22 Apr 2008

主流 3G 标准线索

目前主流的 3G 标准主要有三个:
* UMTS,于 GSM 兼容,固定速率 2Mbps,低速 384 kbps,快速移动 144kbps
* CDMA2000 已经有比较成熟的商用了。
* TD-SCMA 384kbps

三个标准的发展线索:
* UMTS WCDMA -> HSDPA -> HSUPA -> HSPA+ -> LTE
* CDMA2000 -> EV-DO Rev.0 -> Rev.A -> Rev.B -> UMB
* TD-SCDMA

其中 LTE/UMB 是未来的 4G 标准。GSM 是 2G,GPRS 2.5G,EGDE 2.75G

3G/4G 的竞争者:
* WiFi: 802.11a/b/g/n 已经有了广泛应用
* WiMax: 802.16 发展了移动版,可以在不同的热点间切换,似乎已经有内置 WiMax 的笔记本了
* 802.20:还是纸上谈兵,如果在谈的话
* 移动电视网络/IPTV: 独立的芯片,独立的网络,将移动电视从传统移动网络中剥离

WiFi/WiMax/802.20 可以提供快速的移动网络,并借助 VoIP 和 3G/4G 竞争。

--
每一个不曾起舞的日子都是对生命的辜负。
Gmail/Gtalk: jick.nan@gmail.com

3 comments:

  1. 据说混3G的人都特别有钱,哈
    换个工作可能会有大把大把的钞票吧

    ReplyDelete
  2. Chen Sir 联想丰富 :P

    不是想混 3G,只是了解一下最新发展,免得落伍 :-)

    ReplyDelete
  3. n English class, one girl Cheap WoW Gold said never buy WoW Gold give up when discussing. It just reminded me wow goldsomething about myself.WoW Gold Maybe it is wow power leveling something about love.WoW Gold My love, which began on July 3rd of WoW Gold 2005 and finished on August wow leveling 23rd of 2008, taught me many things. wow leveling It is not a pleasant world of warcraft power leveling thing to look back on world of warcraft power leveling that. But I know I world of warcraft power leveling must learn something from it,world of warcraft leveling no matter what it is, world of warcraft leveling happiness or sorrow.Our love did not go on so smoothly and we went through many things

    ReplyDelete