检索结果-内蒙古大学图书馆

您好，读者！请登录

内蒙古大学图书馆

首页
概况
党建
资源
服务
科研支持
- 论文收录引用证明
- 科技查新
知识产权
档案馆
帮助

咨询与建议

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

您的常用邮箱：*

您的手机号码：*

问题描述：

当前已输入0个字，您还可以输入200个字

全部搜索
期刊论文
图书
学位论文
标准
纸本馆藏
外文资源发现
数据库导航
超星发现

高级检索

时间限定

出版年份：

文献类型

图书期刊文献学位论文多媒体

馆藏选择

电子馆藏纸本馆藏

核心期刊

全部期刊 SCI 收录期刊 SSCI 收录期刊 EI 收录期刊 CSCD 收录期刊 CSSCI 收录期刊

语言

中文英文

文献类型

期刊文献图书学位论文标准纸本馆藏

帮助

文字说明：

T=题名（书名、题名），A=作者（责任者），K=主题词，P=出版物名称，PU=出版社名称，O=机构（作者单位、学位授予单位、专利申请人），L=中图分类号，C=学科分类号，U=全部字段，Y=年（出版发行年、学位年度、标准发布年）

检索规则说明：

AND代表“并且”；OR代表“或者”；NOT代表“不包含”；(注意必须大写,运算符两边需空一格)

检索范例：

范例一：(K=图书馆学 OR K=情报学) AND A=范并思 AND Y=1982-2016
范例二：P=计算机应用与软件 AND (U=C++ OR U=Basic) NOT K=Visual AND Y=2011-2016

分类表

所选分类

>> <<

限定检索结果

文献类型

448 篇 会议
87 篇 期刊文献

馆藏范围

535 篇 电子文献
0 种 纸本馆藏

日期分布

学科分类号

154 篇 工学
- 97 篇 电气工程
- 88 篇 信息与通信工程
- 35 篇 电子科学与技术（可...
- 26 篇 计算机科学与技术...
- 24 篇 交通运输工程
- 12 篇 机械工程
- 11 篇 仪器科学与技术
- 6 篇 软件工程
- 2 篇 土木工程
- 2 篇 船舶与海洋工程
- 2 篇 航空宇航科学与技...
- 1 篇 材料科学与工程（可...
- 1 篇 控制科学与工程
- 1 篇 水利工程
10 篇 理学
- 4 篇 系统科学
- 3 篇 物理学
- 1 篇 数学
- 1 篇 天文学
- 1 篇 海洋科学
5 篇 管理学
- 5 篇 管理科学与工程(可...
3 篇 文学
- 3 篇 新闻传播学
2 篇 医学
- 2 篇 临床医学

主题

535 篇 direct-sequence ...
396 篇 multiaccess comm...
118 篇 fading
101 篇 multiple access ...
78 篇 detectors
76 篇 bit error rate
70 篇 multiuser detect...
55 篇 performance anal...
53 篇 power control
52 篇 interference
52 篇 interference can...
50 篇 multipath channe...
44 篇 bandwidth
43 篇 awgn
41 篇 spread spectrum ...
38 篇 base stations
37 篇 diversity recept...
36 篇 cdma mobile comm...
36 篇 frequency conver...
35 篇 matched filters

机构

8 篇 department of el...
5 篇 cetuc catholic u...
5 篇 centre for commu...
4 篇 department of el...
4 篇 institute for in...
4 篇 signal processin...
4 篇 department of el...
3 篇 isr-ist technica...
3 篇 school of electr...
3 篇 cetuc/puc-rio ri...
3 篇 school of electr...
3 篇 department of el...
3 篇 department of el...
3 篇 department of el...
3 篇 department of el...
3 篇 department of el...
3 篇 department of el...
3 篇 school of electr...
3 篇 national sun yat...
3 篇 department of ec...

作者

11 篇 j.k. tugnait
10 篇 f. adachi
7 篇 r. sampaio-neto
7 篇 r.c. de lamare
6 篇 l.b. milstein
6 篇 iickho song
6 篇 r. prasad
6 篇 m. sawahashi
5 篇 r. schober
5 篇 j.p. mcgeehan
5 篇 e.g. strom
5 篇 lie-liang yang
5 篇 yong huat chew
4 篇 s. shamai
4 篇 k. higuchi
4 篇 h.h. nguyen
4 篇 yang lie-liang
4 篇 t. ostman
4 篇 l. hanzo
4 篇 h.-j. zepernick

语言

511 篇 英文
19 篇 其他
4 篇 中文
1 篇 土耳其文

检索条件"主题词=direct-sequence code-division multiple access"

共 535 条记录，以下是241-250 订阅

全选清除本页清除全部题录导出标记到"检索档案"

详细简洁

排序：

Performance of uplink call admission control of DS-CDMA system under jamming in urban environment

Performance of uplink call admission control of DS-CDMA syst...

