英语翻译14.1 IEEE 802.15.4 Modulation FormatThis section is meant as an introduction tothe 2.4 GHz direct sequence spreadspectrum (DSSS) RF modulation formatdefined in IEEE 802.15.4.For a completedescription,please refer to [1].The modulation and

英语翻译14.1 IEEE 802.15.4 Modulation FormatThis section is meant as an introduction tothe 2.4 GHz direct sequence spreadspectrum (DSSS) RF modulation formatdefined in IEEE 802.15.4.For a completedescription,please refer to [1].The modulation and
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 meant as an introduction tothe 2.4 GHz direct sequence spreadspectrum (DSSS) RF modulation formatdefined in IEEE 802.15.4.For a completedescription,please refer to [1].The modulation and
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.