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A novel carrier frequency offset algorithm based on a double barker code in VDE-TER

PHYSICAL COMMUNICATION 2020年 40卷 101059-101059页

作者： Hu, Qing Jing, Xiaoyue Lu, Pengfei Sun, Qian Huang, Jianlin Dalian Maritime Univ Dalian Peoples R China China Waterborne Transport Res Inst Beijing Peoples R China

The Maritime Very High Frequency (VHF) Data Exchange System (VDES) is a basic method of data exchange in the e-Navigation strategy proposed by the International Maritime Organization (IMO). Regarding the synchronization of the VDE-terrestrial (VDE-TER) communication carrier frequency, using the special structure of the training sequence in a VDE message frame, we propose a novel carrier frequency offset (CFO) estimation algorithm based on the phase difference between the barker code and its inverse code. We derive the principle model for the barker code and anti-barker code algorithm and analyze the frequency offset estimation performance of the proposed algorithm with those of the Fitz, L&R and M&M algorithms. We also present a real-world experiment conducted using a software-defined radio (SDR) platform. The results show that in the VDE-TER channel, the double barker code (DBC) carrier frequency offset estimation algorithm has good estimation performance and estimations range within the visible range. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Very High Frequency Data Exchange System (VDES) VDE-terrestrial (VDE-TER) Carrier frequency offset (CFO) barker code Software-defined radio (SDR)

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Modified ultrasonic time-of-flight diffraction testing with barker code excitation for sizing inclined crack

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APPLIED ACOUSTICS 2018年 140卷 153-159页

作者： Han, Qingbang Wang, Peng Zheng, Hao Ho Hai Univ Coll IOT Engn Changzhou Peoples R China

Effectively sizing inclined cracks inside material is a difficult issue in ultrasonic non-destructive testing. To size the length, depth and orientation of inclined crack, a modified ultrasonic time-of-flight diffraction testing with double receivers (DR-TOFD) using barker code excitation is proposed. The DR-TOFD technique is excited by barker code, which has accurate time precision, and the diffraction wave of the crack tips is received by two receivers. The diffraction signals are compressed by matched filter to obtain desired detecting signals, which are used to estimate the length, depth and orientation of crack. Finite element method, which simulates wave propagation in specimen with a 6 mm crack with different inclination angles, is used to evaluate the detecting ability of the DR-TOFD with barker code excitation. The simulation results show that the time precision of the proposed technique is up to 0.01 mu s. Experiment is also performed to verify the detecting ability of DR-TOFD. The experiment results show that the proposed technique is able to expediently and accurately size inclined crack.

关键词： NDT TOFD Inclined crack barker code

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Ultrasound strain imaging using barker code 7

Ultrasound strain imaging using Barker code

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7th International Conference on Electronics and Information Engineering (ICEIE)

作者： Peng, Hui Tie, Juhong Guo, Dequan Chengdu Univ Informat Technol Sch Software Engn Chengdu Peoples R China Chengdu Univ Informat Technol Sch Control Engn Chengdu Peoples R China

ISBN: (数字)9781510610811

ISBN: (纸本)9781510610811

Ultrasound strain imaging is showing promise as a new way of imaging soft tissue elasticity in order to help clinicians detect lesions or cancers in tissues. In this paper, barker code is applied to strain imaging to improve its quality. barker code as a coded excitation signal can be used to improve the echo signal-to-noise ratio (eSNR) in ultrasound imaging system. For the Baker code of length 13, the sidelobe level of the matched filter output is -22dB, which is unacceptable for ultrasound strain imaging, because high sidelobe level will cause high decorrelation noise. Instead of using the conventional matched filter, we use the Wiener filter to decode the barker-coded echo signal to suppress the range sidelobes. We also compare the performance of barker code and the conventional short pulse in simulation method. The simulation results demonstrate that the performance of the Wiener filter is much better than the matched filter, and Baker code achieves higher elastographic signal-to-noise ratio (SNRe) than the short pulse in low eSNR or great depth conditions due to the increased eSNR with it.

