Umgama wonxibelelwano onokufikelelwa yinkqubo yonxibelelwano engenazingcingo umiselwa zizinto ezahlukeneyo ezifana nezixhobo ezahlukeneyo ezenza inkqubo kunye nemeko-bume yonxibelelwano. Ubudlelwane phakathi kwazo bungabonakaliswa ngolu hlobo lulandelayo lomgama wonxibelelwano.
Ukuba amandla okudlulisa esixhobo sokudlulisa senkqubo yonxibelelwano yi-PT, inzuzo ye-antenna yokudlulisa yi-GT, kwaye ubude bomda osebenzayo yi-λ. Uvakalelo lwesixhobo sokwamkela yi-PR, inzuzo ye-antenna yokwamkela yi-GR, kwaye umgama phakathi kwe-antenna yokwamkela kunye nokudlulisa yi-R, ngaphakathi komgama obonakalayo nakwindalo esingqongileyo ngaphandle kokuphazamiseka kwe-electromagnetic, kukho ubudlelwane obulandelayo:
I-PT(dBm)-PR(dBm)+GT(dBi)+GR(dBi)=20log4pr(m)/l(m)+Lc(dB)+ L0(dB) Kwifomyula, i-Lc kukulahleka kokufakwa kwe-feeder ye-antenna ethumela isikhululo sesiseko; i-L0 kukulahleka kwamaza erediyo ngexesha lokusasazeka.
Xa kuyilwa inkqubo, kufuneka kushiywe umda owaneleyo kwinto yokugqibela, ilahleko yokusasazeka kwamaza erediyo L0.
Ngokubanzi, umda we-10 ukuya kwi-15 dB uyafuneka xa kudlula emahlathini nakwizakhiwo zoluntu; umda we-30 ukuya kwi-35 dB uyafuneka xa kudlula kwizakhiwo zekhonkrithi eziqinisiweyo.
Kwi-800MH, 900ZMHz CDMA kunye neebhendi ze-GSM frequency, kukholelwa ngokubanzi ukuba inqanaba lomlinganiselo wokufumana kwiifowuni eziphathwayo limalunga ne--104dBm, kwaye isignali yokwenyani efunyenweyo kufuneka ibe ngaphezulu kwe-10dB ukuqinisekisa umlinganiselo ofunekayo wesignali-kwingxolo. Enyanisweni, ukuze kugcinwe unxibelelwano oluhle, amandla afunyenweyo adla ngokubalwa njenge--70 dBm. Cinga ukuba isikhululo sesiseko sineeparameter ezilandelayo:
Amandla okudlulisa yi-PT = 20W = 43dBm; amandla okwamkela yi-PR = -70dBm;
Ilahleko ye-feeder yi-2.4dB (malunga ne-60m feeder)
I-antenna efumana ifowuni ephathwayo ifumana inzuzo ye-GR = 1.5dBi;
Ubude bomda obusebenzayo λ = 33.333cm (ilingana ne-frequency f0 = 900MHz);
Le equation yonxibelelwano ingentla iya kuba:
43dBm-(-70dBm)+ GT(dBi)+1.5dBi=32dB+ 20logr(m) dB +2.4dB + ilahleko yokusasazeka L0
114.5dB+ GT(dBi) -34.4dB = 20logr(m)+ ilahleko yokusasazeka L0
80.1dB+ GT(dBi) = 20logr(m)+ ilahleko yokusasazeka L0
Xa ixabiso elikwicala lasekhohlo lefomula engentla likhulu kunexabiso elikwicala lasekunene, oko kukuthi:
I-GT(dBi) > 20logr(m)-80.1dB+ilahleko yokusasazeka L0. Xa ukungalingani kuqhubeka, kunokucingelwa ukuba inkqubo inokugcina unxibelelwano oluhle.
Ukuba isikhululo sesiseko sisebenzisa i-antenna yokudlulisa ejikelezayo ene-GT=11dBi kwaye umgama phakathi kwee-antenna zokudlulisa nezokwamkelayo yi-R=1000m, i-equation yonxibelelwano iba yi-11dB>60-80.1dB+propagation loss L0, oko kukuthi, xa ilahleko yokusasaza i-L0<31.1dB, unxibelelwano oluhle lunokugcinwa kumgama we-1 km.
Phantsi kweemeko ezifanayo zokulahleka kokusasazeka njengoko zikhankanyiweyo ngasentla, ukuba i-antenna ethumelayo ifumana i-GT = 17dBi, oko kukuthi, ukwanda kwe-6dBi, umgama wonxibelelwano ungaphindwa kabini, oko kukuthi, r = 2 km. Ezinye zinokufunyanwa ngendlela efanayo. Nangona kunjalo, kufuneka kuqatshelwe ukuba i-antenna yesikhululo sesiseko ene-GT yokufumana i-17dBi inokuba nophahla olufana nefeni kuphela olunobubanzi be-beam obuyi-30°, 65° okanye 90°, njl.njl., kwaye ayinakugcina uphahla oluhambelanayo.
Ukongeza, ukuba i-antenna ethumelayo ifumana i-GT=11dBi ingatshintshanga kubalo olungentla, kodwa imeko-bume yokusasazeka iyatshintsha, ilahleko yokusasazeka i-L0=31.1dB-20dB=11.1dB, ngoko ilahleko yokusasazeka ye-20dB enciphisiweyo iya kwandisa umgama wonxibelelwano ngokuphindwe kalishumi, oko kukuthi, i-r=10 km. Ixesha lokulahleka kokusasazeka linxulumene nendawo ejikelezileyo ye-electromagnetic. Kwiindawo zasezidolophini, kukho izakhiwo ezininzi eziphakamileyo kwaye ilahleko yokusasazeka inkulu. Kwiindawo zasemaphandleni zasezidolophini, izindlu zasefama ziphantsi kwaye azininzi, kwaye ilahleko yokusasazeka incinci. Ke ngoko, nokuba useto lwenkqubo yonxibelelwano lufana ncamashi, uluhlu olusebenzayo lokugubungela luya kwahluka ngenxa yomahluko kwindawo yokusetyenziswa.
Ngoko ke, xa ukhetha ii-antenna eziya kwicala ngalinye, eziya kwicala elinye kunye neefom ze-antenna eziya kwicala eliphezulu okanye eziya kwicala elinye, kuyimfuneko ukuqwalasela ukusebenzisa ii-antenna zesikhululo sesiseko seentlobo ezahlukeneyo kunye neenkcukacha ngokweemeko ezithile zenethiwekhi yonxibelelwano lweselula kunye nendawo yesicelo.
Ukuze ufunde okungakumbi ngee-antenna, nceda undwendwele:
Ixesha leposi: Julayi-25-2025
