检索结果-内蒙古大学图书馆

2-D Single-Port phase coding Meta-Antenna Leveraging Frequency Diversity for Microwave Imaging

IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS 2024年第11期23卷 3421-3425页

作者： Wei, Yifei Chen, Xinhao Liu, Baiyang Huang, Yi Duan, Chaijie Zhang, Qingfeng Southern Univ Sci & Technol Dept Elect & Elect Engn State Key Lab Opt Fiber & Cable Manufacture Techno Shenzhen 518055 Peoples R China Natl Ctr Appl Math Shenzhen NCAMS Shenzhen 518055 Peoples R China Shenzhen Technol Univ Coll Big Data & Internet Shenzhen 518118 Peoples R China Shenzhen HUAYI Med Technol Co Ltd Shenzhen Peoples R China

The diversity of the field pattern in a radiation aper-ture plays a pivotal role on the capacity enhancement of microwave imaging and sensing. Conventional methodologies typically em-ploy multiple ports to excite a 2-D aperture for frequency diver-sity enhancement. However, multiport excitation poses significant challenges for transceivers when multiple-input-multiple-output(MIMO) technology is implemented, while employing switches can result in slower imaging speed. This letter presents a single-port2-D phase coding planar meta-antenna that generates frequency diverse radiation fields, aiming to achieve single-shot high-speed microwave imaging. A prototype of meta-antenna with 13.34 lambda(0 )x 6.67 lambda(0 )aperture size is designed and fabricated for microwaveimaging within 10 GHz to 15 GHz. It achieves a spatial resolution of5mminthey-direction and 9 mm in thex-direction for experimental demonstration, which finally validates the proposed diversity-enhanced meta-antenna. The proposed meta-antenna may findwide applications in integrated communication and sensing

关键词： Imaging Frequency diversity Microwave imaging Microwave integrated circuits Microwave communication Microwave FET integrated circuits Apertures meta-antenna microwave imaging phase coding

来源：评论

学校读者我要写书评

暂无评论

Coherent Detected Secure Point-to-Point Optical Fiber Transmission using Ultra-Dense Optical Spectral phase coding (UD-SPC) and Multilevel BCJR Equalization

Coherent Detected Secure Point-to-Point Optical Fiber Transm...

引用

Asia Communications and Photonics Conference (ACP)

作者： Hong, Xuezhi Lu, Yang He, Sailing SCNU ZJU SCNU Joint Res Ctr Photon Guangzhou 510006 Guangdong Peoples R China Zhejiang Univ Joint Res Ctr Photon Hangzhou 310058 Peoples R China Lund Univ Royal Inst Technol Lund Sweden

A secure P2P optical fiber communication scheme based on ultra-dense optical spectral phase coding (UD-SPC) is proposed. The multi-code interference is suppressed by increasing the memory of the multilevel BCJR equali... 详细信息

ISBN: (纸本)9781467362740

关键词： Optical fiber transmission phase coding Secure multilayers Equalization optical

来源：评论

学校读者我要写书评

暂无评论

Multiple Access Applications of Transform Domain Communication System Based on phase coding 5

Multiple Access Applications of Transform Domain Communicati...

引用

IEEE 5th International Conference on Big Data and Cloud Computing (BDCloud)

作者： Sun, Haixin Cao, Fucheng Qin, Hongwu Changchun Univ Sch Elect & Informat Engn Changchun Peoples R China

ISBN: (纸本)9781467371834

Transform Domain Communication System (TDCS) has been proposed as a new candidate applied in the cognitive radio (CR) environment since it can avoid existing users or jammers intelligently over a given bandwidth. The TDCS achieves noise-like property and orthogonality characteristic by generating a PR phase vector through a random phase coding processing. In this paper, a new implementation of TDCS is proposed for multiple access application by using spreading sequence with phase coding for the PR phase vector generation. The analysis and simulation of the selection of spreading sequence are studied and the related parameters are discussed. The simulation results demonstrate that the proposed scheme provides good bit error rate in multiple access environments.

关键词： Transform domain communication system phase coding multiple access spreading sequence

来源：评论

学校读者我要写书评

暂无评论

Robust and reliable audio watermarking based on phase coding 40

Robust and reliable audio watermarking based on phase coding

引用

40th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2015

作者： Ngo, Nhut Minh Unoki, Masashi School of Information Science Japan Advanced Institute of Science and Technology 1-1 Asahidai Nomi Ishikawa Japan

ISBN: (纸本)9781467369978

This paper proposes a novel robust audio watermarking method based on phase coding. The quantization index modulation technique is employed for embedding watermarks into the phase spectrum of audio signals. To increase robustness of the proposed method, the region of phase spectrum that is resistant against attacks is selected for embedding. We experimentally analyzed the phase spectrum to find out which region is not distorted under attacks. On the other hand, the quantization step size is suitably selected so that the modification of phase does not cause severe distortion in sound quality. The experimental results show that the watermarks could be kept inaudible in audio signals and robust against attacks. The proposed method has the ability to embed watermarks into audio signals up to 400 bits per second with a bit error rate of less than 1%. © 2015 IEEE.

