检索结果-内蒙古大学图书馆

Secure echo-hiding audio watermarking method based on improved PN sequence and robust principal component analysis

IET SIGNAL PROCESSING 2020年第4期14卷 229-242页

作者： Wang, Shengbei Wang, Chao Yuan, Weitao Wang, Lin Wang, Jianming Tianjin Polytech Univ Tianjin Key Lab Autonomous Intelligence Technol S Tianjin 300387 Peoples R China Techfantasy Co Ltd Tianjin 300387 Peoples R China

Echo-hiding has been widely studied for audio watermarking. This study proposes a more secure echo-hiding method based on modified pseudo-noise (PN) sequence and robust principal component analysis (RPCA). In the proposed method, the RPCA is used to decompose the original audio signal into low-rank and sparse parts and then a pair of opposite modified PN sequences is employed to embed watermarks. The modified PN sequence improves the robustness of watermark detection by providing additional correlation peaks. Meanwhile, benefit from the RPCA and the opposite PN sequences, the security of the proposed method is improved since watermarks cannot be detected from the whole signal even if the PN sequence is known, which is an obvious improvement compared with the previous PN-based echo-hiding methods. In the watermark detection process, the authors make use of the low-rank and sparse characteristics of the watermarked signal to detect watermarks from the low-rank and sparse parts, respectively. Based on this basic framework, they also propose a multi-bit embedding scheme, which obtains a doubled embedding capacity compared with the previous PN-based echo-hiding methods. The proposed method was evaluated with respect to inaudibility, security, and robustness. The experiment results verified the effectiveness of the proposed method.

关键词： principal component analysis image coding audio watermarking audio coding watermark detection process watermarked signal secure echo-hiding audio watermarking method improved PN sequence robust principal component analysis pseudonoise sequence RPCA audio signal opposite modified PN sequences PN-based echo-hiding methods echo-hiding method

来源：评论

学校读者我要写书评

暂无评论

Research on the Equivalence of Pulsed Interference Signal and CW Signal in DSSS Communication System

Research on the Equivalence of Pulsed Interference Signal an...

引用

International Conference on Mechatronics and Information Technology (ICMIT 2013)

作者： Wang, Ying Dong, Jiang ShenZhen Inst Informat Technol Rm 1603 Keji Bldg Shenzhen Peoples R China

ISBN: (纸本)9783037859414

Pulsed interference signal and pure frequency continuous wave (CW) jamming signal have the same effect on performance of bit error rate (BER). Due to equivalence, we can effectively simplify the complex of the direct sequence spread spectrum (DSSS) communication system. The equivalence will be simulated by the software SystemView in systematic level.

关键词： Direct sequence Spread Spectrum (DSSS) pseudonoise sequence Simulation

来源：评论

学校读者我要写书评

暂无评论

Least-Squares-Based Iterative Multipath Super-Resolution Technique

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2013年第3期61卷 519-529页

作者： Nam, Wooseok Kong, Seung-Hyun Samsung Informat Syst Amer Mobile Solut Lab San Diego CA 92121 USA Korea Adv Inst Sci & Technol Grad Sch Green Transportat Taejon 305701 South Korea

In this paper, we investigate the multipath resolution problem for direct sequence spread spectrum signals. To resolve multipath components arriving within a very short interval, we propose a new multipath super-resolution algorithm based on the iterative least-squares method. The proposed least-squares-based iterative multipath super-resolution (LIMS) algorithm exploits a triangular shaped auto-correlation function (ACF) of the pseudonoise (PN) sequence and simplifies the least-squares parameter estimation procedure using iterative and algebraic operations. This results in an algorithm demanding low computational load with a high multipath resolution capability. It is also discussed that the LIMS algorithm can be applied for recursive multipath tracking of source localization systems, such as the global navigation satellite systems (GNSS). Simulation results show that the LIMS algorithm maintains its good performance even in a low C/N-0 or severe multipath interference conditions.

关键词： Global navigation satellite systems (GNSS) least-squares multipath channel pseudonoise sequence super-resolution

来源：评论

学校读者我要写书评

暂无评论

Efficient time and frequency synchronization for OFDM based wireless indoor communication over rician fading channel

Efficient time and frequency synchronization for OFDM based ...

引用

10th IEEE International Symposium on Consumer Electronics (ISCE 2006)

作者： Kim, Hee Wook Kang, Kunseok Ahn, Do-Seob ETRI Korea Broadband Wireless Transmiss Team Taejon South Korea ETRI Global Area Wireless Technol Res Grp Taejon South Korea

ISBN: (纸本)1424402158

We present joint frame synchronization and frequency offset estimation using a new preamble with pseudo-noise sequences in time domain for orthogonal frequency division multiplexing (OFDM) based wireless communication over rician fading channel. By the proposed scheme, the accuracy of the timing offset estimator is definitely improved and an estimation range of the frequency offset normalized by the carrier spacing is extremely extended to one half of the total signal bandwidth with only one pilot symbol which has lower PAPR than those in conventional schemes. The performance of the proposed method is shown by simulation.