关键词： Strain imaging elasticity imaging barker code displacement estimate

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Phase code Integration Using Interpulse Techniques for Enhanced Radar Performance

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IEEE ACCESS 2025年 13卷 51680-51692页

作者： Ahmad, Basmah Butt, Faran Awais Naqvi, Ijaz Haider Ejaz, Saqib Ali, Saqib Muqaibel, Ali Hussein Alawsh, Saleh A. Anwar, Muhammad Arif Univ Management & Technol UMT Dept Elect Engn Lahore 54770 Pakistan King Fahd Univ Petr & Minerals KFUPM Ctr Commun Syst & Sensing Dhahran 31261 Saudi Arabia Lahore Univ Management Sci LUMS Dept Elect Engn Lahore 54792 Pakistan Ctr Excellence Sci & Appl Technol CESAT Islamabad 44000 Pakistan King Fahd Univ Petr & Minerals KFUPM Elect Engn Dept Dhahran 31261 Saudi Arabia

Phase coding plays an important role in radar systems, affecting signal modulation, target detection, and interference rejection. This study assesses various phase codes, including Gold, Kasami, barker, Frank, and Chaotic codes, by analyzing performance metrics like cross-correlation and peak-to-sidelobe ratio (PSLR). The study highlights certain limitations, suggesting the need for new waveform solutions. It integrates component-based and Kronecker product-based interpulse coding to combine different codes and improve overall system performance. By merging phase codes effectively, interpulse coding leverages the strengths of individual codes to produce a composite waveform with enhanced autocorrelation and cross-correlation properties, improving radar performance. An optimization problem is formulated using a weighted performance metric to identify the best waveform, considering factors such as cross-correlation and PSLR. The approach, utilizing simple Kronecker and element-wise multiplication techniques, offers significant benefits with minimal complexity. The barker-Gold interpulse code stands out as highly effective for spread spectrum-based applications due to its favorable correlation properties.

关键词： barker code cross-correlation gold code interpulse coding Kasami code Kronecker product peak-to-side-lobe ratio phase codes barker code cross-correlation gold code interpulse coding Kasami code Kronecker product peak-to-side-lobe ratio phase codes

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Application of pulse compression technique in metal materials cracks detection with LF-EMATs

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NONDESTRUCTIVE TESTING AND EVALUATION 2023年第1期38卷 45-66页

作者： He, Min Shi, Wenze Lu, Chao Chen, Yao Zhao, Liping Dong, Dexiu Zeng, Guangdeng Nanchang Hangkong Univ Key Lab Nondestruct Testing Minist Educ Nanchang Jiangxi Peoples R China Gannan Normal Univ Key Lab Simulat & Numer Modeling Technol Jiangxi Ganzhou Peoples R China AECC Shenyang Liming Aeroengine Co LTD Prod Inspect & Testing Ctr Shenyang Peoples R China Xian Aerosp Composites Res Inst Testing & Anal Ctr Xian Peoples R China

To address the problem of low signal-to-noise ratio (SNR) and poor spatial resolution of cracks detection of the angled SV wave electromagnetic acoustic transducer (EMAT), pulse compression technique (PCT) and line-focusing technique are introduced into the angled SV wave EMAT. A finite element (FE) model of the line-focusing (LF) EMAT detection process based on the barker code excitation was established, and the effects of the design parameters of magnet and meander-line coil (MLC) on the main lobe amplitude and width of the defect echo after pulse compression were analysed. The optimal combination of LF-EMAT design parameters and excitation parameters was obtained, and it was compared with the traditional angled SV wave EMAT and the tone-burst excitation method by experimental measurements. The results shows that compared with angled SV wave EMAT with tone-burst excitation, LF-EMAT can improve the SNR by 14.9 dB with no synchronous average and be processed by PCT. The SNR from LF-EMAT with PCT is10 dB at 1.5 mm lift-off, while the SNR of the angled SV wave EMAT with tone-burst excitation is less than 0 dB at 1 mm lift-off. When the barker code PCT is applied to the LF-EMAT detection, we can achieve the purpose of increasing EMAT lift-off and reducing the synchronous averages to meet the demand of online, rapid, and high-temperature detection.

