whip antennas with connector. There also antennas that patented Wire antennas. Table shows pros cons these antenna types. Antenna types antenna (non based) Pros cost Good performance Small size high frequencies Standard design antennas widely available that patented protected Small size Short Tsince purchasing antenna solution Good performance Short Tsince purchasing antenna solution Large support from company Short Tsince purchasing antenna solution Very cheap Cons Difficult design small efficient antennas Potentially large size frequencies
Chip antenna
Medium performance Medium cost High cost Difficult many applications High cost compared non-IP antenna. Similar cost Chip antenna Larger variance mechanical positioning which could alter antenna performance
Whip antenna
antenna based)
Wire antenna
Table Pros Cons Different Antenna Solutions also common divide antennas into single ended antennas differential antennas. Single ended antennas also called unbalanced antennas, while differential antennas often called balanced antennas. Single ended antennas signal which referred ground characteristic impedance these antennas usually ohms. Most measurement equipments also referenced ohms. Therefore, easy measure characteristic antenna with such equipment. However many IC's have differential ports transformation network required single ended antenna with these IC's. Such network called balun since transforms signal from balanced unbalanced configuration. Figure shows single ended antenna differential antenna. figure shows differential antenna connected directly pins balun needed single ended antenna.
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Single Ended Antenna
Differential Antenna
Figure Single Ended Differential Antenna take dipole techniques like meandering decrease overall board size. Here feed line (smaller line provides impedance change. first line intersects main antenna trace impedance changes root Zt1. smaller trace width between feed line increases input impedance root Zt2. larger line right connects ground plane other half antenna. There several fine tuning done that discussed increase efficiency other order specs. antennas presented this document mainly intended license free 2.4835 band, 863-870 band Europe, 902-928 band Japanese band MHz. European band usually referred "868 band" band commonly designated "915 band". often possible achieve good performance with same antenna both European bands tuning antenna length changing values matching components. Such antennas called "868/915 antennas" this document.
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Antennas
ambition provide excellent design application notes design-in process will easier quicker. With designs, antenna design critical stage able achieve best possible link budget specific application. previously mentioned 3.2, there many considerations consider when choosing type antenna. antenna application notes updated regularly improved with designs. antenna designs that released free charge used directly final application design. addition these free antenna designs, also have specific antennas designs that based. antenna company usually specific design profile such directivity compact design example. antenna basic form, PIFA, patch, spiral generally free from patent infringement because these well known designs that have been around many years. When antenna adapted from "standard format"; then antennas more than likely protected through patents. important keep this mind when developing antenna. Many antenna patents collide with each other which company original valid long discussion. advisable keep standard text book antenna designs when developing antenna avoid legal discussions. 4.1.1 Antenna Reference Designs
Designing antenna straight forward usually simulation tool must used obtain acceptable solution. addition deriving optimum design, configuring such tool perform accurate simulations also difficult time consuming. therefore recommended make exact copy reference designs available www.ti.com/lpw, available board space permits such solution. section description available reference designs. application requires special type antenna none available reference designs fits application, could advantageous contact antenna consultant look other commercially available solutions. Table lists companies that offer such services. 4.1.2 Based
There many antenna design companies that sell their antenna design competence through Since there silicon firmware involved; only antenna companies protect their antenna design through patents. Purchasing chip antenna purchasing antenna design similar since there external cost antenna design. Figure shows board with CC2430 quarter wave slot antenna from Pinyon. antennas from Pinyon specifically designed directional operation. Applications environments such corridor coverage, metering surveillance, maximum range distance between fixed devices ideal applications Pinyon type directivity antenna. advantage using directional antenna power reduced higher gain antenna between devices given distance that current consumption reduced. Another advantage that antenna gain utilized achieve greater range distance between devices. However, disadvantage using directional antennas that positioning transmitter receiver unit must known detail. this information known then best standard omni-directional antenna design such described DN007 [4].