引用

MILCOM, Military Communications Conference

作者： J. Vesterinen Sven-Gustav Häggman Communications Laboratory Helsinki University of Technology

In this paper, the performance of different call admission control (CAC) algorithms of a direct sequence code division multiple access (DS-CDMA) system are compared under barrage jamming in an urban environment. Only the uplink circuit-switched speech traffic was inspected. The differences between the algorithms were compared through simulations and it was noticed that the performance of the CAC algorithms declined rapidly when jamming was increased. Especially the power based CAC algorithm turned out to be very sensitive to jamming.

关键词： Call admission control Multiaccess communication Jamming Interference Power control Bandwidth direct-sequence code-division multiple access Circuits Speech Communication system traffic control

来源：评论

学校读者我要写书评

暂无评论

Detecting active channels in an asynchronous DS-CDMA multiuser receiver

Detecting active channels in an asynchronous DS-CDMA multius...

引用

IEEE Conference on Vehicular Technology (VTC)

作者： R.M. Taylor J.D. Fite MITRE Corporation McLean VA USA

Nearly all the work in multiuser detection for direct sequence code division multiple access (DS-DCMA) assumes that the active channels are known. Previous attempts to solve the active channel detection problem assume short codes and use subspace methods that treat the multiple access interference (MAI) as noise. We consider forward link IS-95 asynchronous long code multiuser receivers and design an active channel detector that estimates the MAI as an intermediate step. The resulting algorithm subsumes multiuser detection in that we estimate symbols, amplitudes, and active channels jointly. The detector iteratively estimates and removes the MAI using an approach combining order statistics and constant false alarm rate thresholds on mixture densities. The performance of the new detector is compared to a conventional active channel detector which uses only the matched filter sufficient statistic. The new detector provides much higher probability of detection as a function of both capacity (number of active users) and SNR for cases of uniform and geometric power distributions. The new detector is shown to achieve nearly perfect probability of detection even in the near-far case with a moderately loaded system and just a few symbols.

关键词： Multiaccess communication Detectors multiple access interference Multiuser detection Probability direct-sequence code-division multiple access Active noise reduction Iterative algorithms Amplitude estimation Statistics

来源：评论

学校读者我要写书评

暂无评论

Improved bit error probability estimation for DS-CDMA downlink equalizer-based receivers with small spreading factors

Improved bit error probability estimation for DS-CDMA downli...

引用

International Conference on Telecommunications (ICT)

作者： E. Hardouin C. Laot Signal & Communications Department Eole Nationale Supérieure des Télécommunications de Bretagne Brest France

This paper provides insight into the statistical distribution of the interference at the output of receivers composed of a chip-rate linear transverse equalizer followed by a despreader for the downlink of direct-sequence code-division multiple access (DS-CDMA) systems with long scrambling sequences. It is shown that for small spreading factors, the probability density function (PDF) of the interference samples can be modeled accurately as a mixture of Gaussian PDFs. Each component of the mixture is associated with a particular realization of the scrambling sequence spanning the spread symbol to be retrieved. Based on this study, an analytical method allowing the computation of the bit error probability (BEP) for small spreading factors is derived. Numerical simulations show that the BEP estimation achieved by the proposed method is far more accurate than that obtained via the traditional Gaussian assumption on the interference statistics.

关键词： Error probability Estimation error Multiaccess communication Downlink Equalizers Interference Statistical distributions direct-sequence code-division multiple access Probability density function Numerical simulation

来源：评论

学校读者我要写书评

暂无评论

Throughput of RCPT hybrid ARQ for DS-CDMA with diversity reception and rake combining

Throughput of RCPT hybrid ARQ for DS-CDMA with diversity rec...

