英语翻译uAbstract-This paper analyzes the benefits of using a decision feedback equalizer (DFE) in the indoor radio environment and examines the results of performance predictions for different channel modelings.It is found that a QPSK/DFE modem

英语翻译uAbstract-This paper analyzes the benefits of using a decision feedback equalizer (DFE) in the indoor radio environment and examines the results of performance predictions for different channel modelings.It is found that a QPSK/DFE modem
英语翻译
u
Abstract-This paper analyzes the benefits of using a decision feedback equalizer (DFE) in the indoor radio environment and examines the results of performance predictions for different channel modelings.It is found that a QPSK/DFE modem with second-order diversity can operate at a data rate which is an order of magnitude higher than a QPSK modem without equalization.A given set of measured profiles of the channel impulse response is interpreted using continuous and discrete channel models.The continuous channel model is represented by the delay power spectrum and the discrete channel model by the envelope delay power spectrum and the arrival rate of the paths.The sensitivity of the performance to the shape of the delay power spectrum,the shape of the envelope delay power spectrum,and the arrival rate of the paths is analyzed.
INTRODUCTION
TH IS paper investigates high speed (wideband) data transmission over the indoor radio channel using adaptive equalization and compares the results to those obtained over an unequalized channel.The existing performance predictions for various communication techniques are either based on a continuous or a discrete channel model.This paper compares performance predictions for both channel models and justifies the differences.To avoid expensive installation and relocation costs and to provide portability to various pieces of equipment,the concept of wireless indoor communication networks suggests itself as a replacement for wired data communication networks.Recently,both infrared and radio frequency communications have been examined for this purpose [l],[2].Research in radio frequency communications is concentrated on channel measurements [3],[4]and transmission problems both for spread spectrum [5],[6] and standard modulation techniques [7].Communication network applications demand very high data rates,but the data rate in indoor channels is bounded due to multipath and fading [7],[SI.To improve the data rate,performance enhancement techniques such as external
diversity,coding,and spread spectrum have been
studied [5]-[7].Another method of improving the data
rate is to use adaptive equalization.The advantage of
adaptive equalization over coding and spread spectrum is
that a modem with adaptive equalization provides high
data rates without any loss in bandwidth efficiency.The
decision feedback equalizer (DFE) has been shown to improve
the performance of digital communication systems
over various fading multipath channels such as troposcatter
[9],HF [lo],and microwave line-of-sight [ 111,[ 121.
This paper shows that the use of an adaptive DFE in the
receiver in indoor channels can result in high-speed transmission
in which the bandwidth of the transmitted signal
is about the same as the coherent bandwidth of the channel.
This data rate is an order of magnitude higher than
similar systems with no equalizer.
The existing performance predictions for narrowband

英语翻译uAbstract-This paper analyzes the benefits of using a decision feedback equalizer (DFE) in the indoor radio environment and examines the results of performance predictions for different channel modelings.It is found that a QPSK/DFE modem
u
摘要-这一张纸分析使用户内的收音机环境的一个决定回应使相等的东西 (DFE) 的利益而且为不同的频道模型调查表现预测的结果.以下被发现：和第二次序的不同 QPSK/DFE 调制解调器能在比没有均等的一个 QPSK 调制解调器更高地是一个大小的次序的数据率操作.频道的一给定组标准描绘推动回应被解释使用连续的和不连续的频道模型.连续的频道模型被延迟力量光谱和不连续的频道表现模型被路径的信封延迟力量光谱和抵达率.对延迟的形状的表现的敏感使光谱,信封延迟力量光谱的形状有力量,而且路径的抵达率被分析.
介绍
TH 是调查的纸,在使用适合的均等,而且比较结果和那些的户内的收音机频道上的高速 (宽波带) 数据传输遍及一个被频道不相等的获得了.对于各种不同的沟通技术的现有表现预测是或基于连续或一个不连续的频道模型.这一张纸比较表现预测为两者的频道模型而且证明不同.避免贵的安装和再布置费用和提供可携带给各种不同个的设备,无线户内的沟通网络的观念为以线加强的数据沟通网络意味着它本身如一个替换.最近,红外线的和无线电电波沟通已经为这目的 [l] 被调查,[2].无线电电波沟通的研究被专注于频道测量 [3],[4] 和传输问题两者都对于扩延的光谱 [5],[6] 和标准调音技术 [7].网络申请要求非常高的数据率,但是由于多路径户内的频道的数据率被跳跃而且时尚 [7],[SI.改善如此的如外部的数据率,表现提高技术
不同,编码,和传布光谱是
学习 [5]-[7].改良数据的另一个方法
比率将使用适合的均等.利益
适合的均等过度编码和传布光谱是
和适合的均等一个调制解调器提供高度
没有带宽效率的任何失败,数据评估.那
决定回应使相等的东西 (DFE) 已经被显示改善
数传沟通制度的表现
在各种不同的时尚多路径之上引导如此的如 troposcatter
[9],HF[瞧!],和微波视线 [111,[121.
这一张纸表示适合 DFE 的使用在那
户内的频道的接收器能造成高速的传输
在哪一个被传输的信号的带宽
是差不多的如频道的互相密合着带宽.
这数据率是一个大小的次序比较高的超过
和没有使相等的东西相似的系统.
为 narrowband 的现有表现预测

那么长才二十分～？