Upgrade Mobile

#معلومة
#Band 900 is the default band for #GSM
#Band 2100 is the default band for #UMTS
#Band 1800 is the default band for #LTE
but due to band limitation and also congestion .. all generation can work in the same band of another band (e. g. both GSM & 3G can work in band 900)
The process to allow 2 generation (2G & 3G) or (2G&4G) work in the same band of the same operator is called Refarming
For example if you have 2G work in band 900 then u have license to operate 3G and u want to operate it in band 900 .. then u have to make Refarming for ur licensed 900 channels to allow both 2G & 3G in same band
As for users equipments it is depends on the model and the region where the device has been released.   Many operators can get license in the same band toll the band become full .. in KSA band 900  is licensed for STC & Mobily .. Zain has license in the Extended GSM (EGSM)...

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