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important state that antenna gain similar amplifier gain where there more power generated. Antenna gain just measure antenna directivity antenna only radiated power that entered into antenna. alternative Pinyon antenna standard patch antenna which will also give directivity with cost attached. patch antenna mainly radiates just direction (one main lobe) whereas Pinyon antenna main lobes, similar figure eight, seen Figure
Figure CC2430 Board with Pinyon Quarter Wave Antenna
Fractus also antenna company that uses. Fractus concept design very compact antennas fractal pattern. fractal pattern laid that current flow antenna structure will oppose each other layout size kept minimum. Fractus also sells their antenna chip antenna component. Figure shows selection standard chip antennas that available from Fractus covering GHz, bands.
Figure Standard Chip Antennas Available from Fractus. Chip Antennas
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available board space antenna limited chip antenna could good solution. This antenna type allows small size solutions even frequencies below GHz. trade compared antennas that this solution will mounting cost. typical cost chip antenna between $0.10 $1.00. Even manufacturers chip antennas state that antenna matched ohms certain frequency band, often required additional matching components obtain proper performance. performance numbers recommended matching given data sheets often based measurements done with test board. dimensions this test board usually documented data sheet. important aware that performance required matching might change chip antenna implemented with different size shape ground plane. Whip Antennas
good performance most important factor size cost critical, external antenna with connector could good solution. These antennas often monopoles have omni-directional radiation pattern. This means that antenna approximately same performance directions plane. whip antenna should mounted normally ground plane obtain best performance. Whip antennas typically more expensive than chip antennas, will also require connector board that also increases cost. Notice that some cases special types connectors must used comply with regulations. more information about regulations please Application Note Application Note [2]. Wire Antennas
applications that operate lower bands such MHz; antenna quite large, refer Table Even when earth plane utilized half antenna design; overall size large difficult onto PCB. What done this frequency range which practical cheap; wire used antenna wire formed around mechanical housing application. pros such solution price good performance obtained. cons variations positioning antenna mechanical housing will have controlled that antenna will vary much during volume production.
Antenna Parameters
There several parameters that should considered when choosing antenna wireless device. Some most important things consider radiation varies different directions around antenna, efficient antenna bandwidth which antenna desired performance antenna matching maximum power transfer. Sections give explanation these properties defined they should evaluated. Since antennas require some space PCB, choice antenna often trade between cost, size performance. This will discussed further section 5.2.
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Radiation Pattern Gain
Antenna specs from majority suppliers will reference their designs ideal Isotropic antenna. This model where antenna perfect sphere isolated from external influences. Most measurements power done units where refers condition isotropic antenna. Power measurements theoretical isotropic antenna dBi. Monopole Dipole Antenna Power related isotropic antenna relationship 2.14 dBi. radiation pattern graphical representation radiation properties antenna function space. i.e. antenna's pattern describes antenna radiates energy into space receives energy). common, however, describe this pattern with planar patterns, called principal plane patterns. These principal plane patterns obtained making slices through pattern through maximum value pattern direct measurement. these principal plane patterns that commonly referred antenna patterns. Principal plane patterns even antenna patterns, will frequently encounter terms azimuth plane pattern elevation plane pattern. term azimuth commonly found reference horizontal whereas term elevation commonly refers "the vertical". When used describe antenna patterns, these terms assume that antenna mounted measured) orientation which will used. azimuth plane pattern measured when measurement made traversing entire plane around antenna under test. elevation plane then plane orthogonal plane, plane deg). elevation plane pattern made traversing entire plane around antenna under test. antenna patterns (azimuth elevation plane patterns) frequently shown plots polar coordinates. azimuth plane pattern formed slicing through pattern horizontal plane, plane this case. Notice that azimuth plane pattern directional, antenna does radiate energy equally directions azimuth plane. elevation plane pattern formed slicing pattern through orthogonal plane (either plane plane). gain antenna pattern shown dBi; refer DN027 further information.
