检索结果-内蒙古大学图书馆

IEEE 79th Vehicular Technology Conference (VTC-Spring)

作者： Manolakis, Konstantinos Gutierrez-Estevez, M. A. Jungnickel, Volker Tech Univ Berlin Dept Telecommun Syst Berlin Germany Fraunhofer Heinrich Hertz Inst Berlin Germany

ISBN: (纸本)9781479944828

Link adaptation is recognized as a powerful technique for enhancing spectral efficiency over wireless channels. While its theoretical aspects are well understood, it is not clear yet how to practically deal with limited feedback. In this paper, we study a frequency-selective link adaptation scheme for orthogonal frequency division multiplexing (OFDM). The modulation order is adjusted per resource block (smallest time-frequency unit assigned to a user), while a joint coding rate is used for all variable-length codewords, comprising resource blocks with different modulations. In order to meet the required coding rate, adaptive puncturing is applied after a fixed-rate turbo encoder. Link adaptation is guided by an effective signal-to-noise ratio (SNR), which is calculated over several subcarriers by a mapping function. 3GPP LTE compliant link-layer simulations were performed for optimizing the SNR interface so that the spectral efficiency is maximized under a codeword error rate constraint and tradeoffs between feedback savings and spectral efficiency losses were elaborated. The result is a thoroughly tested link-layer abstraction for 3GPP LTE including adaptive modulation and bit-interleaved coding that can be also used for system-level simulations towards future mobile radio systems.

关键词： 3G mobile communication Long Term Evolution OFDM modulation adaptive modulation interleaved codes telecommunication links turbo codes variable length codes wireless channels 3GPP LTE systems OFDM SNR bit-interleaved coding codeword error rate frequency-selective link adaptation scheme joint coding rate mobile radio systems orthogonal frequency division multiplexing signal-to-noise ratio spectral efficiency turbo coding variable-length codewords Adaptation models Channel coding Fading Modulation Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Random Interleaver Design in turbo coding for Digital Magnetic Recording Channel

Random Interleaver Design in Turbo Coding for Digital Magnet...

引用

36th International Convention on Information and Communication Technology, Electronics and Microelectronics (MIPRO)

作者： Stancescu, St. Sandu, C. Univ Politehn Bucuresti Bucharest Romania

ISBN: (纸本)9789532330762

turbo codes interleaver logic is analyzed in Digital Magnetic Recording (DMR) Partial Response (PR) channels environment. The performances of turbo encoding/decoding process are estimated, in the presence of appropriate DMR noise, generally a particulate noise, manifested as burst errors of various intensities and dimensions. Depending of interleaver, turbo code performance (Bit Error Rate BER) is estimated, in presence of noise, over variations with its parameters. Optimal code length and structures design recommendations are obtained, related to required recording densities and Signal Noise Ratio (SNR) ranges.

关键词： turbo coding interleaver magnetic recording

来源：评论

学校读者我要写书评

暂无评论

Adaptive channel equalization in WCDMA downlink with turbo coding

Adaptive channel equalization in WCDMA downlink with turbo c...

引用

13th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications

作者： Hooli, K Drajic, D Tujkovic, D Oulu Univ Ctr Wireless Commun FIN-90014 Oulu Finland

ISBN: (纸本)0780375890

Receivers based on channel equalization have proven to be one of the most promising candidates for terminal receivers in wideband code-division multiple-access (WCDMA) downlink. The channel equalizers provide multiple access interference (MAI) suppression, and thus ensure adequate receiver performance even with a high number of active users. However, the performance improvement provided by the equalizers in conjunction with a powerful forward error control (FEC) coding has been unclear. In this paper, the performance of adaptive equalizers is numerically evaluated with 1/3-rate turbo coding, and compared to the performance of the conventional Rake receiver. The numerical results show significant performance improvement ever the conventional Rake receiver in a Rayleigh fading multipath channel.

关键词： WCDMA downlink multiple access interference equalization turbo coding

来源：评论

学校读者我要写书评

暂无评论

turbo-DC-FSK : Joint turbo coding and FSK-Based Modulation for Visible Light Communications

Turbo-DC-FSK : Joint Turbo Coding and FSK-Based Modulation f...

