检索结果-内蒙古大学图书馆

block coding scheme based on complementary sequences for multicarrier signals

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1997年第11期E80A卷 2136-2143页

作者： Ochiai, H Imai, H Institute of Industrial Science University of Tokyo Tokyo 106 Japan

A novel block coding scheme based on complementary sequences which is capable of both error correction and peak to average power ratio reduction has been proposed for M-ary PSK multicarrier systems. Generator matrices for the number of carriers N = 2(k) where k = 2,3,... are derived. The effectiveness of the scheme has been confirmed by computer simulations.

关键词： multicarrier modulation multiphase complementary sequence peak to average power ratio block coding

来源：评论

学校读者我要写书评

暂无评论

block coding SCHEME FOR REDUCING PAPR IN OFDM SYSTEMS WITH LARGE NUMBER OF SUBCARRIERS

引用

Journal of Electronics(China) 2004年第6期21卷 482-489页

作者： JiangTao ZhuGuangxi ZhengJianbin DeptofElectron.＆Info.Eng. HuazhongUniversityofScienceandTechnologyWuhan430074

The major drawback in Orthogonal Frequency Division Multiplexing (OFDM) system is due to the high Peak-to-Average Power Ratio (PAPR), so the performance of the system is significantly degraded by the nonlinearity of a High Power Amplifier (HPA) in the *** order to mitigate distortion, a block coding scheme for reducing PAPR in OFDM systems with large number of subcarriers based on complementary sequences and predistortion is proposed,which is capable of both error correction and PAPR reduction. Computer simulation results show that the proposed scheme significantly improves Bit Error Rate(BER) performance as compared to an uncoded system when an HPA is employed or a coded system without predistortion.

关键词： block coding Complementary sequence Peak-to-Average Power Ratio (PAPR) Predistortion Orthogonal Frequency Division Multiplexing(OFDM)

来源：评论

学校读者我要写书评

暂无评论

Bstj 45: 6. July-August 1966: a Bound on the Reliability of block coding with Feedback. (Savage, J.E.)

引用

2016年

Bstj 45: 6. July-August 1966: a Bound on the Reliability of block coding with Feedback. (Savage, J.E.) by published by

关键词： (savage, additive gaussian bell system block block coding bound channel code coding decoding decoding error error exponent feedback feedback strategy feedback. gaussian noise j.e.) list list decoding middle range probability random code system technical

来源：评论

学校读者我要写书评

暂无评论

Word order detection in English classroom teaching based on improved genetic algorithm of block coding

引用

JOURNAL OF INTELLIGENT & FUZZY SYSTEMS 2021年第4期40卷 6901-6912页

作者： Deng Bowen Guangdong Ocean Univ Sch Foreign Languages Cunjin Coll Zhanjiang Guangdong Peoples R China Sejong Univ Dept Econ Seoul South Korea

The performance of the speech recognition system for English classroom teaching is largely affected by the surrounding environment. These interference signals will seriously reduce the quality and intelligibility of the speech signal, thereby greatly reducing the performance of the far-field speech recognition system. Aiming at word order detection in English classroom teaching, this paper proposes an analysis model based on block coding and improved genetic algorithm. Moreover, for DNN-based single-channel speech enhancement algorithms, this paper proposes PDNNs and PLSTMs to solve the problem of serious performance degradation of prototype DNN speech enhancement under low signal-to-noise ratio. This method decomposes the entire enhancement task into multiple subtasks to complete, and the previously completed subtasks will provide prior knowledge for the subsequent subtasks, so that the subsequent subtasks can learn its goals better. In general, the experimental results prove the reliability of the model constructed in this paper.

关键词： block coding genetic algorithm machine learning word order detection

来源：评论

学校读者我要写书评

暂无评论

Dynamic block coding for Image Filtration in Medical Applications

Dynamic Block Coding for Image Filtration in Medical Applica...

