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标题: 802.11a中，一个基本概念有点迷惑 [查看完整版帖子] [打印本页]

时间: 2013-12-10 18:52

作者: sun3596209 标题: 802.11a中，一个基本概念有点迷惑

上图截取自《802.11无线网络权威指南+第二版》第十三章
下图截图自《下一代无线局域网 802.11n的吞吐率、强健性和可靠性》第四章

这两章都是介绍802.11a PLCP帧的章节，可是关于符号时间却完全不一样。求高手解答一下，谢谢

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时间: 2013-12-11 18:50

作者: burtliu

preamble symbols include two part STF(short training field) and LTF(long training field), STF includes 10 symbols (this is not ofdm symbols)every symbol is 0.8us, so it's 10x0.8 = 8us, LTF includes two OFDM symbols, every OFDM symbols is 0.8+3.2 = 4 us, so LTF is 4x2 = 8 us, it means the whole preamble is 12 symbols (0.8x10 + (0.8+3.2)x2)= 16us.

signal field is one OFDM symbols so it's 0.8+3.2 = 4us.

时间: 2013-12-11 19:00

作者: sun3596209

burtliu 发表于 2013-12-11 18:50
preamble symbols include two part STF(short training field) and LTF(long training field), STF includ ...

good，3Q

另外我还有一个问题，11a中通过在符号间插入一些padding bit，以使符号过度平滑。这些padding bit，是不是就是所谓的STF？？

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