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Figure Radiation Pattern from Directional Antenna also important able relate different directions radiation pattern plot antenna. Radiation pattern typically measured three orthogonal planes, x-y, y-z. also possible perform full pattern measurements, this usually done, since time consuming requires expensive equipment. Another defining these three planes using spherical coordinate system. planes will then typically defined 90°, 90°. Figure shows relate spherical notation three planes. information given relate directions radiation pattern plot positioning antenna, direction angles increase towards plane. plane, direction angles increase towards plane, direction angles increase towards
Figure Spherical Coordinate System
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5.1.1 Dipole Antennas dipole antenna most commonly refers half-wavelength (/2) dipole. antenna constructed conductive elements whose combined length about half wavelength intended frequency operation. This simple antenna that radiates energy toward horizon (perpendicular antenna). resulting pattern looks like donut with antenna sitting hole radiating energy outward. strongest energy radiated outward, perpendicular antenna plane. Given these antenna patterns, that dipole antenna should mounted that vertically oriented with respect floor ground. This results maximum amount energy radiating into intended coverage area. null middle pattern will point down. concerned with antenna size antenna further reduced each length dipole wavelength. Then radiator folded turned into ground plane. Figure shows radiation from antenna Figure varies different directions plane PCB. Several parameters important know when interpreting such plot. Some these parameters stated lower left portion Figure addition information shown plot Figure important know relate radiation pattern positioning antenna.
Figure Radiation Pattern gain reference level usually referred isotropic radiating antenna which ideal antenna that same level radiation directions. When such antenna used reference, gain given specified Effective Isotropic Radiated Power (EIRP). outer circle Figure corresponds dBi. dB/div" notation lower left Figure means that each inner circles emission level reduced This means that compared isotropic antenna antenna Figure will have higher radiation direction lower radiation 180° direction.
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Prad
Equation Definition Gain Gain defined ratio maximum average radiation intensity multiplied efficiency antenna, Equation Ohmic losses antenna element reflections feed point antenna determine efficiency. ratio maximum average radiation intensities defined directivity (D). High gain does automatically mean that antenna good performance. Typically system with mobile units desirable have omni-directional radiation pattern such that performance will approximately same regardless which direction units pointed relative each other. application where both receiver transmitter have fixed positions, high gain could desirable. units could placed such that direction maximum gain pointed toward each other, this will result optimum performance with that antenna. Polarization describes direction electric field. electromagnetic waves propagating free space have electric magnetic fields perpendicular direction propagation. Usually, when considering polarization, electric field vector described magnetic field ignored since perpendicular electric field proportional receiving transmitting antenna should have same polarization obtain optimum performance. Most antennas application will practice produce field with polarization more than direction. addition reflections will change polarization electric field. Polarization therefore critical indoor equipment, which experiences lots reflections, equipment operating outside with Line Sight (LOS). Some antennas produce electrical field with determined direction, therefore also important know what kind polarization that used when measuring radiation pattern. also important state which frequency measurement done Generally radiation pattern does change rapidly across frequency. Thus usual measure radiation pattern middle frequency band which antenna going used. narrowband antennas relative level could change slightly within desired frequency band, shape radiation pattern would remain basically same. make accurate measurement radiation pattern, important able measure only direct wave from avoid reflecting waves affecting result. therefore common perform such measurements anechoic chamber. Another requirement that measured signal must plane wave field antenna. field distance (Rf) determined wavelength largest dimension antenna, Equation Since size anechoic chambers limited, common measure large frequency antennas outdoor ranges.
Equation Field Distance size shape ground plane will affect radiation pattern. Figure shows example ground plane affects radiation pattern. radiation pattern upper left corner measured with small antenna board plugged SmartRF04EB, while pattern upper right corner Figure measured with antenna board only connected battery. SmartRF04EB solid ground plane. plugging antenna board into this, effective ground plane seen antenna increased. change size shape ground plane changes gain from -1.2 dBi. Since many applications mobile, always peak gain that most interesting. average radiation plane gives more information about total radiated energy commonly stated when antenna performance presented.
