Mtunda wolumikizirana womwe makina olumikizirana opanda zingwe angapeze umatsimikiziridwa ndi zinthu zosiyanasiyana monga zida zosiyanasiyana zomwe zimapanga makinawo ndi malo olumikizirana. Ubale pakati pawo ukhoza kufotokozedwa ndi equation yotsatirayi ya mtunda wolumikizirana.
Ngati mphamvu yotumizira ya chipangizo chotumizira cha makina olumikizirana ndi PT, phindu la antenna yotumizira ndi GT, ndipo kutalika kwa nthawi yogwirira ntchito ndi λ. Kuzindikira kwa cholandirira chipangizo cholandirira ndi PR, phindu la antenna yolandirira ndi GR, ndipo mtunda pakati pa antenna yolandirira ndi yotumizira ndi R, mkati mwa mtunda wowoneka bwino komanso m'malo ozungulira popanda kusokoneza kwa maginito, pali ubale wotsatirawu:
PT(dBm)-PR(dBm)+GT(dBi)+GR(dBi)=20log4pr(m)/l(m)+Lc(dB)+ L0(dB) Mu fomula iyi, Lc ndiye kutayika kwa feeder insertion ya antenna yotumizira siteshoni ya base; L0 ndiye kutayika kwa mafunde a wailesi panthawi yofalitsa.
Popanga dongosololi, malire okwanira ayenera kutsala pa chinthu chomaliza, kutayika kwa kufalikira kwa mafunde a wailesi L0.
Kawirikawiri, malire a 10 mpaka 15 dB amafunika podutsa m'nkhalango ndi nyumba za anthu wamba; malire a 30 mpaka 35 dB amafunika podutsa m'nyumba za konkire zolimbikitsidwa.
Pa ma band a 800MH, 900ZMHz CDMA ndi GSM frequency, anthu ambiri amakhulupirira kuti mulingo wolandirira mafoni ndi pafupifupi -104dBm, ndipo chizindikiro chenicheni cholandirira chiyenera kukhala chokwera ndi 10dB kuti zitsimikizire kuti pali chiŵerengero chofunikira cha chizindikiro-ku-phokoso. Ndipotu, kuti kulumikizana kukhale bwino, mphamvu yolandirira nthawi zambiri imawerengedwa ngati -70 dBm. Tangoganizani kuti siteshoni yoyambira ili ndi magawo otsatirawa:
Mphamvu yotumizira ndi PT = 20W = 43dBm; mphamvu yolandira ndi PR = -70dBm;
Kutayika kwa feeder ndi 2.4dB (pafupifupi 60m feeder)
Kupeza kwa antenna pafoni yam'manja GR = 1.5dBi;
Kutalika kwa nthawi yogwira ntchito λ = 33.333cm (kofanana ndi pafupipafupi f0 = 900MHz);
Chiyanjano cholankhulirana chomwe chili pamwambapa chidzakhala:
43dBm-(-70dBm)+ GT(dBi)+1.5dBi=32dB+ 20logr(m) dB +2.4dB + kutayika kwa kufalikira L0
114.5dB+ GT(dBi) -34.4dB = 20logr(m)+ kutayika kwa kufalikira L0
80.1dB+ GT(dBi) = 20logr(m)+ kutayika kwa kufalikira L0
Ngati mtengo womwe uli kumanzere kwa fomula yomwe ili pamwambapa ndi waukulu kuposa mtengo womwe uli kumanja, ndiye kuti:
GT(dBi) > 20logr(m)-80.1dB+kutayika kwa kufalikira L0. Ngati kusalingana kulipo, zitha kuganiziridwa kuti dongosololi likhoza kusunga kulumikizana kwabwino.
Ngati siteshoni yoyambira ikugwiritsa ntchito antenna yotumizira yolunjika mbali zonse yokhala ndi phindu la GT=11dBi ndipo mtunda pakati pa antenna yotumizira ndi yolandira ndi R=1000m, equation yolumikizirana imakhala 11dB>60-80.1dB+kutayika kwa kufalikira L0, ndiko kuti, pamene kutayika kwa kufalikira L0<31.1dB, kulumikizana kwabwino kumatha kusungidwa mkati mwa mtunda wa 1 km.
Pansi pa mikhalidwe yofanana yotaya kufalikira monga momwe zilili pamwambapa, ngati antenna yotumizira ikupeza GT = 17dBi, ndiko kuti, kuwonjezeka kwa 6dBi, mtunda wolumikizirana ukhoza kuwirikiza kawiri, ndiko kuti, r = makilomita awiri. Zina zitha kuwerengedwa mwanjira yomweyo. Komabe, ziyenera kudziwika kuti antenna ya siteshoni yoyambira yokhala ndi GT yopeza 17dBi ingakhale ndi chophimba chooneka ngati fan chokhala ndi m'lifupi mwa beam ya 30°, 65° kapena 90°, ndi zina zotero, ndipo sichingathe kusunga chophimba chozungulira chilichonse.
Kuphatikiza apo, ngati kuchuluka kwa antenna yotumizira GT=11dBi sikunasinthe pakuwerengera pamwambapa, koma malo ofalitsa akusintha, kutayika kwa kufalitsa L0=31.1dB-20dB=11.1dB, ndiye kuti kutayika kwa kufalitsa kwa 20dB kochepetsedwa kudzawonjezera mtunda wolumikizirana kakhumi, ndiko kuti, r=10 kilomita. Nthawi yotayika kwa kufalitsa ikugwirizana ndi malo ozungulira amagetsi. M'mizinda, muli nyumba zambiri zazitali ndipo kutayika kwa kufalitsa ndi kwakukulu. M'madera akumidzi akumidzi, nyumba za famu ndizochepa komanso zochepa, ndipo kutayika kwa kufalitsa ndi kochepa. Chifukwa chake, ngakhale makonda a makina olumikizirana ali ofanana, kuchuluka kwa kufalikira kogwira ntchito kudzakhala kosiyana chifukwa cha kusiyana kwa malo ogwiritsira ntchito.
Chifukwa chake, posankha ma antenna olunjika onse, olunjika ndi mitundu ya ma antenna okwera kapena otsika, ndikofunikira kuganizira kugwiritsa ntchito ma antenna a base station amitundu yosiyanasiyana ndi zofunikira malinga ndi momwe zilili ndi netiweki yolumikizirana yam'manja ndi malo ogwiritsira ntchito.
Kuti mudziwe zambiri zokhudza ma antenna, chonde pitani ku:
Nthawi yotumizira: Julayi-25-2025