引用

International Conference on Communication and Signal Processing

作者： Somashekhar Swamy P. K. Kulkarni Computer Science department V.T.U Belagav Karnataka India Electronics and Electrical Engineering Department PDACE Karnataka India

ISBN: (纸本)9781467385497

Image noise effects were observed in various real time applications. In different critical analysis such as astronomical data analysis, metrological data analysis, medical data analysis, information's at finer level representation are more important. Finer information's, are basically condensed in a compressed image. To visualize these finer information's, image zooming are done, where images in zoom level reflects a blurriness in the visualization. This paper develops a new approach to image filtration process using dynamic block coding for image denoising and information preservation. The suggested approach is evaluated over medical images to validate its performances.

关键词： Image filtration Median filter block coding Medical images

来源：评论

学校读者我要写书评

暂无评论

High-capacity data hiding in encrypted images based on compressive sensing and intra-block difference coding

引用

APPLIED INTELLIGENCE 2023年第21期53卷 26240-26254页

作者： Qin, Baokun Zheng, Hongying Xiao, Di Chongqing Univ Coll Comp Sci Chongqing 400044 Peoples R China

Data hiding in encrypted images (DHEI) can not only protect the content of the original image but also manage and control the encrypted image, which is important for protecting personal privacy and improving the efficiency of third-party data processing. However, the current DHEI algorithms still have room for progress in the embedding capacity. In this paper, a high-capacity DHEI algorithm based on compressive sensing and intra-block difference coding is proposed. The content-owner firstly utilizes the compressive sensing progressive reconstruction prediction method to obtain prediction error, then encodes the quantized prediction error and measurements, and finally gets the encrypted image by the stream cipher algorithm. The data-hider embeds secret data by bit substitution. The receiver executes the extraction of secret data or the recovery of the original image according to the possessed key. Experimental results show that our method achieves higher embedding capacity compared with other methods, and the reconstruction quality of the original image remains reliable at high embedding rate.

关键词： High-capacity Compressive sensing Data hiding Encrypted images block coding

来源：评论

学校读者我要写书评

暂无评论

LDPC block-coding schedule based on Queen-matrix

LDPC block-coding schedule based on Queen-matrix

引用

4th International Conference on Wireless Communications, Networking and Mobile Computing

作者： Luo Xiling Zhang Jiayi Zhang Jun BUAA Sch Elect & Informat Engn Beijing Peoples R China

ISBN: (纸本)9781424421077

The general coding schedule of low density parity codes (LDPC) have the problems of slow coding speed and difficult implementation in hardware. Based on the irregular Queen-matrix LDPC construction algorithm derived from n-queens problem, this paper designed an optimized block-coding schedule according to construction codes' dimension and memory's bandwidth. The block-coding schedule can reduce the intermedial size of data storages and be propitious to hardware implementation by using data source and generating matrix' s division. The experimental results show that comparing with the general coding schedule, the block-coding schedule can make coding speed be improved by 14.6%similar to 36.1% at the cost of a little increasing of bit error ratio (BER) because it arranges the submatrix multiplication in parallel prior to sum of them.

关键词： Queen-matrix block coding LDPC

来源：评论

学校读者我要写书评

暂无评论

Reversible Data Hiding in Encrypted Images With Asymmetric coding and Bit-Plane block Compression

引用

IEEE TRANSACTIONS ON MULTIMEDIA 2024年 26卷 10174-10188页

作者： Zhang, Xianquan He, Feiyi Yu, Chunqiang Zhang, Xinpeng Yang, Ching-Nung Tang, Zhenjun Guangxi Normal Univ Key Lab Educ Blockchain & Intelligent Technol Minist Educ Guilin 541004 Peoples R China Guangxi Normal Univ Guangxi Key Lab Multisource Informat Min & Secur Guilin 541004 Peoples R China Fudan Univ Sch Comp Sci Shanghai 200433 Peoples R China Natl Dong Hwa Univ Dept Comp Sci & Informat Engn Hualien 974 Taiwan