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CC1100EM Antenna SmartRF04EB CC1100EM Antenna without SmartRF04EB
Vertical Polarization, plane dBm,
dB/div Lev:
Vertical Polarization, plane dBm,
dB/div Lev: -1.2
Figure Influence Shape Size Ground Plane Radiation Pattern
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Size, Cost Performance
ideal antenna infinitely small, zero cost excellent performance. real life this possible. Therefore compromise between these parameters needs found. Reducing operating frequency factor doubles range. Thus reasons choosing operate frequency when designing application often need long range. However, most antennas need larger frequencies order achieve good performance. Thus some cases where available board space limited, small efficient high frequency antenna could give same better range than small inefficient frequency antenna. chip antenna good alternative when seeking small antenna solution. Especially frequencies below chip antenna will give much smaller solution compared traditional antenna. main draw backs with chip antennas increased cost often narrow band performance.
Figure Layout Comparison Antenna Chip Antenna Figure shows layout antenna chip antenna. required space antenna solutions indicated with squares. seen from picture, chip antenna consumes much less board space than antenna. radiation efficiency these antenna solutions shown Figure graph clearly shows that chip antenna narrower bandwidth than antenna, even though both antennas have same efficiency middle band. using meandering layout techniques antenna, total size reduced, refer Figure
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Figure Comparison Antenna Chip Antenna
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Antenna Measurements
Maximum Power Transfer (VSWR)
Moritz Jacobi's maximum power theory states that maximum power transfer happens when source resistance equals load resistance. impedances mis-matched, part transmitted signal reflected back into source which Voltage Standing Wave Ratio (VSWR); ratio reflected waveform transmitted waveform. With antenna design, VSWR measure well input impedance antenna matches characteristic impedance output from network.
Table VSWR Chart Bandwidth Impedance Matching
There main ways measuring bandwidth antenna. Measuring radiated power when stepping carrier across frequency band interest measuring reflection feed point antenna with network analyzer. Figure shows measurement radiated power from antenna. results show that antenna approximately variation output power across frequency band radiation center this band. This measurement done with radio stepping continuous wave (CW) from GHz. Such measurements should performed anechoic chamber obtain correct absolute level. This kind measurement however also very useful even anechoic chamber available. Performing such measurement ordinary environment will give relative result, which shows whether antenna optimum performance middle desired frequency band. performance antenna connected spectrum analyzer will affect result. Thus important that this antenna approximately same performance across frequency band being used. This will ensure that result gives correct view relative change performance across measured frequency band.
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Figure Bandwidth Antenna. Another method characterize bandwidth measure reflected power feed point antenna. disconnecting antenna connecting coax cable feed point antenna, such measurements could performed with network analyzer. bandwidth antenna typically defined frequency range which reflection lower than VSWR less than refer Table This equal frequency range where less than available power reflected antenna. More information about reflection measurements found Design Note [10]. Figure shows plots from three reflection measurements performed antenna intended remote control. plot shows reflection when antenna positioned free space with objects vicinity. Encapsulating antenna plastic affects performance lowering resonance frequency. This shown blue graph. holding encapsulated antenna one's hand, performance affected even more. This shows important characterization tuning when antenna placed position environment going used during normal operation.
Figure Reflection Influenced Vicinity Antenna
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6.2.1 Mounting cable measurements
invaluable have semi-rigid cables debugging Solder first shielding onto earth plane then solder connection. Minimize risk ripping tracks when connecting semi-rigid cable. Ready made semi-rigid cables quite expensive re-used again. semi rigid coax cable useful when performing measurements prototypes. outer cable should soldered ground while inner conductor soldered feed line antenna. important that antenna disconnected from rest circuitry when this measurement performed. unshielded part inner conductor should short possible avoid introducing extra inductance when measuring outer should soldered ground close possible cable.
