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A Time Domain Synthesized Binary Phase Code sidelobe suppression Filter Based on Genetic Algorithm

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A Time Domain Synthesized Binary Phase Code Sidelobe Suppres...

THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR sidelobe suppression IN MB-OFDM COGNITIVE RADIOS

2000年第16届世界计算机大会

作者： Liping ZHANG Xiutan WANG Yong HUANG Yingning PENG Department of Electronic Engineering Tsinghua University

＜正＞Binary phase coded waveform（BPCW） is widely used in tracking radars,while the sidelobe suppression filter（SSF） designing methods for BPCW are always limited to short codes such as Barker code. A new kind of SSF based on time domain synthesis and genetic algorithm（GA） is *** filter can be used for various lengthed codes,including the m-sequence *** simulation results of time domain synthesized SSF for the Barker codes and resequence codes are given,with comments on the performance comparison of the new filter with some known filters.

关键词： Binary phase coded waveform sidelobe suppression radar pulse compression Genetic Algorithm(GA)

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THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE ...

W-Band High-Efficiency Waveguide Slot Array Antenna with Low sidelobe Levels Based on Silicon Micromachining Technology

2009 IEEE International Conference on Communication Technology and Applications（ICCTA2009）

作者： Zhigang Xu Cheng Yang Weixia Zou Zheng Zhou Key Lab of Universal Wireless Communications MOE Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

＜正＞From the mathematic expression,we can see that sidelobe power of multi-band orthogonal frequency-division multiplexing（MB-OFDM） signal is a function of the data symbols loaded on the *** the derivation of the minimum of the function,relationships among data symbols, which help to suppress sidelobes,are *** types of methods,referred as Sub-carrier Adding（SA） method and Sub-carrier Multiplying（SM） method, are proposed,which realize the relationships at the cost of small degradation in information transmission *** a result,with the proposed methods,the sidelobe power can be *** results also prove this.

关键词： OFDM sidelobe suppression data symbols relationships

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Chinese Journal of Electronics 2022年第4期31卷 665-673页

作者： YAO Shisen CHENG Yujian BAI Hang FAN Yong University of Electronic Science and Technology of China

A high-efficiency waveguide slot array antenna with low sidelobe level(SLL) is investigated for W-band applications. The silicon micromachining technology is utilized to realize multilayer antenna architecture by three key steps of selective etching, gold plating and Au-Au bonding. The radiating slot based on this technique becomes thick with a minimum thickness of 0.2 mm and accompanies with the decrease of slot's radiation ability. To overcome this weakness, a stepped radiation cavity is loaded on the slot. The characteristic of cavityloaded slot is investigated to synthesize the low-SLL array antenna. The unequal hybrid corporate feeding network is constructed to achieve sidelobe suppression in the E-plane. A pair of 16 × 8 low-SLL and high-effciency slot arrays is fashioned and confirmed experimentally. The bandwidth with the radiation effciency higher than 80% is92.3–96.3 GHz. The SLLs in both E-and H-planes are below-19 d B.

关键词： Antenna accessories slot antenna arrays radiation cavity low sidelobe level micromachining W-band high efficiency waveguide slot array antenna silicon Surface treatment (semiconductor technology) Antenna arrays Fabrication of MEMS and NEMS devices high effciency slot arrays low-SLL array antenna antenna radiation patterns W-band applications sidelobe suppression high-effciency slot arrays etching radiating slot Au-Au bonding radiation effciency silicon micromachining technology planar antenna arrays antenna feeds gold multilayer antenna architecture

Low sidelobe robust imaging in random frequency-hopping wideband radar based on compressed sensing

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Journal of Central South University 2013年第3期20卷 702-714页

作者：刘振魏玺章黎湘 School of Electronic Science and Engineering National University of Defense Technology

High resolution range imaging with correlation processing suffers from high sidelobe pedestal in random frequency-hopping wideband radar. After the factors which affect the sidelobe pedestal being analyzed, a compressed sensing based algorithm for high resolution range imaging and a new minimized ll-norm criterion for motion compensation are proposed. The random hopping of the transmitted carrier frequency is converted to restricted isometry property of the observing matrix. Then practical problems of imaging model solution and signal parameter design are resolved. Due to the particularity of the proposed algorithm, two new indicators of range profile, i.e., average signal to sidelobe ratio and local similarity, are defined. The chamber measured data are adopted to testify the validity of the proposed algorithm, and simulations are performed to analyze the precision of velocity measurement as well as the performance of motion compensation. The simulation results show that the proposed algorithm has such advantages as high precision velocity measurement, low sidelobe and short period imaging, which ensure robust imaging for moving targets when signal-to-noise ratio is above 10 dB.

关键词： random frequency-hopping radar high resolution range profile sidelobe suppression motion compensation compressed sensing

An extended chirp scaling algorithm for spaceborne sliding spotlight synthetic aperture radar imaging

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Chinese Journal of Aeronautics 2014年第4期27卷 892-902页

作者： Guo Jiao Xu Youshuan Fu Longsheng College of Mechanical and Electronic Engineering Northwest A&F University Shanghai Institute of Satellite Engineering

A system impulse response with low sidelobes is critical in synthetic aperture radar（SAR） images because sidelobes contribute to noise and interfere with nearby scatterers. However,the conventional tricks of sidelobe suppression are unable to be exactly applied to the case of spaceborne sliding spotlight SAR due to great azimuth shifts in both time and frequency domains. In this paper, an extended chirp scaling algorithm is presented for spaceborne sliding spotlight SAR data imaging. The proposed algorithm firstly uses the spectral analysis（SPECAN） technique to avoid the azimuth spectrum folding effect and then employs the chirp scaling（CS） algorithm to achieve data focusing, i.e., the so-called two-step approach. To suppress the sidelobe level, an efficient strategy for the azimuth spectral weighting which only involves matrix multiplications and short fast Fourier transformations（FFTs） is proposed, which is a post-process executed on the focused SAR image and particularly simple to be implemented. The SAR image processed by the proposed extended CS algorithm is very precise and perfectly phase-preserving. In the end, computer simulation results verify the analysis and confirm the validity of the proposed algorithm.

