Video: Qhov txawv ntawm LTE FDD thiab LTE TDD yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
FDD LTE thiab TDD LTE yog ob txawv qauv ntawm LTE 4G technology. LTE yog ib tug high-speed wireless technology los ntawm 3GPP tus qauv. LTEFDD siv ib tug khub spectrum uas los ntawm txoj kev tsiv teb tsaws chaw ntawm 3G network, whereas TDD LTE siv cov spectrum uas tsis sib xws uas hloov zuj zus los ntawm TD-SCDMA.
Sib piv, 4g LTE FDD thiab TDD yog dab tsi?
LTE Nws tuaj yeem siv ob qhov sib faib zaus thiab faib sijhawm, FDD & TDD (TD- LTE ) cov ntaub ntawv duplex kom haum rau uplink thiab downlink. LTEFDD siv cov spectrum ua ke tau suav hais tias yog txoj kev tsiv teb tsaws chaw rau UMTS 3G cov kev pabcuam uas feem ntau siv spectrum.
Tsis tas li ntawd, qhov twg zoo dua TDD lossis FDD? FDD xav tau cov chaw nres tsheb tsawg dua TDD Nyob rau hauv qhov kev pab them nqi-txheej system sib piv siv tib zaus band, lub TDD system xav tau 31% ntau basestations dua FDD thaum siv 1: 1 TDD system thiab 65% ntau lub hauv paus chaw nres tsheb thaum siv 2: 1 TDD qhov system. Higherfrequency bands yuav tsum tau ntau dua basestations.
Ntawm no, LTE TDD yog dab tsi?
LTE yog lub npe raug cai rau 4G, txhais tau tias Long TermEvolution. Tab sis zoo ib yam li Asmeskas qhov sib txawv, tsis sib xws GSM thiab CDMA xov tooj tshuab, muaj ob qho qauv sib txawv rau LTE -- TDD thiab FDD. Ob lub ntsiab lus no sawv cev rau 'time-division duplexing' thiab 'frequency-divisionduplexing'.
Lub ntsiab lus ntawm FDD LTE yog dab tsi?
LTE yog txhais los txhawb ob qho tib si pairedspectrum rau Frequency Division Duplex ( FDD ) thiab unpairedspectrum rau Time Division Duplex (TDD). LTE FDD siv pairedspectrum uas los ntawm txoj kev tsiv teb tsaws chaw ntawm 3G network whereas TDD LTE siv unpaired spectrum uas hloov los ntawm TD-SCDMA.
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