Figure Mounting Semi-Rigid Cable Measure Antenna Characteristics ideal have dedicated boards that specifically used just calibration purposes. Measuring antenna design would require four boards: Open connector air; shield connected Short connector closest GND; shield connected Load: 50ohm calibration, useful 100ohm parallel resistors assembled connection point; shield connected Device Under Test Board. performing these steps then semi-rigid cable also taken care during calibration. just using network analyzer calibration kit; then semi-rigid cables will part measurements. Keep cables constant direction good practice cable ties maintain cables including network analyzer cables fixed position. placement cable affect measurement result, especially there strong currents traveling back forth ground plane.
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Ferrites used reduce influence from currents running outer cable. PCBs which have ground plane with dimensions that fraction wavelength tend have larger currents running ground plane. This could potentially cause more unstable results when trying measure reflection feed pint antennas implemented such PCBs placement ferrite along cable will also affect result. Thus important understand that there certain inaccuracy when performing this kind measurement.
Figure Usage Ferrites during Antenna Measurements
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Antenna Reference Designs Available www.ti.com\lpw
Texas Instruments offers several antenna reference designs. each reference design provides design files documentation that show what kind board antenna tested measured performance. Common these designs that size shape ground plane affects performance antenna. Thus implementing antennas with different shape size ground plane might result slightly different results. important make exact copy dimensions antenna obtain optimum performance. ground plane traces should placed beneath antenna. reference designs presented chapter additional documentation downloaded from www.ti.com\lpw. 2.4GHz Antenna Reference Designs
7.1.1 Single Ended Antennas solutions, provides five different antenna reference designs. Three these single ended antennas matched ohms. These used with products long balun implemented. provides reference designs with balun matched products. smallest antenna solution Meandered Inverted Antenna (MIFA) shown Figure This antenna optimum dongles other implementations with limited board space. antenna performance described Application Note design files showing layout included CC2511 Dongle Reference Design [16].
Figure Meandered Inverted Antenna Inverted Antenna (IFA) shown Figure requires more board space than MIFA, provides more omni-directional radiation pattern than MIFA. This antenna found CC2400DB, CC2420DB CC2430DB reference designs performance documented Design Note [4]. length differs slightly between various boards. reason that length tuned compensate different sizes ground plane different boards.
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Figure Inverted Antenna Together with Fractus [11], Texas Instruments provides application note describing implement chip antenna with radios. Application Note contains implementation recommendations measurement results chip antenna implemented with size dongle. Figure shows required board space this solution.
Figure Chip Antenna from Fractus
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7.1.2 Differential Antennas reduce number external components required balun, possible design differential antenna that matched directly impedance port radio. some cases external components required obtain proper impedance matching filtering. CC2500, CC2510, CC2511 CC2550 have same impedance. This makes possible antenna shown Figure with these products. This antenna design measured performance presented Design Note [5]. only external components needed capacitors ensure compliance with ETSI regulations. Thus compliance external components required proper output power duty cycling used.
Figure CC25xx Folded Dipole CC2400, CC2420 CC243x have slightly different impedances. therefore necessary external components tune impedance same antenna structure used these products. antenna presented Application Note used with CC2400, CC2420 CC243x inductor sitting between pins tuned accordingly. addition tuning inductor recommended inductor series with TXRX switch pin. This inductor works choke GHz.
Figure CC24xx Folded Dipole
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Antenna Reference Designs
7.2.1 Reference Designs 868/915/955 Antennas 868/915 operation, offers four reference designs that used with products capable operating these frequencies. Three designs pure antennas other chip antenna conjunction with special trace. designs matched ohm. Thus balun needed products with differential output. first antenna consists bent monopole medium-size, low-cost solution. Figure shows bent monopole antenna board 868/915/955 MHz. More information about this design found Design Note CC1100EM Antenna Reference Design [23].
