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Animal personalities and their implications for complex signaling
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作者 Nicholas DIRIENZO Ann V HEDRICK 《Current Zoology》 SCIE CAS CSCD 2014年第3期381-386,共6页
Animal personalities have been a major focus of behavioral ecology over the past decade. Consistent individual dif ferences in behavior have been found across taxa, and have been shown to influence a range of ecologic... Animal personalities have been a major focus of behavioral ecology over the past decade. Consistent individual dif ferences in behavior have been found across taxa, and have been shown to influence a range of ecological processes. The role of personalities in sexual selection has been considered, and examples exist that show selection for personality traits with both assortative and disassortative mating patterns between personality types. One overlooked aspect of the personality and sexual se lection literature is the potential for personalitysignaling interactions, specifically with complex signaling. Complex signaling is a diverse topic in itself, and in short, consists of multiple signals within one or more modalities that interact to elicit a receiver response. Research into complex signaling has been thorough, although at times studies discover complex signaling systems that fail to fit into one of the existing hypotheses in the literature. Here, we argue that personalities may interact with complex signal ing, which should be considered by researchers of both personality and sexual selection and communication. We describe several ways in which personalitycomplex signaling interactions could affect both the signaler and receiver, and the way in which they may drive personalityspecific signals as well as receiver preferences. Finally, we discuss how considering personality in com plex signaling studies may inform theory as well as improve the ability of researchers to accurately describe its function. 展开更多
关键词 Animal Personalities Sexual Selection complex signaling Multimodal Communication COMMUNICATION
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Analysis on Design of Kohonen-network System Based on Classification of Complex Signals 被引量:1
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作者 YOU Rong yi, XU Shen chu (Dept. of Phys., Xiamen University, Xiamen 361005, CHN) 《Semiconductor Photonics and Technology》 CAS 2002年第3期174-178,185-192,共7页
The key methods of detection and classification of the electroencephalogram(EEG) used in recent years are introduced . Taking EEG for example, the design plan of Kohonen neural network system based on detection and cl... The key methods of detection and classification of the electroencephalogram(EEG) used in recent years are introduced . Taking EEG for example, the design plan of Kohonen neural network system based on detection and classification of complex signals is proposed, and both the network design and signal processing are analyzed, including pre-processing of signals, extraction of signal features, classification of signal and network topology, etc. 展开更多
关键词 complex signal CLASSIFICATION of signal KOHONEN NEURAL network
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ASYMPTOTIC PROPERTY STUDY OF THE LEAST SQUARE ESTIMATES OF 2-D EXPONENTIAL SIGNALS VIA COMPLEX SIGNAL PROCESSING APPROACH 被引量:1
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作者 Mao Yongcai Bao Zheng (Key Laboratory for Radar Signal Processing, Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 1999年第1期1-6,共6页
By use of the approach of complex random signal processing, the asymptotic statistical properties of the least square estimates of 2-D exponential signals are studied. In doing so it is found that the representation i... By use of the approach of complex random signal processing, the asymptotic statistical properties of the least square estimates of 2-D exponential signals are studied. In doing so it is found that the representation is considerably more intuitive, and is analytically more tractable. 展开更多
关键词 2-D complex EXPONENTIAL signalS Least SQUARES ESTIMATES ASYMPTOTIC STATISTICAL properties
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Blind source separation algorithm for communication complex signals in communication reconnaissance
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作者 Weihong FU Xiaoniu YANG +1 位作者 Nai’an LIU Xingwen ZENG 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2008年第3期338-342,共5页
Most blind source separation algorithms are only applicable to real signals,while in communication reconnaissance processed signals are complex.To solve this problem,a blind source separation algorithm for communicati... Most blind source separation algorithms are only applicable to real signals,while in communication reconnaissance processed signals are complex.To solve this problem,a blind source separation algorithm for communication complex signals is deduced,which is obtained by adopting the Kullback-Leibler divergence to measure the signals’independence.On the other hand,the performance of natural gradient is better than that of stochastic gradient,thus the natural gradient of the cost function is used to optimize the algorithm.According to the conclusion that the signal’s mixing matrix after whitening is orthogonal,we deduce the iterative algorithm by constraining the separating matrix to an orthogonal matrix.Simulation results show that this algorithm can efficiently separate the source signals even in noise circumstances. 展开更多
关键词 communication reconnaissance blind source separation complex signal
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A Complex Signal
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作者 YAN WEI 《Beijing Review》 2007年第20期21-21,共1页
