检索结果-内蒙古大学图书馆

11th IEEE International Conference on Electronics, Circuits and Systems

作者： Rahamim, Y Freedman, A Reichman, A Tel Aviv Univ Sch Elect Engn IL-69978 Tel Aviv Israel

ISBN: (纸本)0780387155

The invention of turbo Codes has manifested the ability of communications systems to operate at very low signal to noise ratio, very close to the theoretical Shannon capacity limit. However, synchronization of turbo-coded signals operating in low SNR conditions may be difficult, especially for short packet transmission. This paper proposes the Maximum-Likelihood Iterative-Tentative-Decision-Directed (ML-ITTD) circuit for using the tentative decisions produced by the turbo decoder to improve the carrier synchronization in turbo coded short packets communication systems. The ML-ITDD method operates iteratively and jointly with the turbo decoder, enhancing both the turbo-decoder and the synchronization performance. The ML-ITDD method has been shown by simulation to significantly increase the allowed initial frequency and phase uncertainty region, thus allowing the use of very short training sequences for initial carrier synchronization.

关键词： phase and frequency synchronization turbo coding packet radio

来源：评论

学校读者我要写书评

暂无评论

Sorting Methods Used in Parallel turbo Decoding for LTE Systems 12

Sorting Methods Used in Parallel Turbo Decoding for LTE Syst...

引用

2015 International Symposium on Signals, Circuits and Systems (ISSCS)

作者： Anghel, Cristian Stanciu, Cristian Paleologu, Constantin Univ Politehn Bucuresti Telecommun Dept Bucharest Romania

ISBN: (纸本)9781467374880

This paper presents the main methods used for sorting when parallel decoding architecture is used for Long Term Evolution (LTE) systems turbo codes. Usually, the parallelization factor N represents the number of required interleavers. We propose a decoding architecture with only one Quadratic Permutation Polynomial (QPP) interleaver. All the interleaved addresses are placed on the same memory location, as a consequence of QPP interleaver algebraic properties, but sorting is needed before sending the correct data to each decoder unit. The sorting methods are compared in order to find the most suitable one for Field Programmable Gate Array (FPGA) implementation. Even-odd merge sorting method is selected, and the obtained results are provided in terms of occupied resources and maximum speed.

关键词： LTE turbo coding sorting methods parallel decoding QPP interleaver FPGA

来源：评论

学校读者我要写书评

暂无评论

Efficient Parity Bit Estimation for turbo Codes

Efficient Parity Bit Estimation for Turbo Codes

引用

10th IEEE Workshop on Signal Processing Advances in Wireless Communications

作者： Levanen, Toni Renfors, Markku Tampere Univ Technol Dept Commun Engn FIN-33101 Tampere Finland

ISBN: (纸本)9781424436958

In this paper a novel and efficient method for estimating parity bits in a turbo decoder is presented. The main idea is as follows. First we estimate only information bits in a traditional iterative manner. After the information bits are assumed to be detected correctly or the maximum number of information bit decoding iterations is achieved, we forward all soft information to soft parity estimation blocks. In this way we can improve the parity bit estimation performance and decrease the decoding complexity, compared to the traditional scheme where information and parity bits are jointly estimated in the same iterative loop.

关键词： turbo coding parity bit estimation

来源：评论

学校读者我要写书评

暂无评论

Error Control for Compressed Video Transmission over Next Generation Mobile Networks

Error Control for Compressed Video Transmission over Next Ge...

引用

作者： Ryan Perera University of Surrey

学位级别：博士

Video data claims a significant portion of global mobile data communications, currently standing at 55%. This demand outburst has been due to exceptional display technolo- gies, on-demand video, gaming and live video streaming, to name a few. Despite the massive data rates supported by modern mobile communication technologies, video data is starting to overload mobile networks. This is particularly true in links with low connectivity, where repeat requests flood the system. As solutions for this inevitable demand growth, in addition to efficient video compres- sion methods, more video data error resilience must be sought. One reason video traffic is vulnerable to channel errors is the method it is treated at transmission; treatment as any other generic data type. Video is a unique data type because its ultimate user is not a machine, but a human, and because the contents within the data are inter- dependent on each other. Based on its properties, video compression, transmission methodology, and the decoding function must be adapted. By considering video com- munication as a collaborative effort of these three functions, error resilience can be effectively implemented. Analysis of radio resources available for data transmission in a multipath fading channel reveals that some resources are more robust than others. In the first contribution of this thesis, this characteristic is utilised to impose more resilience to more sensitive data within the video. Reliable means of forecasting the relative robustness of each radio resource are designed. Criteria for identifying the sensitivity of different video data segments are formulated. Finally, a technology is presented to map data to radio resources such that maximum received video quality is achieved. While the focus on the first contribution was on harmonising the transmission methods with the features of the compressed video payload, the second contribution takes an alternative route to error resilience by focusing on t