Figure Bent Monopole 868/915/955
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second antenna consists inverted antenna medium-size, low-cost solution. Figure shows inverted antenna board 868/915/955 MHz. More information about this design found Design Note [25] 868/915/955 Inverted Antenna Reference Design [23].
Figure Inverted Antenna board 868/915/955
third antenna consists meandering monopole antenna medium-size, low-cost solution. Figure shows meandering monopole board 868/915/955 MHz. More information about this design found Design Note [26] 868/915/955 Meandering Monopole Antenna Reference Design [27]
Figure Meandering Monopole Antenna board 868/915/955
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smallest antenna solution provided 868/915/955 shown Figure consists chip antenna from Johanson Technology [12] conjunction with special trace. Design recommendations measurement results presented Design Note [8].
Figure Chip Antenna from Johanson Technology 868/915/955
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Additional Antenna Resources
There exists literature discussing antenna types antenna theory. Several companies offer simulation tools applicable antenna simulation. There also many companies that manufacture antennas also companies offering consultant services custom antenna design. This section lists different antenna resources. Antenna Literature
There exist large number publications covering antennas. Table lists some relevant literature dealing with this topic. Title Antenna Theory Design Antenna Handbook Microwave Design Wireless Systems Author Warren Stutzman Garry Thiele David Pozar
Table Antenna Literature Simulation Tools
Table lists simulation tools that used antenna simulations. list given reference only evaluated these programs. Tool IE3D Momentum HFSS Company Zeland [13] Agilent [14] Ansoft [15]
Table Simulation Tools Antenna Suppliers Consultants
difficult design small effective antennas even chip antenna chosen often necessary perform impedance matching obtain optimum performance. Therefore could wise contact consultant special antenna solution required. Below list companies that sell different antenna solutions offer consultant services. Company Fractus Johanson Technologies Pulse RainSun Vishay Yaego Antenova Badland Linx Technologies Antennasys Research Pinyon page http://www.fractus.com/ http://www.lkproducts.com/ http://www.rainsun.com/ http://www.vishay.com/ http://www.yageo.com/ http://www.antenova.com/ http://www.badland.co.uk/ http://www.antennasys.com http://www.lsr.com/ http://www.pinyontech.com/ Expertise Chip antennas Compact antennas Chip antennas Chip antennas Chip antennas Chip antennas Chip antennas Chip antennas Whip antennas Whip antennas Whip antennas Antenna consultant Antenna consultant Directional antennas
Table Antenna Suppliers Consultants
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Summary
This application note gives overview antenna theory, different types antennas available, parameters consider when implementing antenna, antenna measurement methods. Also, presented different antenna reference designs available www.ti.com/lpw also list additional antenna resources. Table lists antenna reference designs available www.ti.com/lpw. This table lists which products different antennas used with, required size implement antenna main properties. does also lists where find more information different designs. Reference design CC2511 Dongle CC2430DB CC2420DB CC2400DB CC2500 Folded Dipole CC2400 Folded Dipole chip antenna Pinyon Quarter Wave Antenna Pinyon Half Wave Antenna CC1111 Dongle CC1100EM antenna 868/915/955 Inverted Antenna 868/915/955 Meandering Monopole antenna Products products products CC2500 CC2550 CC2510 CC2511 CC2400 CC2420 CC2430 CC2431 products products products 868/915/955 products 868/915/955 products 868/915/955 products 868/915/955 products Size 15.2 25.7 Properties Meander Antenna Small size easy tune Antenna Small size easy tune Omnidirectional Folded Dipole Antenna Large size hard tune High gain Folded Dipole Antenna Large size hard tune High gain Chip Antenna Small size easy tune Medium performance Slot Antenna Large size hard tune High gain cost Slot Antenna Very large size hard tune High gain cost Chip Antenna Small size easy tune Bent Monopole Antenna Medium size easy tune Inverted Antenna Medium size easy tune Meandering Monopole Antenna Medium size easy tune Doc. AN043 DN007
46.0
DN004
48.2
AN040
AN048
DN026 DN028 DN027 DN029 DN016 DN008 DN023 DN024
39.0 37.0 43.0 20.0 38.0 24.0
Table Reference designs available www.ti.com/lpw.
