Yintoni umsebenzi we-eriyali kamabonakude?

iindaba 4

Njengenxalenye eyimfuneko yonxibelelwano olungenazingcingo, umsebenzi osisiseko we-eriyali kukukhanya kunye nokufumana amaza erediyo.Umsebenzi kukuguqula i-electromagnetic wave ukusuka kwisikhululo sikamabonwakude ukuya kumbane wesignali ukuya kumaza aphezulu.

Indlela esebenza ngayo i-eriyali ye-TV kukuba xa i-electromagnetic wave isiya phambili, ibetha i-eriyali yesinyithi, inqumle umgca wemagnethi, kwaye yenza amandla ombane, nto leyo engumbane womqondiso.

Njengenxalenye ebalulekileyo yenkqubo yonxibelelwano, ukusebenza kwe-antenna kuchaphazela ngokuthe ngqo isalathisi senkqubo yonxibelelwano.Umsebenzisi kufuneka anikele ingqalelo ekusebenzeni kwayo kuqala xa ekhetha i-eriyali.

Esinye sezibonakaliso eziphambili ze-antenna kukuzuza, okuyimveliso ye-coefficient ye-directional coefficient kunye nokusebenza kakuhle, kunye nokubonakaliswa kobukhulu bemitha ye-antenna okanye amaza afunyenweyo.Ukukhethwa kobukhulu bokuzuza kuxhomekeke kwiimfuno ze uyilo lwesixokelelwano sendawo yokugubungela amaza kanomathotholo.Ngamafutshane, phantsi kweemeko ezifanayo, okukhona inzuzo iphezulu, kokukhona umgama wokusasazwa kwamaza kanomathotholo.Ngokubanzi, i-eriyali yesitishi esisezantsi ithatha i-eriyali yenzuzo ephezulu, kwaye i-eriyali yesitishi esiphathwayo ithatha i-eriyali yenzuzo ephantsi.

I-eriyali efumana i-TV ngokuqhelekileyo yi-eriyali yomgca (i-eriyali efumana isathelayithi yi-eriyali yomphezulu), ngokuhambelana noluhlu lwamafrikhwensi ophawu olufunyenweyo oluphezulu lunokwahlulwa lube yi-eriyali ye-VHF, i-eriyali ye-UHF kunye ne-antenna yonke;Ngokobubanzi bebhendi yobubanzi be-eriyali efumanayo, yahlulwe yaba yi-eriyali yetshaneli enye kunye ne-eriyali ephindaphindiweyo.Ngokwesakhiwo sayo, inokwahlulwa ibe yi-antenna yesikhokelo, i-antenna yeringi, i-antenna ye-fishbone, i-antenna ye-log periodic njalo njalo.

Inkqubo yeTV evulelekileyo efunyenwe yinkqubo kamabonakude wentambo ibandakanya ubukhulu becala amabhendi amabini: ⅵ (itshaneli 1-4) kunye ⅷ (itshaneli 6-12) kwibhendi yeVHF kunye ne-UIV (itshaneli 13-24) kunye ne-UV (itshaneli 25- 48) kwiqela le-UHF.Kwibhendi yefrikhwensi yeVHF, i-eriyali yetshaneli ekhethekileyo efumana isignali yeTV yetshaneli ethile ikhethwa ngokubanzi, kwaye eyona ndawo ilungileyo yokufumana ikhethwa ukufakela, ukuze ibe neenzuzo zenzuzo ephezulu, ukukhetha okulungileyo kunye nolwalathiso olomeleleyo.Nangona kunjalo, i-eriyali eyinxalenye yebhendi esetyenziswa ku-ⅵ kunye no-ⅷ kunye ne-eriyali yetshaneli yonke esetyenziswa kwi-VHF inebhendi ebanzi yamaza kunye nenzuzo ephantsi, efanelekileyo kuphela kwiinkqubo ezincinci.Kwibhendi yefrikhwensi ye-UHF, iperi yee-eriyali zebhendi zinokufumana iinkqubo zikamabonwakude zamajelo amaninzi ahlukaniswe ngokusondeleyo.


Ixesha lokuposa: Aug-25-2022