引用

IEEE Conference on Vehicular Technology (VTC)

作者： D. Garg F. Adachi Electrical and Communication Engineering Graduate School of Engineering University of Tohoku Sendai Japan

In this paper, we evaluate by computer simulations the throughput performance of rate compatible punctured turbo coded hybrid ARQ (RCPT HARQ) for direct sequence code division multiple access (DS-CDMA) with antenna diversity reception and rake combining in a frequency selective Rayleigh fading channel. The impact of a range of transmission system parameters and propagation parameters (viz.: the information sequence length, puncturing rate, spreading factor, number of diversity antennas, fading rate, and the power delay profile of the multipath channel) on the throughput is investigated. It is found that RCPT HARQ system has the highest throughput when minimum amount of redundancy bits is transmitted with each retransmission. In addition, the evaluations show that over a frequency selective fading channel, the throughput is almost insensitive to the information sequence length and the fading rate. It is also found that smaller spreading factor (SF) for a given chip rate gives a higher throughput in bps/Hz. Furthermore in the multi-user case, when the number of users is equal to SF, the total throughput for downlink is higher than that for uplink and is more or less independent of SF.

关键词： Diversity reception Throughput Automatic repeat request Multiaccess communication Fading Antennas and propagation Computer simulation Turbo codes direct-sequence code-division multiple access Frequency conversion

来源：评论

学校读者我要写书评

暂无评论

Coding across multicodes and time in CDMA systems for dispersive channels

Coding across multicodes and time in CDMA systems for disper...

引用

IEEE Conference on Wireless Communications and Networking

作者： J. Park J.-H. Lim S.B. Gelfand School of Electrical and Computer Engineering Purdue University West Lafayette IN USA Samsung Electronics Company Limited Suwon South Korea

When combining a multicode CDMA system with convolutional coding, two methods have been considered in the literature. In one method, coding is across time in each multicode channel while in the other the coding is across both multicodes and time. In this paper, a performance/complexity analysis of decoding metrics and trellis structures for the two schemes is carried out. It is shown that the latter scheme can exploit the multicode diversity inherent in convolutionally coded direct sequence code division multiple access (DS-CDMA) systems which employ minimum squared error (MMSE) multiuser detectors. In particular, when the MMSE detector provides sufficiently different signal-to-reference ratios (SIRs) for the multicode channels, coding across multicodes and time can obtain significant performance gain over across time, with nearly the same decoding complexity.

关键词： Multiaccess communication Dispersion Convolutional codes Convolution Decoding Detectors Performance analysis Diversity reception direct-sequence code-division multiple access Performance gain

来源：评论

学校读者我要写书评

暂无评论

Capacity and performance gains through temporal and spatial oversampling

Capacity and performance gains through temporal and spatial ...

引用

IEEE Conference on Vehicular Technology (VTC)

作者： O.H. Koymen T.H. Meng Center for Integrated Systems University of Stanford Stanford CA USA

In this work we present simulation results on the capacity and performance gains attainable by oversampling at the receiver in the temporal and spatial domains. The study assumes a downlink direct sequence code division multiple access (CDMA) system with a linear receiver. Oversampling in the temporal domain refers to sampling at a rate higher than the chip-rate. Oversampling in the spatial domain refers to multiple receiver antennas. The simulations results verify various aspects of our theoretical results including the dimensional resolution of inter-symbol interference (ISI) through spatial oversampling and the utilization of the bandwidth expansion for capacity gains through temporal oversampling. We quantify the performance gains by illustrating increases in system dimensionality and providing a bit error rate (BER) metric.

关键词： Performance gain Bit error rate Downlink direct-sequence code-division multiple access Multiaccess communication Sampling methods Receiving antennas Spatial resolution Intersymbol interference Bandwidth

来源：评论

学校读者我要写书评

暂无评论

On the improvement of blind MOE detector via a posteriori adaptation and adaptive step-size

On the improvement of blind MOE detector via a posteriori ad...

引用

IEEE International Symposium on Circuits and Systems (ISCAS)

作者： S. Pampichai P. Sirisuk Department of Electronic Engineering Mahanakom University of Technology Thailand Department of Electronic Engineering Mahanakom University of Technology Bangkok Thailand

This paper presents a blind multiuser detector for direct sequence-code division multiple access (DS-CDMA) systems. The adaptation of the proposed detector is based upon the adaptive step-size Minimum Output Energy (MOE) algorithm, which can achieve improvements over the original MOE detector. In this work, we develop a posteriori adaptation for the adaptive step-size MOE detector to further improve performance of the technique. Simulations show that the proposed detector yields significant improvements over the existing techniques especially in dynamic environments where the number of interferers are time-varying.