关键词： Line-Focusing EMAT barker code pulse compression technique signal-to-noise ratio spatial resolution

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Image quality improvement of magneto-acousto-electrical tomography with barker coded excitation

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BIOMEDICAL SIGNAL PROCESSING AND CONTROL 2022年第0期77卷 000-000页

作者： Deng, Dingqian Sun, Tong Yu, Linguo Chen, Yi Chen, Xin Chen, Mian Chen, Siping Lin, Haoming Shenzhen Univ Natl Reg Key Technol Engn Lab Med Ultrasound Guangdong Key Lab Biomed Measurements & Ultrasoun Sch Biomed EngnHlth Ctr Shenzhen Peoples R China

Magneto-acousto-electrical tomography (MAET) combines the advantages of the high resolution of ultrasound imaging and the high contrast of electrical impedance tomography for imaging the conductivity of tissues. The traditional MAET uses a short pulse as the excitation waveform, and the amplitude of the MAE signal for a single acquisition is very weak. Thus, the multiple-acquisition mode for averaging was adopted to reduce the system noise while significantly increasing the data acquisition time. In this study, a coded-based MAET method was proposed to improve the image quality of MAET. We theoretically derived the principle of the coded-based MAET and analyzed the performance of different pulse compression techniques. The 13-bit barker code was selected, and phantoms of different shapes and conductivity were used to verify the proposed method experimentally. Finally, in vitro experiment was conducted to investigate the performance of the proposed method in tissue level application. The experimental results show that the proposed method can significantly improve image quality and speed up the imaging time.

关键词： Magneto-acoustic-electrical tomography (MAET) barker code Coherent averaging Matched filter Wiener filter

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Minimal Peak Sidelobe Phase Sequences 42

Minimal Peak Sidelobe Phase Sequences

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42nd International Conference on Electronics and Nanotechnology

作者： Chomoborodova, N. P. Khavkina, O. M. Samoylyk, S. S. Chomoborodov, M. P. Kryvykh, Y., I Tarasenko, K., V Moroz, H., V Res & Prod Firm Sweda Ltd Zaporizhzhia Ukraine Zaporizhzhia Polytech Natl Univ Dept Machine Construct Zaporizhzhia Ukraine Zaporizhzhia Polytech Natl Univ Dept Radio Engn & Telecommun Zaporizhzhia Ukraine

ISBN: (纸本)9798350368185;9798350368178

A new method of synthesis of code sequences for binary phase manipulation is proposed. One of the phase angles was optimized by solving the system of nonlinear equations. New code sequences were synthesized, and new phase sequences were constructed on their basis, which ensure the minimum level of the side lobes of the autocorrelation function. The results of the statistical analysis are given and the detection characteristics are calculated. The practical novelty of obtained results is in the expansion of the set of barker code sequences.

关键词： phase code-manipulated signal barker code autocorrelation function sidelobe level

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An Adaptive Peak Detection Method for Inspection of Breakages in Long Rails by Using barker coded UGW

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IEEE ACCESS 2020年 8卷 48529-48542页

作者： Wei, Xiaoyuan Yang, Yuan Urena, Jesus Yan, Jiaxuan Wang, Haozhen Xian Univ Technol Dept Elect Engn Xian 710048 Peoples R China Shaanxi Key Lab Complex Syst Control & Intelligen Xian 710048 Peoples R China Univ Alcala Dept Elect Alcala De Henares 28805 Spain

For a broken rail detection system based on ultrasonic guided waves (UGW), the multimodal and dispersion of UGW degrade signal-to-noise ratio (SNR) and range resolution. To improve SNR of the received signals and range resolution, the pulse compression technique based on 13-bit barker code is presented in this work. Through a PSpice model of the pitch-catch setup, as well as performing field tests, it is shown that coded UGW signals can efficiently improve SNR by 5 dB and have strong noise immunity. As the detection distance increases, the mainlobe width increases linearly while the sidelobe peak levels remain basically unchanged. In addition, to correctly and quickly identify the corresponding transmissions at the receivers, an adaptive peak detection algorithm is proposed, which is based on a digital bandpass tracking filter, moving averaging filters and Hilbert transform. By using some field tests under different detection distances, it is found that compared to the previous works, the proposed adaptive peak detection algorithm has stronger robustness and better anti-noise performance. In addition, the proposed method is easy to integrate into a real-time detection system by proper software design.

