移动通讯标准-白红宇

移动通讯标准

阅读量：175 次

发布时间：2019-02-28

本文共 443 字，大约阅读时间需要 1 分钟。

GSM	2G（二代通信技术）。只能打电话
GPRS	2.5G。GSM上发展起来的移动数据业务，比如上网。
EDGE	2.75G。比GPRS速度更快一些，目前的移动2G上网都是这个标准。
WCDMA	3G。
HSDPA	3.5G。高速下行分组数据接入技术。在下行链路上能够实现高达7.2M 和 14.4Mbit/s的速率。
HSUPA	3.5G。高速上行分组数据接入技术。：在上行链路中能够实现高达5.76Mbit/s的速度。
HSPA+	3.75G。（H+信号），增强型高速分组接入。上行速率达：5.76M，下行速率达：21M或28M。
TDD LTE	4G。时分双工。理论下行速度为100Mbps。
FDD LTE	4G。频分双工。理论下行速度为150Mbps。

GSM有四个频段(850,900,1800,1900)，国内使用的是GSM900， GSM1800。

WCDMA有四个Band(1/2/5/8)，（850/900/1900/2100MHz），国内使用BAND1频段。

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