关键词： Adaptive filter adaptive modulation and coding channel coding channel prediction error resilience EXIT charts fountain codes joint source channel decoding LDPC coding mobile video communication turbo coding unequal error protection variable length codes video compression

来源：评论

学校读者我要写书评

暂无评论

From Source coding to MIMO - A Multi-Level Unequal Error Protection

From Source Coding to MIMO - A Multi-Level Unequal Error Pro...

引用

IEEE Region 10 Conference

作者： Bashar Barmada Saeed Rehman Department of Computer Science Unitec Institute of Technology

ISBN: (纸本)9781509025985

In this paper, unequal error protection (UEP) on different levels of the transmission system is proposed. Starting from the source coding level, two priority layers are produced, high priority (HP) and low priority (LP). At channel coding, each priority layer is turbo encoded with a coding rate that reflects its importance. For modulation, a more immune modulation mode is used to modulate the HP bit stream. Finally at the transmission level, a 3 x 3 MIMO is used, where more transmit antennas and time slots are offered to HP data. This arrangement of inequality over several levels increases the flexibility of the UEP system and leads to a better performance. Results show that the proposed system outperforms other semi-unequal and equal error protection systems over a wide range of channel signal-to-noise ratio (SNR), especially at low SNR values.

关键词： Unequal error protection Multi-layer source coding turbo coding MIMO with spatial-time code

来源：评论

学校读者我要写书评

暂无评论

Analysis and Simulation of the Transmission Distortions of the Mobile Digital Television DVB-SH Part 1: Terrestrial Mode DVB-SH-A with OFDM

Analysis and Simulation of the Transmission Distortions of t...

引用

作者： Polak, L. Brno University of Technology

This paper deals with the latest digital TV standard DVB-SH (Digital Video Broadcasting - Satellite to Handhelds) with focus on utilization of its advantages for the next generation of mobile TV broadcasting. The whole paper consists of two parts. In this first part, after the brief introduction to DVB-SH and related last works review, the simulation model of DVB-SH-A, which is using terrestrial configuration with OFDM transmission mode, is presented. The work is especially focused on the description of new type of forward error correction and system configuration of the DVB-SH-A mode. For the analysis and simulation of the transmission, the original scheme of turbo encoder was modified in this paper. Application for simulation of the transmission in mobile and portable fading transmission channels was developed in MATLAB. Dependences of BER on C/N ratio for all types of payload modulation are compared with focus on mobile TV services availability. Finally, the achieved results are evaluated and clearly discussed.

关键词： Digital television mobile TV DVB-SH-A turbo coding portable reception mobile reception BER

来源：评论

学校读者我要写书评

暂无评论

Equivalent MIMO Channel Matrix Sparsification for Enhancement of Sensor Capabilities

引用

SENSORS 2022年第5期22卷 2041-2041页

作者： Bakulin, Mikhail Kreyndelin, Vitaly Melnik, Sergei Sudovtsev, Vladimir Petrov, Dmitry Moscow Tech Univ Commun & Informat MTUCI Fac Radio & Televis Moscow 111024 Russia Suisse Dept Int Telecommun Acad CH-1202 Geneva Switzerland Peoples Friendship Univ Russia RUDN Univ Dept Informat Technol 6 Miklukho Maklaya Str Moscow 117198 Russia

One of the development directions of new-generation mobile communications is using multiple-input multiple-output (MIMO) channels with a large number of antennas. This requires the development and utilization of new approaches to signal detection in MIMO channels, since the difference in the energy efficiency and the complexity between the optimal maximum likelihood algorithm and simpler linear algorithms become very large. The goal of the presented study is the development of a method for transforming a MIMO channel into a model based on a sparse matrix with a limited number of non-zero elements in a row. It was shown that the MIMO channel can be represented in the form of a Markov process. Hence, it becomes possible to use simple iterative MIMO demodulation algorithms such as message-passing algorithms (MPAs) and turbo.

