GSM vs 3G Network Technology
GSM (Lub Ntiaj Teb Txheej Txheem rau Kev Sib Txuas Lus Sib Txuas Lus) thiab 3G (3rd Generation mobile technology) yog ob qho tib si kev sib txuas lus ntawm tes uas tau hloov zuj zus mus rau lub sijhawm. GSM tau tshaj tawm raws li tus qauv hauv xyoo 1989 thaum 3G tau thov los ntawm 3GPP (3rd Generation Partnership Project) hauv xyoo 2000. GSM thiab 3G siv ntau yam kev siv thev naus laus zis sib txawv rau cov chaw nres tsheb xov tooj ntawm tes kom nkag mus rau hauv lub network, uas kuj qhia txog kev hloov pauv hauv lub network thiab..
GSM
Feem ntau, GSM, suav tias yog (2G) 2nd Generation mobile technology yog raws li cov thev naus laus zis digital. GSM yog qhov nrov tshaj plaws 2G thev naus laus zis thaum piv nrog lwm yam 2G thev naus laus zis tau qhia hauv tib lub xyoo caum, xws li IS-95 hauv North America thiab PDC (Kev Sib Txuas Tus Kheej Digital) hauv Nyij Pooj. Tom qab nrhiav tau ntawm ETSI (European Telecommunication Standard Institute) hauv 1989, GSM tau dhau los ua tus qauv nrov tshaj plaws hauv ntau lub tebchaws. GSM huab cua interface siv cov sijhawm sib cais hauv cov zaus sib cais rau txhua tus neeg siv, yog li ntawd, yuav muaj kev cuam tshuam tsawg dua ntawm ob tus neeg siv sib cais nkag mus rau hauv lub network. GSM rov siv tib lub xov tooj zaus hauv cov hlwb uas tsis yog qhov sib koom ua ke kom cov kev cuam tshuam ntawm tes tau txo qis ntawm cov neeg nyob sib ze. Circuit hloov cov ntaub ntawv tus nqi txhawb hauv GSM yog 14.4 kbps.
3G
3G yog raws li IMT-2000 (International Mobile Telecommunication) specifications luam tawm los ntawm International Telecommunication Union. Txawv 3G technologies hloov zuj zus los ntawm txawv teb chaws thiab European tus qauv hu ua W-CDMA (Wideband - Code Division Multiple Access), North American ib tug hu ua cdma2000 thaum TD-SCDMA (Lub Sijhawm Division - Synchronous CDMA) tus qauv siv los ntawm Tuam Tshoj. Tam sim no, 3GPP tau tshaj tawm cov qauv sib txawv ntawm 3G qauv nrog cov lej tso tawm R99, R4, R5, R6 thiab R7. 3GPP tso tawm 8 thiab 9 yog suav tias yog 4th Generation Technologies uas ua rau LTE (Long Term Evolution). 3G technologies xws li WCDMA thiab cdma2000 siv Frequency Division Duplexing thaum TD-SCDMA siv Time Division Duplexing. Cov kab ke sib txuas lus yuav tsum xa cov ntaub ntawv siab tshaj plaws txog li 200kbps kom ua tau raws li IMT-2000 tus qauv whereas raws li 3GPP R99 tus qauv ncov cov ntaub ntawv tus nqi yuav tsum yog 384kbps.
GSM vs 3G
Thaum muab piv GSM thiab 3G thev naus laus zis, 3G tso cai rau cov ntaub ntawv ntau dua (bandwidth) rau cov neeg siv kawg dua li GSM. Tsis tas li, 3G thev naus laus zis siv pob ntawv hloov tshuab rau cov ntaub ntawv thaum GSM siv cov ntaub ntawv hloov hluav taws xob.
Ntau txoj kev nkag tau siv hauv GSM yog TDMA (Time Division Multiple Access) thiab FDMA (Frequency Division Multiple Access), whereas, hauv 3G nws yog WCDMA. Yog li ntawd nyob rau hauv 3G txhua tus neeg siv kis tau nws cov teeb liab nyob rau hauv tag nrho cov bandwidth, yog li ntawd, lwm tus neeg siv pom nws li pseudo dawb suab nrov (WCDMA) whereas, nyob rau hauv GSM, txhua tus neeg siv xaiv cais zaus channel thiab cais lub sij hawm qhov chaw nyob rau hauv uas channel sib txuas lus. GSM yog suav tias yog 2nd Generation thev naus laus zis thaum 3G yog 3rd Generation cov thev naus laus zis tshiab tshaj plaws los ntawm 3GPP.
Thaum muab piv cov qauv tsim, 3G tau qhia cov npe tshiab hu ua Node-B thiab RNC (Xov tooj cua Network Controller) los hloov cov BTS (Base Transceiver Station) thiab BSC (Base Station Controller) raws li. Cov kev hloov kho vaj tse no yuam kom feem ntau ntawm cov neeg siv xov tooj ntawm tes los nqis peev dua (tsawg dua lub sijhawm los hloov kho) hauv 3G thev naus laus zis nyob rau sab saum toj ntawm GSM network uas twb muaj lawm, vim tias tsis muaj kev sib txuas ntawm cov thev naus laus zis. Tsis tas li ntawd, cov khoom siv txawb tau hloov kho los txhawb ob lub thev naus laus zis tsuas yog vim li cas saum toj no.
Ib lub hom phiaj tseem ceeb tshaj plaws ntawm kev hloov pauv ntawm GSM mus rau 3G, yog qhov muaj zog thiab muaj txiaj ntsig ntawm kev nkag mus rau hauv internet. 3G muab cov ntaub ntawv ntau dua thaum piv nrog GSM los ntawm kev siv tau zoo ntawm cov spectrum uas twb muaj lawm uas yog suav tias yog cov peev txheej txaus ntshai hauv ntau lub tebchaws. Txawm hais tias, 3G yuam kev nqis peev ntau dua los ntawm cov neeg siv xov tooj ntawm tes, nws tau muab cov ntaub ntawv ntau dua uas tsis tuaj yeem xa nrog GSM.