引用

Joint Conference of European Conference on Networks and Communications (EuCNC) and 6G Summit (6G Summit)

作者： Miqueu, Paul Khan, Muhammad Jehangir Le Guennec, Yannis Ros, Laurent Univ Grenoble Alpes GIPSA Lab CNRS Grenoble INP Grenoble France

ISBN: (纸本)9781665498715

In this article, we propose and analyze a joint turbo coding and DC-FSK modulation scheme (turbo-DC-FSK) dedicated to visible light communications (VLC). This method is an adaptation to satisfy the VLC requirements of the turbo-FSK technique initially developed for the long range low power Radio-Frequency context in CEA-LETI (during the PhD of Yoann Roth, in collaboration with Gipsa-lab). It requires a change in the modulation alphabet generation to get unipolar real baseband signal instead of a complex bipolar one. We propose, in this paper, to deal with real Discrete Cosine Transform (DCT) instead of complex Discrete Fourier Transform (DFT) to generate the Frequency Shift Keying (FSK) modulation alphabet. We, then, add a constant component (DC) to make the signal unipolar and positive. This scheme involves a FSK-based modulation at the transmitter side, i.e. DC-FSK, and a turbo-decoder scheme at the receiver side, i.e. Bahl, Cocke, Jelinek and Raviv (BCJR) algorithm. Simulation results confirm that turbo-DC-FSK can achieve around 4 dB energy gain over regular VLC state-of-the-art DC-FSK modulation at a BER = 10(-4) ans at same spectral efficiency. Using lambda parallel branches, a desired balance between energy efficiency and spectral efficiency is achieved.

关键词： VLC turbo coding FSK modulation Internet of Things

来源：评论

学校读者我要写书评

暂无评论

Performance of STBC-MC-CDMA system based on complex wavelet packet and turbo coding

引用

Journal of Southeast University(English Edition) 2005年第4期21卷 398-404页

作者：虞湘宾毕光国南京航空航天大学信息与通信工程博士后流动站南京210016 东南大学移动通信国家重点实验室南京210096

On the basis of analyzing the principle of the space-time coding technique and the multi-carrier code division multiple access （MC-CDMA） technique, adopting the turbo codes as channel coding and the optimized complex wavelet packet as multi-carrier modulation, a novel space-time block coded the MC-CDMA system based on complex wavelet packet and turbo coding is proposed, and the system bit error rate （BER） performance in the Rayleigh fading channel is investigated. The system can make full use of space-time block codes＇ transmit diversity and turbo codes＇ good ability against fading channel to improve the BER performance significantly, and it can also avoid the decrease of spectrum efficiency of conventional MC-CDMA due to inserting cyclic prefix （CP） by utilizing superior characteristics of the optimized complex wavelet packet. Simulation results show that the proposed space-time block coded MC-CDMA system based on the complex wavelet packet performs better than the conventional space-time block coded MC-CDMA （STBC-MC-CDMA） system, and slightly outperforms the STBC-MC-CDMA with CP. Moreover, the application of the space-time block coding technique concatenated with turbo codes strengthens the system ability to combat various interferences in fading channel further.

关键词： multi-carrier technique complex wavelet packet space-time block code code division multiple access turbo coding

来源：评论

学校读者我要写书评

暂无评论

Random Binning and turbo Source coding for Lossless Compression of Memoryless Sources

Random Binning and Turbo Source Coding for Lossless Compress...

引用

64th IEEE Vehicular Technology Conference

作者： Haghighat, Javad Hamouda, Walaa Soleymani, M. Reza Concordia Univ Dept Elect & Comp Engn Montreal PQ H3G 1M8 Canada

ISBN: (纸本)9781424400621

We propose a tree structured variable length random binning scheme that enables an error correcting code to act as a source code. The existing source coding schemes based on turbo codes, low density parity check codes, and repeat accumulate codes can be regarded as practical implementations of this random binning scheme. We investigate the performance of lossless turbo source coding relative to the proposed tree structured random binning scheme. Our numerical results show that the compression rate achieved by lossless turbo source coding is far from the tree structured random binning bound. In that, we suggest improvements to enable short block length turbo source codes to achieve compression rates close to the tree structured random binning bound.

关键词： random binning turbo coding entropy

来源：评论

学校读者我要写书评

暂无评论

Performance of a turbo coded multicarrier DS/CDMA system with nonuniform repetition coding

引用

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2001年第9期19卷 1764-1774页

作者： Kim, YH Milstein, LB Song, I ETRI Radio & Broadcasting Technol Lab Yuseong Gu Taejon 305350 South Korea Univ Calif San Diego Dept Elect & Comp Engn San Diego CA 92093 USA Korea Adv Inst Sci & Technol Dept Elect Engn & Comp Sci Yuseong Gu Taejon 305701 South Korea

This paper presents a turbo coded multicarrier direct sequence code division multiple access (DS/CDMA) system, where the outputs of a turbo encoder are repetition coded at multiple rates and transmitted in parallel over a number of subchannels. A performance bound useful in the so-called error floor region is obtained for Rayleigh fading channels when different diversity orders are given to each turbo code symbol. Simulation results are also provided for the low signal-to-noise ratio (SNR) region where the bound is not applicable. It is observed that the error floor can be lowered, with some performance loss in the low SNR region, by applying nonuniform repetition coding to the turbo code symbols.