关键词： Chirp scaling (CS) sidelobe suppression Sliding spotlight Spectral analysis (SPECAN) Synthetic aperture radar(SAR)

Performance Analysis of N-Continuous OFDM Systems with Low-Interference Signal

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China Communications 2022年第11期19卷 209-230页

作者： Peng Wei Yue Xiao Shuxia Yan Wei Xiang School of Electronics and Information Engineering Tiangong UniversityTianjin 300387China Tianjin Key Laboratory of Photoelectric Detection Technology and System Tiangong UniversityTianjin 300387China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China School of Engineering and Mathematical Sciences La Trobe UniversityMelbourneVIC 3086Australia

N-continuous orthogonal frequency division multiplexing(NC-OFDM)is a promising multicarrier transmission waveform conceived for improving sidelobe suppression *** reduce the severe inband interference in traditional NC-OFDM,we have proposed low-interference signal modeling for ***,spectral leakage and error may be undesirably increased owing to the limited continuous differentiability of the smooth *** this paper,the low-interference scheme is investigated in terms of power spectrum density(PSD)and error performance,under the parameters of the highest derivative order(HDO)and the length of the smooth signal,to prove and quantify its advantages over traditional *** the context of PSD,sidelobe decay is evaluated upon considering two discontinuous points due to the finite continuity of the smooth signal and its higher-order ***,it was shown that the low-interference scheme incurs small signal-to-noise ratio(SNR)loss and bit error rate(BER)for a short length of the smooth signal or a small HDO compared to traditional ***,due to the cyclostationarity loss imposed by the smooth signal,an effective solution is suggested for the time synchronization in a practical *** on analyses and simulation results,the trade offs between sidelobe suppression and BER are studied.

关键词： BER low-interference N-continuous OFDM PSD sidelobe suppression

A Novel 2-D Signal Processing Scheme for Quasi-Random Step Frequency Signal

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Journal of Systems Engineering and Electronics 2003年第3期14卷 77-80页

作者：位寅生刘永坦许荣庆 Research Institute of Electronic Engineering Harbin Institute of Technology Harbin 150001 P.R.China

Due to the heavy congestion in HF bands, HF radars are restricted to operating within narrow frequency bands. To improve the system bandwidth and avoid heavy interference bands, a quasi-random step frequency signal with discontinuous bands is presented. A novel two-dimensional signal processing scheme for this signal is proposed on the basis of delicate signal analysis. Simulation results demonstrate that the scheme could successfully realize the resolutions by decoupling the range-Doppler ambiguity, and effectively suppress the maximal sidelobe. Moreover, the scheme is simple and has good numerical stability.

关键词： Random step frequency sidelobe suppression Signal processing.

A Low-Interference Time-Domain N-Continuous OFDM Scheme

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China Communications 2016年第S2期13卷 150-158页

作者： Peng Wei Lilin Dan Yue Xiao Xia Lei Shaoqian Li National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China National Mobile Communications Research Laboratory Southeast University

N-continuous orthogonal frequency division multiplexing(NC-OFDM) is an outstanding method to suppress sidelobe for baseband OFDM signals in future 5G wireless ***,the precoder of NCOFDM usually causes severe interference and high *** alleviate these problems,this paper proposes an improved time-domain N-continuous OFDM(TD-NC-OFDM) by optimizing the smooth signal,which is the linear combination of rectangularly pulsed OFDM basis signals truncated by a smooth ***,we show that the proposed scheme is with lower transceiver complexity and notable performance gain in signal-tointerference-plus-noise ratio(SINR).Lastly,simulation results show that the proposed low-interference TD-NC-OFDM can achieve similar sidelobe suppression performance,with negligible bit-error rate(BER) degradation,compared to conventional NC-OFDM.

关键词： orthogonal frequency division multip-lexing(OFDM) sidelobe suppression N-continuous OFDM(NC-OFDM)

A Novel Wavenumber Domain SAR Imaging Algorithm Based on the Fractional Fourier Transform

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Chinese Journal of Electronics 2014年第4期23卷 866-870页

作者： XU Huaping XIAO Zhongyuan GAO Jing LI Chunsheng Department of Electronic and Information Engineering Beihang University

The conventional Wavenumber domain algorithm(WDA) employs Fast Fourier transform(FFT) to implement matched filter. It is characterized by its high precision SAR imaging. Compared with FFT, Fractional Fourier transform(Fr FT) can provide lower and narrower sidelobes when it is applied to compress chirp signals at the optimal transform. This paper proposed a novel SAR imaging algorithm, termed Fr WDA which replaces FFT in WDA with Fr FT. The Fr WDA was derived and its implementation was presented. How to choose the optimal transformation order was given subsequently. The Fr WDA preserves high precision focusing, and has better performance on sidelobe suppression. The Fr WDA is more suitable for the high precision SAR imaging, especially in target detection and recognition. Simulation results demonstrate that Fr WDA provides better performance on focusing and sidelobe suppression compared with the classical FFT-based WDA.

关键词： SAR imaging Wavenumber domain algorithm FFT Fractional Fourier transform sidelobe suppression