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基于激光调频连续波正反向调谐色散对消方法 被引量:3
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作者 许新科 龙康 +6 位作者 徐靖翔 赵军 王道档 刘璐 刘维 郭天太 孔明 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2021年第2期243-247,共5页
为了减小宽带激光调频连续波测量中的色散失配效应,提出了一种外腔可调谐激光器正、反向调谐消除色散失配的方法。当外腔可调谐激光器与光纤光路结合时,系统将产生色散失配效应,表现为目标信号的谱峰展宽和峰值偏移,测距值随调谐带宽增... 为了减小宽带激光调频连续波测量中的色散失配效应,提出了一种外腔可调谐激光器正、反向调谐消除色散失配的方法。当外腔可调谐激光器与光纤光路结合时,系统将产生色散失配效应,表现为目标信号的谱峰展宽和峰值偏移,测距值随调谐带宽增加而变化,导致测量不稳定。为了解决这一问题,研究了外腔可调谐激光器正、反向调谐时的系统色散失配特性,结果表明,在正反向扫频时色散趋势具有对称分布的特点,建立了正反向扫频系统色散失配模型,在此基础上提出通过外腔激光器正、反向调谐实现色散对消。该方法不需要预先标定系统的色散系数,也不需要循环迭代补偿,单次测量即可完成系统色散补偿,从而为提高色散补偿效率提供了一种思路。 展开更多
关键词 光学 激光调频连续波(frequency modulated continuous wave FMCW) 激光测距 色散补偿 外腔可调谐激光器
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Range Ambiguity Elimination in a Short-Range FMCW Radar System 被引量:1
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作者 魏国华 吴嗣亮 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期201-204,共4页
Modified implementation architecture for sinusoidal frequency modulation is introduced to extract the range information from the received radar echo. Range ambiguity problem arises because the range is calculated from... Modified implementation architecture for sinusoidal frequency modulation is introduced to extract the range information from the received radar echo. Range ambiguity problem arises because the range is calculated from the estimated phase of the received signal which is wrapped into (0, 2π]. By integrating Doppler frequency shifts, the variation of range can be estimated and used as an auxiliary information to help eliminating the corresponding range ambiguity. The performance of the new technique is evaluated by simulations. The results show that this technique is robust to sever phase noise and can be used effectively for ambiguity elimination of the modified sinusoidal frequency modulated continuous wave radar. 展开更多
关键词 range ambiguity mitigation frequency modulated continuous wave radar Doppler frequency
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High-Precision Vital Signs Detection Method Based on Spectrum Refinement and Extended DCMA
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作者 Mingxu Xiang Wu Ren +1 位作者 Weiming Li Zhenghui Xue 《Journal of Beijing Institute of Technology》 EI CAS 2022年第1期101-111,共11页
In this paper,the spectral estimation algorithm is extended to the detection of human vi-tal signs by mm-wave frequency modulated continuous wave(FMCW)radar,and a comprehensive algorithm based on spectrum refinement a... In this paper,the spectral estimation algorithm is extended to the detection of human vi-tal signs by mm-wave frequency modulated continuous wave(FMCW)radar,and a comprehensive algorithm based on spectrum refinement and the extended differentiate and cross multiply al-gorithm(DCMA)has been proposed.Firstly,the improved DFT algorithm is used to accurately obtain the distance window of human body.Secondly,phase ambiguity in phase extraction is avoided based on extended DCMA algorithm.Then,the spectrum range of refinement is determ-ined according to the peak position of the spectrum,and the respiratory and heartbeat frequency information is obtained by using chirp z-transform(CZT)algorithm to perform local spectrum re-finement.For verification,this paper has simulated the radar echo signal modulated by the simu-lated cardiopulmonary signal according to the proposed algorithm.By recovering the simulated car-diopulmonary signal,the high-precision respiratory and heartbeat frequency have been obtained.The results show that the proposed algorithm can effectively restore human breathing and heart-beat signals,and the relative error of frequency estimation is basically kept below 1.5%. 展开更多
关键词 vital signs detection frequency modulated continuous wave(FMCW)radar frequency spectrum refinement high-precision frequency estimation
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