关键词： Detectors Multiaccess communication Multiuser detection Least squares approximation Adaptive filters multiple access interference Adaptive algorithm Satellites direct-sequence code-division multiple access Timing

来源：评论

学校读者我要写书评

暂无评论

A linear smoothing method for enhancing near-far resistance of CDMA detectors

A linear smoothing method for enhancing near-far resistance ...

引用

International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： Xiaodong Yue H.H. Fan Department of ECECS University of Cincinnati Cincinnati OH USA

The near-far problem in a multiuser setting places fundamental limitations on the performance of CDMA communication systems. In the past, significant effort has focused on designing practical, and hence suboptimum, detectors to combat multiple access interference (MAI). However, the optimality in near-far resistance is generally lost with suboptimum detectors. One method which can enhance the near-far resistance of suboptimum detectors under multipath channels is presented. The proposed method is able to overcome the shortcomings of existing methods. Computer simulations confirm the theoretical findings.

关键词： Smoothing methods Multiaccess communication Detectors multiple access interference Computer simulation Computational modeling direct-sequence code-division multiple access code division multiplexing Wireless communication Frequency

来源：评论

学校读者我要写书评

暂无评论

Noncoherent continuous-phase modulation for DS-CDMA

Noncoherent continuous-phase modulation for DS-CDMA

引用

IEEE International Conference on Communications (ICC)

作者： L.H.-J. Lampe R. Tzschoppe J.B. Huber R. Schober Institute for Information Transmission University of Erlangen Nuremberg Germany Department of Electrical & Computer Eng University of British Columbia Canada

The combination of continuous phase modulation (CPM) with direct-sequence code-division multiple access (DS-CDMA) for multiuser transmission over the additive white Gaussian noise channel is discussed. Concentrating on the important special case of generalized minimum-shift keying, particularly simple receiver structures are obtained. To emphasize on low complexity, noncoherent reception is proposed and appropriate transmitter and receiver designs are provided. The application of reduced-state noncoherent sequence detection and noncoherent filter adaptation ensures high power efficiency and robustness against channel phase variations. Simulation results confirm that the chosen approach of CPM for DS-CDMA achieves high performance with very moderate complexity.

关键词： Multiaccess communication Transmitters Phase detection Pulse modulation AWGN Phase modulation Continuous phase modulation direct-sequence code-division multiple access Additive white noise Filters

来源：评论

学校读者我要写书评

暂无评论

Narrowband interference suppression in CDMA using random walk tracking algorithm

Narrowband interference suppression in CDMA using random wal...

引用

International Conference on Information, Communications and Signal Processing

作者： S.M. Saberali H. Amindavar Department of Electrical Engineering Amirkabir University of Technology슠 Tehran Iran Iran Telecommunication Research Center Iran

It has been shown that the narrowband interference suppression capability of a direct sequence spread spectrum system can be enhanced considerably by processing the received signal via a prediction error filter prior to correlating it with the pseudo noise (PN) sequence. In this paper we present a new method to suppress narrowband interference in direct sequence code division multiple access (DS-CDMA) systems. The proposed scheme is a nonlinear predictor that consists of a quantizer and random walk tracking algorithm. This algorithm is used for tracking a random walk in white Gaussian noise. This algorithm has two important features. First, this algorithm does not require the estimation of the interference statistics. Second, it does not require training sequences. Computer simulation results show that the proposed approach has better performance than conventional linear filtering.

关键词： Narrowband Interference suppression Multiaccess communication Spread spectrum communication Signal processing Nonlinear filters direct-sequence code-division multiple access Gaussian noise Statistics Computer simulation

来源：评论

学校读者我要写书评

暂无评论

没有更多数据了...

全选清除本页清除全部题录导出标记到“检索档案”

共54页 << < 21 22 23 24 25 26 27 28 29 30 > >>

检索报告对象比较合并检索0

隐藏清空

合并搜索

回到顶部

执行限定条件

内容：

评分：

请选择保存的检索档案：

请选择收藏分类：

订阅名称：

通借通还

温馨提示：

图书名称：

借书校区：

取书校区：

手机号码：

邮箱地址：

一卡通帐号：

电话和邮箱必须正确填写，我们会与您联系确认。

联系人：

所在院系：

联系邮箱：

联系电话：

内蒙古自治区呼和浩特市赛罕区大学西街235号邮编: 010021

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：