The removal of Taiwan from the common strategic objectives of the U.S.-Japan alliance could mean much more than a change of wording While U.S.and Japanese top diplomats and defense officials celebrated closer cooperat... The removal of Taiwan from the common strategic objectives of the U.S.-Japan alliance could mean much more than a change of wording While U.S.and Japanese top diplomats and defense officials celebrated closer cooperation forged by their annual meeting 展开更多
关键词 A complex signal
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A new complex Duffing oscillator used in complex signal detection 被引量:10
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作者 DENG XlaoYing LIU HaiBo LONG Teng 《Chinese Science Bulletin》 SCIE CAS 2012年第17期2185-2191,共7页
In view of the fact that complex signals are often used in the digital processing of certain systems such as digital communication and radar systems,a new complex Duffing equation is proposed.In addition,the dynamical... In view of the fact that complex signals are often used in the digital processing of certain systems such as digital communication and radar systems,a new complex Duffing equation is proposed.In addition,the dynamical behaviors are analyzed.By calculating the maximal Lyapunov exponent and power spectrum,we prove that the proposed complex differential equation has a chaotic solution or a large-scale periodic one depending on different parameters.Based on the proposed equation,we present a complex chaotic oscillator detection system of the Duffing type.Such a dynamic system is sensitive to the initial conditions and highly immune to complex white Gaussian noise,so it can be used to detect a weak complex signal against a background of strong noise.Results of the Monte-Carlo simulation show that the proposed detection system can effectively detect complex single frequency signals and linear frequency modulation signals with a guaranteed low false alarm rate. 展开更多
关键词 信号检测 DUFFING方程 振荡器 LYAPUNOV 复域 雷达系统 线性调频信号 检测系统
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Gamma-aminobutyric acid A receptors in Alzheimer's disease: highly localized remodeling of a complex and diverse signaling pathway 被引量:4
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作者 Andrea Kwakowsky Beatriz Calvo-Flores Guzman +2 位作者 Karan Govindpani Henry J. Waldvogel Richard L. Faull 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第8期1362-1363,共2页
Alzheimer's disease (AD), the predominant form of dementia, is a chronic, incurable neurodegenerative disorder presenting with symptoms includ- ing progressive memory loss and disturbed emotional state. It has been... Alzheimer's disease (AD), the predominant form of dementia, is a chronic, incurable neurodegenerative disorder presenting with symptoms includ- ing progressive memory loss and disturbed emotional state. It has been estimated that dementia affects over 47 million people worldwide (Prince et al., 2015), and with 60-80% of cases attributable to AD. 展开更多
关键词 AD highly localized remodeling of a complex and diverse signaling pathway Gamma-aminobutyric acid A receptors in Alzheimer’s disease
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Radar Emitter Signal Recognition Based on Complexity Features 被引量:18
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作者 张葛祥 金炜东 胡来招 《Journal of Southwest Jiaotong University(English Edition)》 2004年第2期116-122,共7页
Intra-pulse characteristics of different radar emitter signals reflect on signal waveform by way of changing frequency, phase and amplitude. A novel approach was proposed to extract complexity features of radar emitte... Intra-pulse characteristics of different radar emitter signals reflect on signal waveform by way of changing frequency, phase and amplitude. A novel approach was proposed to extract complexity features of radar emitter signals in a wide range of signal-to-noise ratio (SNR), and radial basis probability neural network (RBPNN) was used to recognize different radar emitter signals. Complexity features, including Lempel-Ziv complexity (LZC) and correlation dimension (CD), can measure the complexity and irregularity of signals, which mirrors the intra-pulse modulation laws of radar emitter signals. In an experiment, LZC and CD features of 10 typical radar emitter signals were extracted and RBPNN was applied to identify the 10 radar emitter signals. Simulation results show that the proposed approach is effective and has good application values because average accurate recognition rate is high when SNR varies in a wide range. 展开更多
关键词 signal processing Lempel-Ziv complexity Correlation dimension Radar emitter signals
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Identifying influential nodes based on graph signal processing in complex networks 被引量:1
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作者 赵佳 喻莉 +1 位作者 李静茹 周鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期639-648,共10页
Identifying influential nodes in complex networks is of both theoretical and practical importance. Existing methods identify influential nodes based on their positions in the network and assume that the nodes are homo... Identifying influential nodes in complex networks is of both theoretical and practical importance. Existing methods identify influential nodes based on their positions in the network and assume that the nodes are homogeneous. However, node heterogeneity (i.e., different attributes such as interest, energy, age, and so on ) ubiquitously exists and needs to be taken into consideration. In this paper, we conduct an investigation into node attributes and propose a graph signal pro- cessing based centrality (GSPC) method to identify influential nodes considering both the node attributes and the network topology. We first evaluate our GSPC method using two real-world datasets. The results show that our GSPC method effectively identifies influential nodes, which correspond well with the underlying ground truth. This is compatible to the previous eigenvector centrality and principal component centrality methods under circumstances where the nodes are homogeneous. In addition, spreading analysis shows that the GSPC method has a positive effect on the spreading dynamics. 展开更多
