Definitions and brief explanations
2G: GSM (9.6 kbps) Global System for Mobile Communications .
European digital standard using frequencies of 900 and 1800 MHz.
GSM is the leading mobile system users.
2.5G: GPRS (40-56 kbps) Global Packet Radio Service.
Evolution of GSM mobile phone standard that enables data transfers packages, as on the Internet.
2.75G: EDGE (100 to 247 kbit / s) Acronym for Enhanced Data GSM Environment.
Evolution of GPRS mobile telephony standard, it offers a maximum throughput of 247 kbps, which enables mobile TV but not the video.
3G: UMTS (DL: 144 to 384 kbit / s & UP: 128Kbit / s) Universal Mobile Telecommunications System (UMTS)
system called 3G operators. It is based on W-CDMA. (Peaks at 2Mbit / s in very specific conditions). Allows in addition to EDGE and a video flow a little more important.
3.5G: HSDPA (DL: 900 kbit / s to 14.4 Mbit / s & UL: 384kbit / s) High Speed Downlink Packet Access.
Evolution of 3G also called 3G +
Speaking "technical", there are two modules for HSDPA QPSK: that used by Orange and SFR in 2006 to 1.8 Mbit / s theoretical (for a single user on a base station: this is never the case !!!). It's HSDPA 16QAM 12modulation category: that should be used in late 2007, allowing theoretical speeds of 3.6 Mbps. HSDPA is the Category 5 or 6.
0 comments:
Post a Comment