关键词： MIMO sparse matrix turbo coding

来源：评论

学校读者我要写书评

暂无评论

A low power programmable turbo decoder macro using the SOVA algorithm

引用

IEICE TRANSACTIONS ON ELECTRONICS 2004年第4期E87C卷 510-519页

作者： Gambe, H Ohbuchi, K Ishihara, T Zakoji, T Araki, K Fujitsu Labs Ltd Kawasaki Kanagawa 2118588 Japan Tokyo Inst Technol Tokyo 1528552 Japan

turbo codes are of particular use in applications of wireless communication systems, where various types of communication are required and the data rate must be changed, depending on the situation. In such applications, adaptation of turbo coding specifications is required in terms of coding block size, data speed, parity bit arrangement or configuration of a convolutional coder, as well as the need for real time processing. We present new ideas to provide these capabilities for a low power decoder circuit by focusing on the configuration of a convolutional decoding algorithm, which occupies a significant proportion of the hardware circuit. We utilize the Soft Output Viterbi Algorithm (SOVA) for the base algorithm, produced by adding the concept of a soft output to the Viterbi Algorithm (VA). The Maximum A Posteriori (MAP) algorithm and its simplified version of MAX-LOG-MAP are also widely known. MAP is recognized as a means of achieving very good bit error rate (BER) characteristics. On the other hand SOVA has been regarded as a method which can be simply implemented with less computational resources, but at a cost of higher degradation. However, in many of recent systems we combine turbo coding with some other method such as Automatic Repeat Request (ARQ) to maintain a good error correction performance and we only have to pay attention to the performance in the range of low carrier-to-noise ratio (CNR), where SOVA has fairly satisfactory BER characteristics. This makes the SOVA approach attractive for a low power programmable IP macro solution, when the fundamental advantage of SOVA is fully utilized in the implementation of an LSI circuit. We discuss the processing algorithm and circuit configuration and show that about 40% reduction in power consumption can be achieved. It is also shown that the IP macro can handle 1.5 Mbps information decoding at 100 MHz clock rate.

关键词： turbo coding SOVA Viterbi algorithm trace back MAX-LOG-MAP sliding window

来源：评论

学校读者我要写书评

暂无评论

Systematic-bit-selection distributed with selective-relaying

引用

Journal of Beijing Institute of Technology 2014年第1期23卷 73-77页

作者： HOU Shu-juan LI Ling-yun QIN Xue-fang School of Information and Electronics Beijing Institute of Technology Beijing 100081 China

An improved distributed turbo coding （DTC） scheme, namely, systematic-bit-selection DTC, is proposed for a two-hop relay network implementing selective-relaying （SR）. In the scheme, source broadcasts a punctured turbo code in order to increase the successful decoding rate of relay. The relay forwards systematic-bit to the destination in case of successful cyclic redundancy check （CRC）. From the two versions of systematic-bit coming from relay and source respectively, the des- tination selects the one with higher signal-to-noise ratio （SNR） for turbo decoding. Simulation re- suits show the improved bit error rate （BER） performance of our scheme.

关键词： distributed coding relay network turbo coding selective-relaying

来源：评论

学校读者我要写书评

暂无评论

A COMBINED ENCRYPTION AND ERROR CORRECTION SCHEME: AES-turbo

引用

ISTANBUL UNIVERSITY-JOURNAL OF ELECTRICAL AND ELECTRONICS ENGINEERING 2009年第1期9卷 891-896页

作者： Cam, Hakan Ozduran, Volkan Ucan, Osman N. Turkish Air Force Acad ASTIN Aeronaut & Space Technol Inst Comp Engn Istanbul Turkey Istanbul Univ Engn Fac Elect & Elect Eng Dept TR-34320 Istanbul Turkey

In this paper, we introduced a new type of Encryption and Error Correction scheme, which is called "A Combined Encryption and turbo coding Scheme: AES-turbo". Although in previous studies error correction and encryption are handled independently, we combined error correction and Encryption functionality into one single step. This combined System's performances are evaluated in AWGN (Additive White Gaussian Noise) channel type. The results are compared with the system employing ideal encryption and decryption.

关键词： Advanced Encryption Standard(AES) turbo coding Encryption and Error Correction

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：