关键词： multicarrier DS/CDMA nonuniform repetition coding turbo coding

来源：评论

学校读者我要写书评

暂无评论

Pre-decorrelation in turbo-coded DS-CDMA system using space-time coding over fading channels

Pre-decorrelation in turbo-coded DS-CDMA system using space-...

引用

25th National Radio Science Conference

作者： Al-Hosarey, Farid S. Elazm, Atef A. Madkour, Mohamed F. Faculty of Electronic Engineering Menoufia University Egypt Faculty of Engineering Alexandria University Egypt

ISBN: (纸本)9789775031952

In this paper, we deal with the Multiple Access Interference (MAI) suppression problem in turbo coded Space-Time Block Coded (STBC) Direct Sequence Code-Division Multiple-Access (DS-CDMA) systems. In the proposed system, we preprocess (decorrelate) the coded bits in the transmitter side instead of using a decorrelating detector in the receiver. Using this method, the base station can perform decorrelation before transmissions and the mobile unit uses the conventional receiver achieving approximately the performance of the decorrelating detector. Performance comparison is made between this method and existing decorrelating detector in fading channels. This paper also investigates the performance improvement due to channel coding. Performance comparison between turbo coded STBC DS-CDMA systems employing different interleaver sizes and Soft-Decision Convolutional Codes (SD-CC) is also provided.

关键词： CDMA multi-user detection transmit diversity space-time block coding turbo coding

来源：评论

学校读者我要写书评

暂无评论

CFB-AES-turbo: Joint Encryption and Channel coding for Secure Satellite Data Transmission

CFB-AES-TURBO: Joint Encryption and Channel Coding for Secur...

引用

IEEE International Conference on Communications (IEEE ICC)

作者： Jeon, Suhyeon Choi, Jihwan P. DGIST Dept Informat & Commun Engn Daegu South Korea

ISBN: (纸本)9781538680889

As the advanced satellite network can serve extremely diverse information data to different types of users, it is of a vital interest to achieve data security using encryption over satellite channels. However, because the avalanche effect makes encryption techniques vulnerable to bit errors in the wireless channel, a more powerful encryption technique is required. In this paper, we propose a novel method of joint encryption and channel coding, called CFB-AES-turbo, by combining advanced encryption standard (AES) encryption and turbo coding. As we introduce turbo coding in the cipher feedback (CFB) mode with AES, our scheme can protect bits and also correct bit errors. We control system parameters of the encryption block size and the code rate, tailored to the channel state information (CSI). As a result, we can achieve processing time gains, security enhancement, and bit error rate (BER) performance improvement at the same time.

关键词： Satellite communications Security Channel coding Advanced encryption standard turbo coding

来源：评论

学校读者我要写书评

暂无评论

Neural Crypto-coding as DES: turbo over Land Mobile Satellite (LMS) Channel 3

Neural Crypto-Coding as DES: Turbo over Land Mobile Satellit...

引用

3rd International Conference on Communications and Signal Processing (ICCSP)

作者： Khanai, Rajashri Kulkarni, G. H. Torse, Dattaprasad A. Gogte Inst Technol Dept Elect & Elect Engn Belgaum Karnataka India Jain Coll Engn Dept Elect & Elect Engn Belgaum Karnataka India Visvesvaraya Technol Univ Belgaum Dept Elect Engn Belgaum Karnataka India

ISBN: (纸本)9781479933587

Modern wireless communications have increased requirements for reliable communication with significant security mechanisms. In this paper cryptography and error correction coding is combined in a single step known as "Crypto-coding". The focus is on the application of neural networks to Crypto-coding. This approach provides data security for reliable transmission as encryption and error correction takes place in a single step. The computational costs and increase efficiency, mainly in practical system performance is evaluated over Land Mobile Satellite (LMS) channel. We are combining Data Encryption Standard (DES) and turbo coding in a single step to significantly reduce realizations. A number of experimental studies show applicability of the technique to a selected set of areas in cryptography and error correction coding. Simulation results show that the BER performance of the neural Crypto-coding is close to the Crypto-coding, for data length equal to 1024 bits, and achieves a BER of about 4 x 10(-5) at an SNR of 10 dB. The proposed algorithms are well suited for implementation on a VLSI-platform.

关键词： Convolutional code Data Encryption Standard Interleavers Land Mobile Satellite Channel Neural Crypto-coding turbo coding

来源：评论

学校读者我要写书评

暂无评论

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：

请选择收藏分类：

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

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：