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There also general antenna documentation available www.ti.com/lpw AN058 Antenna Selection Guide AN003 Antennas Application Report ISM-Band Antennas (SWRA161) (SWRA088) (SWRA046A)
ambition provide excellent design application notes design-in process will easier quicker. With designs, antenna design critical stage able achieve best possible link budget specific application. antenna application notes updated regularly updated with designs. antenna designs that released free charge used directly final application design. antenna basic form, IFA, patch, spiral generally free from patent infringement because these well known designs that have been around many years. When antenna adapted from "standard format"; then antennas more than likely protected through patents. important keep this mind when developing antenna. Many antenna patents collide with each other which company original valid long discussion. advisable keep standard text book antenna designs when developing antenna avoid legal discussions. This document covers large amount various antenna design antenna concepts. ambition provide wide spectrum antenna designs that final application choose optimum solution their needs. There general recommendations particular antenna supplier antenna type.
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References
AN001 Regulations License Free Transceiver Operation (swra090.pdf) AN032 Regulations (swra060.pdf) AN043 Small Size antenna (swra117.pdf) DN007 Inverted Antenna (swru120.pdf) DN004 Folded Dipole Antenna CC25xx (swra118.pdf) AN040 Folded dipole antenna CC2400, CC2420 CC2430/31 (swra093.pdf) AN048 2.4GHz Chip Antenna (swra092.pdf) DN016 Compact 868/915 Antenna Design (swra160.pdf) DN008 antenna (swru121.pdf) [10] DN001 Antenna Measurement with Network Analyzer (swra096.pdf) [11] Fractus: http://www.fractus.com [12] Johanson Technology: [13] Zeland: http://www.zeland.com/ [14] Agilent: [15] Ansoft: [16] CC2511 USB-Dongle Reference Design (swrc062.zip) [17] CC2430DB Reference Design (swrr034.zip) [18] CC2420DB Reference Design (swrr019.zip) [19] CC2400DB Reference Design (swrr020.zip) [20] CC25xxEM Folded Dipole Reference Design (swrc065.zip) [21] CC2400EM Folded Dipole Reference Design (swra093a.zip) [22] CC1111 Dongle Reference Design (swrr049.zip) [23] CC1100EM Antenna Reference Design (swru122.zip) [24] CC1110EM IIFA Reference Design (swrr058.zip) [25] DN023 868/915 Inverted Antenna Design (swra228a.pdf) [26] DN024 868/915 Meandering Monopole Antenna (swra227a.pdf)
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[27] CC1110EM Meander Antenna Reference Design (swra059.zip) [28] DN026 CC2430 with wave Pinyon Antenna Design Note (swra251.pdf) [29] DN027 CC2430 with half wave Pinyon Antenna Ref. Design Note (swra252.pdf) [30] DN028 CC2510 with wave Pinyon Antenna Ref. Design Note (swra253.pdf) [31] DN029 CC2510 with half wave Pinyon Antenna Ref. Design Note (swra254.pdf) [32] CC2430 with wave Pinyon Antenna Ref. Design (swrc114.zip) [33] CC2430 with half wave Pinyon Antenna Ref. Design (swrc113.zip) [34] CC2510 with wave Pinyon Antenna Ref. Design (swrc116.zip) [35] CC2510 with half wave Pinyon Antenna Ref. Design (swrc115.zip) [36] DN018 Range Measurements Open Field Enviroment (swra169.pdf)
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Appendices
11.1.1 500MHz Chip Antenna YAGEO
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11.1.2 916MHz Chip Antennas Rainsun
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General Information
12.1 Document History
Revision SWRA161 SWRA161A Date 2007-11-26 2009-06-01 Description/Changes Initial release. Updated
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IMPORTANT NOTICE
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