Nzira yekuwana kuenderana kweimpedance kwema waveguides? Kubva padzidziso ye transmission line mu microstrip antenna theory, tinoziva kuti mitsara yakakodzera ye series kana parallel transmission inogona kusarudzwa kuti iwane kuenderana kweimpedance pakati pemitsara ye transmission kana pakati pemitsara ye transmission nemitoro kuti iwane kutumirwa kwesimba rakawanda uye kurasikirwa kushoma kwe reflection. Nheyo imwechete ye impedance matching mu microstrip lines inoshanda kune kuenderana kweimpedance mu waveguides. Reflections mu waveguide systems inogona kutungamira kune impedance mismatches. Kana impedance ikaora, mhinduro yacho yakafanana neye transmission lines, ndiko kuti, kuchinja kukosha kunodiwa. Lumped impedance inoiswa panzvimbo dzakatarwa kare mu waveguide kuti ikunde kusawirirana, nokudaro ichibvisa mhedzisiro ye reflections. Nepo transmission lines ichishandisa lumped impedances kana stubs, waveguides inoshandisa simbi blocks dzemhando dzakasiyana.
mufananidzo 1: Ma "waveguide irises" uye circuit yakaenzana, (a) Capacitive; (b) inductive; (c) resonant.
Mufananidzo 1 unoratidza mhando dzakasiyana dzekubatanidza impedance, zvichitora chero mafomu anoratidzwa uye zvinogona kuva capacitive, inductive kana resonant. Kuongorora kwemasvomhu kwakaoma, asi tsananguro yepanyama haisiyo. Tichifunga nezve capacitive metal strip yekutanga mumufananidzo, zvinogona kuonekwa kuti mukana waivapo pakati pemadziro epamusoro nepasi e waveguide (mu dominant mode) ikozvino uripo pakati penzvimbo mbiri dzesimbi dziri pedyo, saka capacitance ndiyo The point inowedzera. Kusiyana neizvi, metal block muMufananidzo 1b inobvumira current kuti iyerere kwaisina kuyerera kare. Pachava nekuyerera kwe current mu electric field plane yakasimbiswa kare nekuda kwekuwedzera kwe metal block. Naizvozvo, kuchengetwa kwesimba kunoitika mumunda wemagineti uye inductance panzvimbo iyoyo ye waveguide inowedzera. Pamusoro pezvo, kana chimiro nenzvimbo yesimbi ring muMufananidzo c zvakagadzirwa zvine musoro, inductive reactance uye capacitive reactance inounzwa ichave yakaenzana, uye aperture ichave parallel resonance. Izvi zvinoreva kuti kuenderana kweimpedance uye kugadzirisa main mode kwakanaka kwazvo, uye shunting effect yeiyi mode ichave shoma. Zvisinei, mamwe mamodhi kana mafrequency achaderedzwa, saka resonant metal ring inoshanda se bandpass filter uye semode filter.
mufananidzo 2:(a) mapositi ekutungamira mafungu;(b) muchina wekubatanidza screw mbiri
Imwe nzira yekuchinjisa inoratidzwa pamusoro apa, apo pombi yesimbi ine cylindrical inotambanuka kubva kune rimwe divi rakafara ichipinda muwaveguide, iine simba rakafanana nesimbi strip maererano nekupa bumped reactance panzvimbo iyoyo. Pombi yesimbi inogona kuva capacitive kana inductive, zvichienderana nekuti inosvika kure sei muwaveguide. Chaizvoizvo, nzira iyi yekufananidza ndeyekuti kana pillar yesimbi yakadaro ichipinda zvishoma muwaveguide, inopa capacitive susceptance panzvimbo iyoyo, uye capacitive susceptance inowedzera kusvika kupinda kwacho kwava chikamu chimwe muzvina chewavelength. Panguva ino, series resonance inoitika. Kupinda kwakawedzerwa kwepombi yesimbi kunoguma ne inductive susceptance inopihwa iyo inoderera sezvo insertion ichiwedzera kukwana. Kusimba kwe resonance pakuiswa kwepakati kwakaenzana nedhayamita yekoramu uye kunogona kushandiswa sefirita, zvisinei, mune iyi kesi inoshandiswa se band stop filter kutumira modes dzemhando yepamusoro. Kana tichienzanisa nekuwedzera impedance yesimbi strips, mukana mukuru wekushandisa simbi poles ndewekuti dziri nyore kugadzirisa. Semuenzaniso, screw mbiri dzinogona kushandiswa sezvishandiso zvekugadzirisa kuti pave nekuenderana kwakanaka kwewaveguide.
Mitoro inodzivisa uye zvinoderedza simba:
Kufanana nedzimwe nzira dzekutumira mafungu, dzimwe nguva mawaveguides anoda kuenderana kwakakwana kweimpedance uye kugadziridzwa kwemitoro kuti anyatso tora mafungu anouya pasina kuratidzwa uye kuti asanyanya kunzwa mafrequency. Chimwe chezvishandiso zvematerminals akadaro ndechekuita zviyero zvakasiyana zvesimba pane system pasina kuburitsa simba.
mufananidzo 3 waveguide resistance load(a)single taper(b)double taper
Kugumira kunonyanya kusimba kwesimba chikamu che dielectric inorasikirwa chakaiswa pamagumo e waveguide uye chakatetepa (nemuromo wakatarisa kune wave iri kuuya) kuitira kuti isakonzere kupenya. Iyi nzira inorasikirwa inogona kutora upamhi hwese hwe waveguide, kana kuti inogona kutora pakati pemugumo we waveguide chete, sezvakaratidzwa muMufananidzo 3. Taper inogona kuva imwe chete kana kaviri uye inowanzova nehurefu hwe λp/2, nehurefu hwese hwema wavelengths maviri. Kazhinji inogadzirwa nemaplates e dielectric akadai segirazi, akafukidzwa ne carbon film kana girazi remvura kunze. Kune mashandisirwo ane simba guru, ma terminals akadaro anogona kuwedzerwa ma heat sinks kunze kwe waveguide, uye simba rinounzwa ku terminal rinogona kupararira kuburikidza ne heat sink kana kuburikidza nekumanikidzwa kwemhepo inotonhorera.