关键词： audio watermarking phase coding quantization index modulation robustness

来源：评论

学校读者我要写书评

暂无评论

Mobile Phone Imaging Module with Extended Depth of Focus Based on Axial Irradiance Equalization phase coding

Mobile Phone Imaging Module with Extended Depth of Focus Bas...

引用

Conference on Digital Photography VII

作者： Sung, Hsin-Yueh Chen, Po-Chang Chang, Chuan-Chung Chang, Chir-Weei Yang, Sidney S. Chang, Horng Natl Tsing Hua Univ Dept Elect Engn Inst Photon Technol Hsinchu 300 Taiwan Ind Technol Res Inst Elect & Opto Elect Res Lab Hsinchu 300 Taiwan

ISBN: (纸本)9780819484130

This paper presents a mobile phone imaging module with extended depth of focus (EDoF) by using axial irradiance equalization (AIE) phase coding. From radiation energy transfer along optical axis with constant irradiance, the focal depth enhancement solution is acquired. We introduce the axial irradiance equalization phase coding to design a two-element 2-megapixel mobile phone lens for trade off focus-like aberrations such as field curvature, astigmatism and longitudinal chromatic defocus. The design results produce modulation transfer functions (MTF) and phase transfer functions (PTF) with substantially similar characteristics at different field and defocus positions within Nyquist pass band. Besides, the measurement results are shown. Simultaneously, the design results and measurement results are compared. Next, for the EDoF mobile phone camera imaging system, we present a digital decoding design method and calculate a minimum mean square error (MMSE) filter. Then, the filter is applied to correct the substantially similar blur image. Last, the blur and de-blur images are demonstrated.

关键词： mobile phone lens extended depth of focus phase coding axial irradiance equalization computational imaging digital decoding image restoration minimum mean square error filter

来源：评论

学校读者我要写书评

暂无评论

Simulation Research on How to Improve the Range Resolution of Pulse Compression Radar Based on phase coding

Simulation Research on How to Improve the Range Resolution o...

引用

International Conference on Electrical Information and Mechatronics (ICEIM)

作者： Tang, Yu Zhongkai Univ Agr & Engn Coll Informat Guangzhou 510225 Guangdong Peoples R China

ISBN: (纸本)9783037853115

phase coded radar signal is one of the pulse-pulse modulation signal in the radar system. Based on the characteristics of matched filtering, we theoretically analyze the basic principle of the phase coded compression radar system. In the Matlab platform, we set up a simulation model which is used for matching filter, when the radar transmitting signal is Barke code signal. The simulation results show that Echo signal can obtain certain pulse compression ratio. By the matched filter, the main lobe amplitude of 13 bits Barker code signal is 22 times the rate of side-lobe. 13 bits Barker codes by the matched filter have the maximum pulse compression ratio.

关键词： phase coding pulse compression radar range resolution Barker code

来源：评论

学校读者我要写书评

暂无评论

A novel steganalysis algorithm of phase coding in audio signal

A novel steganalysis algorithm of phase coding in audio sign...

引用

6th International Conference on Advanced Language Processing and Web Information Technology

作者： Zeng, Wei Ai, Haojun Hu, Ruimin Natl Engn Res Ctr Multimedia Software Wuhan 430072 Peoples R China

ISBN: (纸本)9780769529301

Audio steganalysis has attracted more attentions recently. phase steganalysis is one of the most challenging research fields. In this paper, a novel algorithm to detect phase coding steganography in audio signal is proposed. It is based on analysis of the phase discontinuities, and can be described as follows. Firstly, it takes FFT transform of special segment of audio and unwraps the phases of each audio sample, then extracts the phase difference between neighboring samples. Secondly, in order to monitor the change of phase difference, it calculates the five statistical features of phase difference for steganalysis. Thirdly, the SVM classifier is utilized for classification. All of the 800 various audios are trained and tested in our experimental work. With various embedding parameters for training and testing audios, the proposed algorithm can achieve a good classification, and the correct rate of detecting is up to 95%.

关键词： phase difference audio signals Audio phase coding phase

来源：评论

学校读者我要写书评

暂无评论

A Solution to Harmonic Frequency Problem: Frequency and phase coding-Based Brain-computer Interface

A Solution to Harmonic Frequency Problem: Frequency and Phas...

