eM ow fong-wire antennas Resonant Non-Resonant SL “ wile antenna whose length io muliples a 4), te 2 there nis integer >3 “these are also called Ss 3 hainori + Rewrant antenna ic antenna. teonant antenno is a long cre cotenna. in vineh 4 Ip (07 lod end 15 open urcuit Cor) hot termirated with any toad 4p resonant antennas ane enc is cnnecteol ~ si ancl other enc iS not connected! to any 1a0d | o due to ipeclence mismatch between souice and lead, reflections takes place -hom load enc n Due to existence of incident and rellected way ina slagle antenna , Stancling ways are formed along the lengih of antenna yherefore the vesonant antenna is also called as Standing wave antenna | periodic antenna characteristics of resonant frequency antenna (Radiation pallern: the radiation pattern of resonant antenna \3 bidirectional. due to forward 2 backuod waves (0 Electric het 2): if nz0cld —> ih meven n of 01) Which < enpedernet re) the dp trd is tamicated matching tysween the pauxce Hletions doespot tates places rom lead end to source ord fue 4o the non-existence of reflec waves in o eiegle antenna. 2 travelling waves ore ome along dhe length of tne antenna. therefore non-resonant obtenaas are also conte! 08 bovellingantenna/ Apevicdic ontenna. Ctasacten ‘ Ractolion pattern: tbe roctiation pattern of 119- Fescnunt antenna \s unidirecttengy ise =t0 “the txistonce of travelling (meg, a of moyienum @adia’ Osi tiounidirectional lide Rane] Artenno. No veflection termincitedt With Zo Biclivectional open circuit Resonant Antenna. Nonow Band Arlenna Reflection takes place 3) Frequency Band Reflection act Povaneter Rand of Operation 5. Radligtion pattern 4 Structure No . 2 3 5 = aa 5 eg a8 3 17 1 sg a © aie 3 S|, 2le eg Sa ae agl bh gta ou iam s : = & Brood. band antenna Breadband Antenno. He nee Broodeond antenna 1s a antenna which is eperating ata wide vange Arequenaes cmultiple trequencies band Bead on band antenras having highly directional choroeteristice with loge bandwith these are useful for long distance tommunication is at wide band range like satellite communication T breed casting ,navigation and endAR applications Radio detection ond ranging) Examples of breadband antenna: + Helical antennce 8. Bi- conical antenna. 3 Micoship antenna. 4. How antenna. & [ens antenna. Helical antenna: Hetical antenna. is in the form of helix pitch anal (a): ipa yen tana = ee Har (Yo) = tan! (St) MKsac A concnting we is wnding 7 & bac ees surface with constant spacing behoeen the twins iS form 05 an helix. An helix 15, excited with proper. put then it is considered os helical antenna: fe helical antenna is dotained 4om the onductor vith picper input curent 4k is & braadbandl antenna. which 15. operatecl at Vite and UNE band (30M~ 3006): J provides cireulor polasisotion of ractiation which is useful io satellite communication consttuction details geomettcal parameters) N=00-0f tins Le Length of each tun 5+ spacing behween the 2 tums = Diameter of helix czarcumforence of each turn (helix) d= tadius of aoss section A= Arial tength ot (distance from Battiog poiot 10 ending pol of hetix in aval direchon) NS = pitch ongle pitch angle tt is defined as angle of wiedling in helix which tb the angle between ciumlerence of helix to the Une tangent of hells: Sa eee4 opeation: — DAomal mode of operation (Breaclsicle mode) 4) fiat mode cf operation Cena ire mode) T) Nomal mode of operation: 40 this macle of operation the betiical antenna. Powdles max radiation in the divection of perpencticrubon OS Bicadside made of operation ope fle the yoy axial vatio “br the gven antenney value of 'd componente? ARS Bl fee Wena oho (5 Ae = PR = ash. asr Types of polavisakion: ' Horizontal polarisation —> Ar- «o ie Evol &-0 2 Vertical polavisation > Aro fe FeO hee-0 3 Creulor polarisation > AR=1 fe (Eo! -1Ep! w tlonzontal ellipal polartation —> ditions for draular polarisaHon inkerms of physical parameters For cireautar polarisation Aad ane fo] = asa Ep ip 1 asa 2 Ce asn c+ Vasn ciecuumference =fB1 is the condition for dreulaxx micrasteip Antenna -rmaostrp antenna. is a broadbrcl antenna. which 1s qperating 19 multiple Trequency bands [7 E18 4 low profile antenna. uhich is integrated with other oven: also. i) Radiation conduct ts of radiating pater Ceoraueting plane)ion one-side oF dielecttic substtate (insulator cor) non cenctucting material. which is having grunc! plane (conducting plane) on another side pilerent types of rackating patches: i> a te+, pesign parameters of merostrip > = Length oF radiating patch ) we Ulidth of radiation patch “| H1= thickness OF the dielectric substvate » §= Thickness of radiating patch » er Dielectric constant | nasignrations of rectangulr mitrostrp antenca de 70 design micosbip antenna. there are 2 ways )) Transenissioo Line medet: 70 get the decign etation ot enicrostrip antenna we have 40 use TyJine model theoryjhe design relations are exaluatted based! on Je . epeating frequency Co» pesinant heaurency (on cut-of int width of the patch (to) wisi Ve a (el EHective tength 4b is the length of patch antenna indudin finging fields expansion. 7 les» L+ 20 toe a nt inuemertal tength ot fringing fielo “4 rie Ae SH Gerd nab} 3 Gert = ee ae choracteristics ; a) Radiation patern . Two radiation potters in w= and w-av' planes as Shown to ‘fig ia and tb) Be a sao Pig @) and (6) Nowncilised Radiation pattern fringing field Is responsible -for he vodiation \ythe stratter the & move will be the radiation 6») Bamusidth From he radiation pattern figure it can be noted that MsA’s generally have a very wide beano width, oth lo azimuth ond elevation planes 5 Directivity The directivity of migostyip patch antenna ts given by 2 4)60i0 Gain of 0 yectanguldr rivostrip patch antenna with ain dielecttic © voug! He estimated! between 7-148 ©) Baindwelth “ibe bandwidth decreases with the i voughly as se of 9 Bandwidth= 3-1 SNS ~> As sCvewn increases , the impedence hardwidth lncreouesRetum Loss : > the retum 1085 is defined us the fourier tansfotms of the incident vellected signal 7 be bandividth of 0 patch antenna is shongly py the spacing between the pakb and tor ‘g' represents the losses associated 2 the bandwidth and the Frequency of the patch > filaige @ leads to narra bandwidth and alow efficiency ~7 6 can be reduced: by indeasing the thickness OF the dielechic subshate >> But as the thickness inwenses 50 large faction of the totes! power delivered by the source Hansfowms into a surface waves the surface waves can be minimized oy using E84 stuuctures ie gadar crass -sectign: — *eaeen’ “rhe Ges guidance systems require lou radar cro platforms the RES of a Conventional patch antenna, is high Phe patch is covered with 0 magnetic material to reduce the Res of a convention ~O 4) eficercy ~eThe eHigency of a micosbip antenna is 7k R+Pat he patch antenna Ls Tmpact of alHerent parameters an chavactenistics wuhere By is the radiation power Re is the power dissipated due to conductor lox Pa is the power dissipated due to dielectric ») pdanization potch antennas can be designed to hoe verlical, hovizontal , right band dicular (RHO) OH TELE hand Graular (LHC) polarnations . patch antennas cont he length L and the resonant rec lth WI conttols the input impedance todiation patternpomitiity & of the cubstate conttols be Pegi Held. tower the Er wider will be the shingiog and better will be the radiation Le VrteV iby 1p ‘ebrinking’ qe | Higher values of pamitivily pate arkenna Yhe dleperdience of bandwith on various parameters is g 2 ee ea) Wb oA dectense in & also increases the antenna. banduilth srthe efficiency of the antenna also increases with the lower value of & he Impedance of the antenna increases with ‘he €,