关键词： Rails Signal to noise ratio Acoustics Ultrasonic transducers Encoding Transforms SPICE Peaks detection barker code pulse compression long rail breakages detection UGW

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Carrier frequency offset estimation for MIMO single-carrier FDMA system in wireless communication

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ALEXANDRIA ENGINEERING JOURNAL 2022年第9期61卷 6907-6917页

作者： Badran, Ehab F. F. Samara, Marwa Ismail, Nour Eldin Arab Acad Sci Technol & Maritime Dept Elect & Commun Engn Coll Engn & Technol Alexandria 21937 Egypt Alexandria Higher Inst Engn & Technol AIET Dept Elect Engn Alexandria 21311 Egypt Alexandria Univ Dept Elect Engn Alexandria 21544 Egypt

Multiple-Input Multiple-Output (MIMO) Orthogonal Frequency-Division Multiplexing (OFDM) systems and Single-Carrier Frequency-Division Multiple Access (SC-FDMA) are so susceptible to carrier frequency offset (CFO) between transceivers. In this paper, a novel sequence called CAZBAR is proposed. The proposed CAZBAR sequence is based on constant amplitude zero autocorrelation (CAZAC) sequence and barker code. CAZBAR sequence shows better auto correlation with higher peak at zero shift without ripples, which facilitates estimating carrier frequency offset in communication systems compared to other compensation methods in terms of mean square error (MSE). By applying CAZBAR sequence in MIMO SC-FDMA system 2 x 2 and 4x4, the bit error rate (BER) performance has improved significantly. At a BER=10(-2), a SNR reduction of 11 dB is achieved for 2 x 2 system and 7 dB reduction for 4 x 4 system compared to other sequences. Which improves the performance of the whole system MIMO SC-FDMA. The CAZBAR sequence can be applied in 5G techniques, MIMO-OFDM, and MIMO SC-FDMA systems.(c) 2021 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： CAZAC sequence barker code Frequency offset compensation MIMO SC-FDMA

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Design and Fabrication of barker coded Surface Acoustic Wave (SAW) Correlator at 2.45 GHz for Low-Power Wake-up Receivers

Design and Fabrication of Barker Coded Surface Acoustic Wave...

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German Microwave Conference (GeMiC)

作者： Ballandras, Sylvain Abughannam, Saed Courjon, Emilie Scheytt, J. Christoph Frec N Sys SASU Besancon France Paderborn Univ Heinz Nixdorf Inst Dept Syst & Circuit Technol Paderborn Germany

ISBN: (纸本)9783982039718

Low-power receivers use direct-detection receiver architecture for its design simplicity and its low power dissipation. However, the direct-detection based receivers suffer from co-channel interference which significantly degrades the communication reliability. Co-channel interference robustness can be improved by using a BPSK barker code modulated Surface Acoustic Wave (SAW) correlator as a prior stage to the RF direct detection circuit. This paper reports in details the design, fabrication and measurements of a 2.45 GHz SAW correlator with 13 bits length barker code. The device is fabricated on Lithium Niobate LiNbO3 substrate and it is composed of an input non-coded Inter Digital Transducers (IDT), a Piezoelectric substrate and an output coded IDT. The device wavelength lambda is set to 1.6 am, considering a phase velocity of the wave equal to 3970 m.s-1. Several configurations of the device were designed and fabricated, particularly varying the aperture and the non-coded IDT length to find out the optimal device configuration. All devices were found to operate with Insertion Loss (IL) ranging from 12 to 15 dB at 2.45 GHz with a tip probing measurement setup, while a packaged sample has an IL of 12.45 dB at 2.44 GHz mounted on a PCB with external 50 SI LC matching network Additionally, time-domain measurement for the packaged device shows that the output has a correlation peak with a peak-to-side-lobe (PSL) ratio of 4:1 for a -0.5 dBm input BPSK barker code signal.

关键词： Low-power WuRx SAW Correlator direct-detection barker code Wireless Sensor Networks

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