引用

International Joint Conference on Neural Networks (IJCNN)

作者： Wong, Chi Man Wang, Boyu Wan, Feng Mak, Peng Un Mak, Pui In Vai, Mang I. Univ Macau Dept Elect & Elect Engn Fac Sci & Technol Taipa Peoples R China

ISBN: (纸本)9781424496365

In this paper, we propose a modified visual stimulus generation method and feature detection algorithm to design a frequency and phase coding steady-state visual evoked potential (SSVEP) based brain-computer interface (BCI). By utilizing both frequency and phase information, we solve the harmonic frequency problem in our proposed SSVEP-BCI system. The offline experimental results show that the proposed feature detection algorithm can enhance the classification rate over 10% (from 69%+/- 12% to 82%+/- 8%) even though only one signal electrode is used and the harmonic frequencies (6367Hz, 13.33Hz, 8357Hz and 17.14Hz) are employed.

关键词： Joints Neural networks USA Councils brain-computer interfaces coding-based brain-computer interface encoding feature detection algorithm frequency 13.33 Hz frequency 17.14 Hz frequency 6.67 Hz frequency 8.57 Hz frequency coding harmonic frequency problem medical signal processing phase coding signal classification signal classification rate signal electrode steady-state visual evoked potential visual evoked potentials visual stimulus generation method

来源：评论

学校读者我要写书评

暂无评论

The Adaptive Multi-Level phase coding Method in Audio Steganography

引用

IEEE ACCESS 2019年 7卷 129291-129306页

作者： Alsabhany, Ahmed Abduljabbar Ridzuan, Farida Azni, A. H. USIM FST Nilai 71800 Malaysia USIM ISI CyberSecur & Syst Res Unit Nilai 71800 Malaysia

Audio steganography allows and inspires many researchers to design methods for secure communication. Based on the evaluation on the existing methods, it was found that most methods focused on one or two requirements while disregarding others, causing imbalanced performance. Moreover, most methods lack adaptivity and dynamic allocation. Therefore, in this research, a method called Adaptive Multi-level phase coding (AMPC) was proposed to optimize the above issues. The reverse logic of the main tradeoffs was used to empirically design several embedding levels that that simultaneously attained good performance for all aspects as much as possible. Then, an adaptive component was added by selecting the embedding level that provided the best performance for each embedding process. Moreover, the error spreading factor was introduced to achieve a fair payload distribution. The performance balance objective requires a new formulation that will enable the accurate selection of the degree of modification, multiple-bit embedding per modification, and reduced retrieval errors. As a result, the interval centering quantization (ICQ) was formulated and implemented in the proposed method. The experimental results show that AMPC successfully fulfilled the research objectives. Also, AMPC surpassed other phase coding methods in all aspects while time-domain methods achieved the highest transparency and capacity with the lowest robustness. Moreover, experiments show that the implementation of adaptive multi-level concept is able to improve the existing method's performance significantly. In summary, AMPC was able to achieve a stable embedding rate of 33 Kbps at 35 dB of SNR, which is higher than the recorded embedding rate of other phase coding methods.

关键词： Audio steganography phase coding adaptive multi-level AMPC LSB

来源：评论

学校读者我要写书评

暂无评论

Ranging and Doppler Localization Using Golay Codes as the phase coding Signal

引用

MEHRAN UNIVERSITY RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY 2012年第1期31卷 1-12页

作者： Hussain, Aamir Malik, Muhammad Bilal Natl Univ Sci & Technol Coll Elect & Mech Engn Rawalpindi Pakistan

In this paper we develop a signal processing algorithm for the detection, ranging and Doppler localization of moving target using Golay code as the phase coding signal. We exploit the side-lobes suppression property of Golay code, that occurs in complementary code pair, for side-lobe free target detection, range estimation and Doppler localization. Golay code based phase coding is achieved using QPSK (Quadrature phase Shift Keying) scheme. When the transmitted signal is reflected from a moving target, its complex demodulation is carried out at the receiver. This is followed by correlation of each component of demodulated signal with one member of the complementary Golay code pair separately. The correlation results of the two channels are added together, leading to effective side-lobes suppression when phase and frequency of the demodulating carriers match with that of the received signal. The shift in the time index of the correlation peak gives the range to the target. Frequency of the demodulating carriers at which side-lobe free correlation peak occurs at the output indicates Doppler frequency corresponding to the target speed. The developed technique exhibits excellent Doppler localization, target detection and range estimation performance by overcoming the side-lobe limitations of the conventional phase coding signals in ranging applications.

关键词： Correlation Detection Doppler Frequency Golay Codes phase coding Range Estimation Quadrature phase Shift Keying Side Lobe Suppression Serial Search Frequency Banks Maximum Likelihood Estimation

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：