关键词： OFDM synchronization preamble pseudonoise sequence

来源：评论

学校读者我要写书评

暂无评论

Distributional properties of d-FCSR sequences

引用

JOURNAL OF COMPLEXITY 2004年第2-3期20卷 305-317页

作者： Klapper, A Univ Kentucky Dept Comp Sci Lexington KY 40506 USA Inst Adv Study Sch Math Princeton NJ 08540 USA

In this paper we study the distribution properties of d-FCSR sequences. These sequences have efficient generators and have several good statistical properties. We show that for d = 2 the number of occurrences of an fixed size subsequence differs from the average number of occurrences by at most a small constant times the square root of the average. (C) 2003 Elsevier Inc. All rights reserved.

关键词： FCSR sequence pseudonoise sequence pseudorandom sequence distribution property

来源：评论

学校读者我要写书评

暂无评论

Cyclically permutable codes for rapid acquisition in DS-CDMA systems with asynchronous base stations

引用

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2001年第1期19卷 83-94页

作者： Sriram, S Hosur, S Texas Instruments Inc DSPS R&D Ctr Dallas TX 75243 USA

There has been significant recent interest in cellular systems employing direct sequence (DS) code division multiple access (CDMA), with no synchronization requirement between base stations (BS), especially in the context of the so-called third-generation (3G) wireless systems. In this case, since neighboring BSs use different spreading sequences, the mobile must first determine the spreading sequence being used by the BS(s) from which the mobile receives sufficiently strong signals. To facilitate acquisition, the total set of spreading sequences is divided into groups, and the group identification is transmitted over a synchronization channel. This paper describes a novel mechanism for transmitting the group identification (ID) using cyclically permutable (CP) codes;this scheme results in significant reduction in the search space, allowing for rapid acquisition. The technique described is currently a component of the radio access technology in the 3G partnership project (3GPP) proposal to the International Telecommunications Union (ITU) for 3G wireless systems (IMT-2000), An analysis of the three-stage search process required for acquisition and cell search is also presented, and simulation results are shown to demonstrate the efficacy of this approach.

关键词： 3G acquisition cell search correlation cyclically permutable codes pseudonoise sequence spread spectrum synchronization W-CDMA

来源：评论

学校读者我要写书评

暂无评论

Adaptive acquisition of PN sequences for DSSS communications

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 1998年第8期46卷 993-996页

作者： Kim, CJ Lee, HJ Lee, HS ETRI Taejon 305600 South Korea Korea Adv Inst Sci & Technol Dept Elect Engn Taejon 305701 South Korea

Since the received signal levels in mobile communications are unknown and location varying, acquisition schemes for pseudonoise (PN) sequences with fixed thresholds cannot provide satisfactory performance, This fixed-threshold scheme may cause too many false alarms or result in low detection probability for a selected threshold value. In this letter we present an adaptive acquisition scheme for PN sequences which estimate the background power level, multiply it with threshold coefficient to keep the false alarms constant, and use it as a threshold.

关键词： adaptive acquisition pseudonoise sequence spread-spectrum communication

来源：评论

学校读者我要写书评

暂无评论

pseudonoise sequenceS BY CHAOTIC NONLINEAR MAPS AND THEIR CORRELATION-PROPERTIES

引用

IEICE TRANSACTIONS ON COMMUNICATIONS 1993年第8期E76B卷 855-862页

作者： KOHDA, T TSUNEDA, A Kyushu Univ Fukuoka Japan

A simple method is given for obtaining new families of pseudonoise (PN) sequences based on chaotic nonlinear maps. Such families are worse than the Gold and the Kasami families in terms of maximum cor-relation values. Nevertheless, such a method has several advantages: the generation is easy, and various families with an arbitrary family size and sequence period can be *** because nonlinear maps have several parameters to be secret keys for communications security. Hence these sequences are good candidates of spreading sequences for CDMA.

关键词： pseudonoise sequence EVEN-(ODD-) CROSS-CORRELATION FUNCTION CHAOS NONLINEAR ERGODIC MAP CHEBYSHEV BIT sequence

来源：评论

学校读者我要写书评

暂无评论

Even‐length real‐valued cyclically orthogonal pseudonoise sequences with small absolute value

引用

Electronics and Communications in Japan (Part III: Fundamental Electronic Science) 1993年第2期76卷 1-9页

作者： Tanada, Yoshihiro Yoshida, Hiroshi Nagasawa, Yoji Faculty of Engineering Kagoshima University Kagoshima 890 Japan

This paper discusses the even‐length real‐valued cyclically orthogonal pseudonoise (PN) sequences with small absolute values as the PN sequence for spread spectrum communication. First, the sequence of maximum absolute value 2 with cubic or inverse phase parameters is considered. By replacing the sequence variable by the power of the primitive root and by regarding the power as the sequence variable, an orthogonal PN sequence is obtained. There exists the same number of such sequences as the number of primitive roots, and the cross‐correlation function is relatively small if the period is large. By convolving a sequence with itself, a set of sequences is obtained which has relatively small absolute value of the sequence and relatively small absolute value of cross correlation. It is proposed also to convolve a sequence with other sets of sequences. The sequence considered in this paper is suited to the digital correlation processing using the fast‐Fourier transform when the period is 4, 16, 256, 65, 536, …. Copyright © 1993 Wiley Periodicals, Inc., A Wiley Company

关键词： decimation of sequence even number period fast‐Fourier transform pseudonoise sequence real‐valued orthogonal sequence

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：