CDMA EV-DO vs HSPA Network Technology
CDMA EV-DO thiab HSPA yog 3G network thev naus laus zis. CDMA EV-DO yog ib kauj ruam mus rau lub xov tooj ntawm tes broadband technology muaj peev xwm xa cov ntaub ntawv tus nqi siab tshaj 2Mbps nyob rau hauv ib puag ncig mobile. Nws yog ib qho tseem ceeb uas EVDO thev naus laus zis siv ntau yam txuj ci uas siv los ntawm HSPA thaum ua tiav cov txiaj ntsig zoo suav nrog turbo coding, hloov kho cov tswv yim thiab lwm yam. ntawm qhov siab tshaj plaws.
CDMA EV-DO (CDMA Evolution Data Optimised)
CDMA EV-DO muaj peb qhov kev tshaj tawm loj raws li tau teev tseg los ntawm 3GPP2 raws li ib feem ntawm CDMA 2000 tus qauv uas yog
o CDMA2000 1xEV-DO Release 0 (Rel 0)
o CDMA2000 1xEV-DO Revision A (Rev A)
o CDMA2000 1xEV-DO Revision B (Rev B)
Nws yog qhov tseem ceeb uas tam sim no xa tawm cov tes hauj lwm siv Tso Tawm 0 thiab Kho A nrog 2.4 Mbps thiab 3.1 Mbps downlinks nrog uplinks 153kbps thiab 1.8 Mbps feem. Qhov bandwidth ntawm cov xov tooj cua siv ntawm no yog 1.25MHz uas ua rau cov ntaub ntawv qis dua piv rau UMTS. Qhov tseem ceeb ntawm cov hom kev tes hauj lwm no yog tias lawv cov backend yog tag nrho cov pob ntawv raws li lub network. Kev Kho Kho A tes hauj lwm muaj peev xwm xa cov VoIP zoo vim tias qhov uplink muaj cov ntaub ntawv zoo ib yam li HSUPA. Nws yog ib qho tseem ceeb uas Kev Kho B hom tes hauj lwm tseem tsis tau raug coj mus muag.
HSPA (High Speed Packet Access)
HSPA yog cov lus siv los hais txog HSDPA (3GPP Tso Tawm 5) thiab HSUPA (3GPP Tso Tawm 6), uas yog pob ntawv raws li thev naus laus zis Evolved muaj cov ntaub ntawv ntau dua piv rau 3G thiab GPRS. HSPA + lossis HSPA (Tshaj 7 thiab tshaj tawm) kuj tseem nyob hauv tsev neeg HSPA thiab nws yuav ua raws li 3GPP LTE cov qauv. Feem ntau nws yog hu ua thev naus laus zis rau 3.5G tes hauj lwm. Txoj kev xav HSPA cov ntaub ntawv tuaj yeem mus txog 14.4 Mbps downlink thiab 5.8 Mbps uplink ntawm qhov siab tshaj plaws uas yog 3-4 npaug ntawm 3G downlink speeds uas twb muaj lawm thiab 15 npaug siab dua GPRS. Tab sis cov tes hauj lwm tam sim no muaj peev xwm muab 3.6Mbps downlink thiab 500 kbps rau 2Mbps uplink feem ntau ntawm cov xov tooj cua channel bandwidth ntawm 5MHz. Thaum txhim kho cov tes hauj lwm rau HSPA los ntawm 3G (WCDMA) nws yuav tsum tau hloov cov downlink uas twb muaj lawm rau HSDPA (High Speed Downlink Packet Access) thev naus laus zis thiab uplink rau HSUPA (High Speed Uplink Packet Access) thev naus laus zis. Nws yog qhov tseem ceeb tias cov kev hloov kho tshiab no feem ntau yog hloov kho software ntau dua li kho vajtse hloov kho rau feem ntau ntawm WCDMA tes hauj lwm. Cov ntaub ntawv siab dua tuaj yeem ua tau vim qhov kev txiav txim siab dua cov qauv kev hloov pauv xws li 16QAM txog 64 QAM (Quadrature Amplitude Modulation) nrog MIMO (Ntau Cov Khoom Siv Tawm Ntau Qhov Tawm) thev naus laus zis.
Qhov txawv ntawm CDMA EV-DO thiab HSPA
1. CDMA EV-DO xov tooj cua interface bandwidth yog 1.25MHz thiab HSPA siv 5MHz bandwidth.
2. Hnub tim tus nqi rau CDMA EV-DO yog nyob ib ncig ntawm 2Mbps hauv downlink thiab HSPA muaj peev xwm muab cov nqi siab tshaj txog 14.4 Mbps hauv downlink (HSDPA).
3. Cov ntaub ntawv tus nqi rau CDMA EV-DO uplink yog 153kbps pib los ntawm Kev Tshaj Tawm 0 nyob rau hauv ib tus neeg nqa khoom thiab HSPA muaj peev xwm muab kev ceev uplink mus txog 5.8 Mbps siv HSUPA.
4. CDMA EV-DO tus qauv yog tsim rau 3G tes hauj lwm feem ntau thiab HSPA raug suav tias yog 3.5 G network technology.