Reversible data hiding in encrypted images (RDHEI) is an effective technology of protecting private data. In this paper, a high-capacity RDHEI method with asymmetric coding and bit-plane block compression is proposed. Our major contributions are twofold. (1) We propose an asymmetric coding technique for processing prediction error (PE) blocks before encryption. The proposed asymmetric coding technique does not generate the sign bit-plane and facilitates massive zeros converging on the high bit-planes. This is beneficial to reserve the embedding room. (2) We present a bit-plane block compression technique for improving the embedding capacity. This technique divides the PE codes in a block into two parts which are both compressed and thus contribute a large embedding room. Experimental results demonstrate that the average embedding rates of the proposed method are 4.174, 4.08 and 3.467 bpp on the BOSSBase, BOWS-2 and UCID datasets, respectively. Comparisons show that our average embedding rates on the three datasets are all bigger than those of some state-of-the-art methods.

关键词： Image coding Cryptography Encryption Streaming media Data mining Cloud computing Receivers Asymmetric coding bit-plane block compression block coding prediction error reversible data hiding

来源：评论

学校读者我要写书评

暂无评论

Single-Carrier Single-block Differential Space-Frequency coding Transmission Over the Frequency-Selective Fading Channels

引用

WIRELESS PERSONAL COMMUNICATIONS 2009年第1期49卷 133-147页

作者： Zhu, Jiangzhang Jin, Tao Du, Qingsong Cent S Univ Forestry & Technol Coll Elect & Informat Engn Changsha Hunan Peoples R China Tsinghua Univ Res Inst Shenzhen 518057 Peoples R China Hunan Univ Coll Comp & Commun Changsha 410082 Hunan Peoples R China Natl Univ Def Technol Coll Elect Sci & Engn Changsha Hunan Peoples R China

In this paper, a single-carrier single-block differential space-frequency block coding scheme for multiple input multiple output frequency-selective fading channels is proposed. In the proposed scheme, an alternative constant modulus single-carrier transmission is adopted, which significantly mitigates the sensitivity to the nonlinear distortion while having comparable lower complexity to the orthogonal frequency division multiplexing modulus. Based on this, subgrouping the signal transmit matrix through the block matrix method and fatherly differential space-frequency complex orthogonal coding on each subblocks, it not only transmits the differentially encoded signal matrix within one symbol block periods regardless of the number of transmit antennas, but also achieves the available spatial and frequency diversities without the requirement of multichannel estimation at the receiver. In the proposed scheme, it is only required that the fading channels keep approximately constant within each subblock during one symbol block transmission period, and thus can be more robust and effective to combat the channel rapidly fading with even lower bit error ratio. Theoretical analysis and corroborating simulation under various channel conditions shows that, our proposed scheme yields superior performance to previously proposed differential schemes.

关键词： Single-carrier single-block Differential space-frequency block coding Unitary space-time modulation block matrix Frequency-selective fading Bit error ratio

来源：评论

学校读者我要写书评

暂无评论

An Image Secret Sharing Technique with block Based Image coding 5

An Image Secret Sharing Technique with Block Based Image Cod...

引用

5th International Conference on Communication Systems and Network Technologies (CSNT)

作者： Das, Sujit Kumar Dhara, Bibhas Chandra Jadavpur Univ Dept Informat Technol Kolkata India

ISBN: (纸本)9781479917976

A (t, n) threshold secret image sharing scheme generates n share images from a secret image in such a way that any t or more share images can be used to reconstruct the secret image. In this paper we have proposed a (t, n) secret image sharing scheme where the secret image is first encoded by block based lossy compression technique and define t sub-images. The image compression technique gives a good quality image. To enhance the security level, the sub-images are scrambled by Arnold transform and then shares are generated. Finally, image hiding (i.e., steganography) concept is adopted to hide the shares within cover images. The proposed method gives good quality of the stego images.

关键词： Secret Sharing Secret Image Sharing block coding Arnold Transform Steganography

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：