mufananidzo 4 Chinotamisa vane chinofambiswa
Zvidziviriro zveDielectric zvinogona kubviswa sezvakaratidzwa paMufananidzo 4. Kana zvaiswa pakati peguide, zvinogona kutamiswa kubva pakati peguide, uko zvichapa kudzikiswa kukuru, kusvika kumucheto, uko kudzikiswa kunoderedzwa zvakanyanya sezvo simba remagetsi remuchina wedominant mode rakaderera zvikuru.
Kudzikira kwesimba mu waveguide:
Kuderedzwa kwesimba rema waveguides kunonyanya kusanganisira zvinhu zvinotevera:
1. Kufungisisa kubva pakusagadzikana kwemugwara remafungu kana zvikamu zvegwara remafungu zvisina kumira zvakanaka
2. Kurasikirwa kunokonzerwa nekufamba kwemvura mumadziro ewaveguide
3. Kurasikirwa kweDielectric mumafungu akazara
Zviviri zvekupedzisira zvakafanana nekurasikirwa kunoenderana mumitsara ye coaxial uye zvese zviri zvidiki. Kurasikirwa uku kunoenderana nezvinhu zvemadziro uye kuomarara kwazvo, dielectric inoshandiswa uye frequency (nekuda kwemhedzisiro yeganda). Kune brass conduit, huwandu hwacho hunobva pa4 dB/100m pa5 GHz kusvika 12 dB/100m pa10 GHz, asi kune aluminium conduit, huwandu hwacho hwakaderera. Kune sirivha-coated waveguides, kurasikirwa kunowanzova 8dB/100m pa35 GHz, 30dB/100m pa70 GHz, uye pedyo ne500 dB/100m pa200 GHz. Kuderedza kurasikirwa, kunyanya pama frequency akakwira, waveguides dzimwe nguva dzinoputirwa (mukati) negoridhe kana platinum.
Sezvambotaurwa, waveguide inoshanda sefirita inopinza mafungu akawanda. Kunyangwe waveguide pachayo isingarasikirwe, mafrequency ari pasi pe cutoff frequency anodzikira zvakanyanya. Kudzikira uku kunokonzerwa nekuratidzwa kwechiedza pamuromo wewaveguide kwete kupararira.
Kubatanidza mafungu ekufambisa:
Kubatana kwewaveguide kunowanzo itika kuburikidza nemaflanges kana zvidimbu zvewaveguide zvakabatana. Basa reflange iyi nderekuona kubatana kwakanaka kwemuchina uye hunhu hwemagetsi hwakakodzera, kunyanya mwaranzi yekunze yakaderera uye kuratidzira kwemukati kwakaderera.
Flange:
Maflange eWaveguide anoshandiswa zvakanyanya mukutaurirana kwema microwave, radar systems, satellite communications, antenna systems, uye laboratory tools mukutsvaga kwesainzi. Anoshandiswa kubatanidza zvikamu zvakasiyana zvewaveguide, kuona kuti kubuda kwemvura nekukanganiswa zvinodzivirirwa, uye kuchengetedza kurongeka kwakarurama kwewaveguide kuti ive nechokwadi chekuti kutumirwa kwakasimba uye nzvimbo chaiyo yema frequency electromagnetic waves. Waveguide yakajairika ine flange kumagumo ese, sezvakaratidzwa muMufananidzo 5.
mufananidzo 5 (a)flange isina chinhu;(b) flange coupling.
Pama frequency akaderera, flange inosungirirwa kana kusungirirwa ku waveguide, nepo pama frequency akakwira, flat butt flat flange inoshandiswa. Kana zvikamu zviviri zvabatanidzwa, ma flange anosungirirwa pamwe chete, asi magumo anofanirwa kupedzwa zvakanaka kudzivirira kusagadzikana mukubatana. Zviri pachena kuti zviri nyore kurongedza zvikamu nemazvo nekumwe kugadzirisa, saka ma waveguides madiki dzimwe nguva ane threaded flanges anogona kusungirirwa pamwe chete ne ring nut. Sezvo frequency ichiwedzera, saizi ye waveguided coupling inoderera, uye coupling discontinuity inokura zvichienderana ne signal wavelength ne waveguide size. Nokudaro, discontinuities pa higher frequency inova yakaoma zvikuru.
mufananidzo 6 (a) Chikamu chakachinjika chekubatanidza choke; (b) maonero ekupedzisira eflange yekuchoke
Kugadzirisa dambudziko iri, pane mukana mudiki unogona kusara pakati pema waveguides, sezvakaratidzwa muMufananidzo 6. Kubatanidza kwechoke kunosanganisira flange yakajairika nechoke flange zvakabatana pamwe chete. Kutsiva miganho inogona kuitika, rin'i yechoke yakatenderera ine chikamu cheL-shaped inoshandiswa muchoke flange kuti iwane kubatana kwakasimba. Kusiyana nema flange akajairwa, choke flanges anonzwa frequency, asi dhizaini yakagadziriswa inogona kuve nechokwadi chekuti bandwidth inonzwisisika (zvichida 10% ye central frequency) iyo SWR isingapfuure 1.05.
Nguva yekutumira: Ndira-15-2024
