作业帮 > 英语 > 作业

英语翻译14.1 IEEE 802.15.4 Modulation FormatThis section is mean

来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:英语作业 时间:2024/04/29 17:03:55
英语翻译
14.1 IEEE 802.15.4 Modulation Format
This section is meant as an introduction to
the 2.4 GHz direct sequence spread
spectrum (DSSS) RF modulation format
defined in IEEE 802.15.4.For a complete
description,please refer to [1].
The modulation and spreading functions
are illustrated at block level in Figure 37
[1].Each byte is divided into two symbols,
4 bits each.The least significant symbol istransmitted first.For multi-byte fields,the
least significant byte is transmitted first.
Each symbol is mapped to one out of 16
pseudo-random sequences,32 chips
each.The symbol to chip mapping is
shown in Table 42.The chip sequence is
then transmitted at 2 MChips/s,with the
least significant chip (C0) transmitted first
for each symbol.The modulation format is Offset –
Quadrature Phase Shift Keying (O-QPSK)
with half-sine chip shaping.This is
equivalent to MSK modulation.Each chipis shaped as a half-sine,transmitted
alternately in the I and Q channels with
one half chip period offset.This is
illustrated for the zero-symbol in Figure 38.
英语翻译14.1 IEEE 802.15.4 Modulation FormatThis section is mean
14.1 IEEE 802.15.4模块化格式
This部分意味作为介绍
the 2.4 GHz直接顺序传播
spectrum (DSSS) RF模块化格式 在IEEE 802.15.4的defined.为完全
description,请参见[1].
The模块化和弥漫函数
are被说明在块水平在表37
[1].每个字节被划分成二个标志,
4位其中每一.首先istransmitted的最少重大标志.为多字节领域,
least重大字节首先被传送.
Each标志被映射到一个出于16
pseudo-random序列,32块芯片
each.对芯片映射的标志是
shown在表42.芯片序列是
then被传送在2 MChips/s,与
least重大芯片(C0)首先传送了
for每个标志.模块化格式是垂距–
Quadrature相移键控(O-QPSK)
with一半正弦芯片塑造.这是 对MSK模块化的equivalent.每作为一半正弦被塑造的chipis,被传送的在I和Q渠道的alternately与
one半芯片期间垂距.这是 零标志的illustrated在表38.