关键词 complex networks graph signal processing influential node identification
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泻痢康胶囊介导肠道菌群调控TNFR1/RIP1/ComplexⅠ信号通路治疗HIV/AIDS腹泻的机制探析
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作者 姜琦 许前磊 +2 位作者 郭会军 桑锋 李鹏宇 《中华中医药杂志》 CAS CSCD 北大核心 2024年第8期4272-4276,共5页
艾滋病腹泻是艾滋病患者常见的临床并发症,其病程长、缠绵难愈,严重影响了此类患者的工作与生活。艾滋病腹泻的发生与异常分泌的TNF-α激活RIP1/ComplexⅠ通路、肠黏膜屏障受损,菌群结构失衡相关。泻痢康胶囊能调节TNF-α分泌,修复肠黏... 艾滋病腹泻是艾滋病患者常见的临床并发症,其病程长、缠绵难愈,严重影响了此类患者的工作与生活。艾滋病腹泻的发生与异常分泌的TNF-α激活RIP1/ComplexⅠ通路、肠黏膜屏障受损,菌群结构失衡相关。泻痢康胶囊能调节TNF-α分泌,修复肠黏膜屏障,调节菌群结构,减少CD_(4)^(+)T淋巴细胞的持续耗损,促进免疫机能修复。文章浅析泻痢康胶囊治疗艾滋病腹泻的作用机制,以期丰富其科学内涵。 展开更多
关键词 泻痢康胶囊 艾滋病相关腹泻 肠道菌群 TNFR1/RIP1/complexⅠ信号通路
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Arbitrary-Dimensional Frequency Estimation of Complex Sinusoid Signals
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作者 Zhang Zhan College of Electronic Information, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第4期57-60,共4页
The problem of increasing computation in pace with the growth of dimension is discussed for arbitrary dimensional frequency estimation of complex sinusoid signals. The conception of matrix core, the form of which do... The problem of increasing computation in pace with the growth of dimension is discussed for arbitrary dimensional frequency estimation of complex sinusoid signals. The conception of matrix core, the form of which doesnt change with dimension, is put forward. The deduced estimation formula shows that a N dimensional frequency estimation could be obtained by N one dimensional calculations. Obviously, while dimension increases, this method could reduce much computation. 展开更多
关键词 complex sinusoid signal matrix core MLE
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WIDELY LINEAR RLS CONSTANT MODULUS ALGORITHM FOR COMPLEX-VALUED NONCIRCULAR SIGNALS 被引量:1
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作者 Zhang Ting Wang Bin Liu Shigang 《Journal of Electronics(China)》 2014年第5期416-426,共11页
Based on the constant modulus criterion, a new Widely Linear(WL) blind equalizer and a novel widely linear recursive least square constant modulus algorithm are proposed to improve the blind equalization performance f... Based on the constant modulus criterion, a new Widely Linear(WL) blind equalizer and a novel widely linear recursive least square constant modulus algorithm are proposed to improve the blind equalization performance for complex-valued noncircular signals. The new algorithm takes advantage of the WL filtering theory by taking full use of second-order statistical information of the complex-valued noncircular signals. Therefore, the weight vector contains the complete second-order information of the real and imaginary parts to decrease the residual inter-symbol interference effectively. Theoretical analysis and simulation results show that the proposed scheme can significantly improve the equalization performance for complex-valued noncircular signals compared with traditional blind equalization algorithms. 展开更多
关键词 complex-valued noncircular signals Blind equalization Widely Linear(WL) filtering Constant modulus
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Estimation of the complex frequency of a harmonic signal based on a linear least squares method
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作者 He Meilin Xiu Yanxia 《Geodesy and Geodynamics》 2015年第3期220-225,共6页
In this study, we propose a simple linear least squares estimation method(LLS) based on a Fourier transform to estimate the complex frequency of a harmonic signal. We first use a synthetically-generated noisy time ser... In this study, we propose a simple linear least squares estimation method(LLS) based on a Fourier transform to estimate the complex frequency of a harmonic signal. We first use a synthetically-generated noisy time series to validate the accuracy and effectiveness of LLS by comparing it with the commonly used linear autoregressive method(AR). For an input frequency of 0.5 m Hz, the calculated deviations from the theoretical value were 0.004‰and 0.008‰ for the LLS and AR methods respectively; and for an input 5 10 6attenuation,the calculated deviations for the LLS and AR methods were 2.4% and 1.6%. Though the theory of the AR method is more complex than that of LLS, the results show LLS is a useful alternative method. Finally, we use LLS to estimate the complex frequencies of the five singlets of the0S2 mode of the Earth’s free oscillation. Not only are the results consistent with previous studies, the method has high estimation precisions, which may prove helpful in determining constraints on the Earth’s interior structures. 展开更多
关键词 Harmonic signal complex frequency Least squares es
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Polyubiquitination and Proteasome Signals in Tubulobulbar Complexes of Rat Late Spermatids
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作者 Manaka Akashi Sadaki Yokota Hideaki Fujita 《CellBio》 2013年第4期173-178,共6页
To illustrate the involvement of tubulobulbar complexes (TBC) in ubiquitin-proteasome degradation of unnecessary proteins in the head cytoplasm of late spermatids, the localization of polyubiquitin and proteasome was ... To illustrate the involvement of tubulobulbar complexes (TBC) in ubiquitin-proteasome degradation of unnecessary proteins in the head cytoplasm of late spermatids, the localization of polyubiquitin and proteasome was studied by immunofluorescence and immunoelectron microscopy. Polyubiquitin localized to TBC and proteasome subunit α to dense materials surrounding the TBC in the cytoplasm of Sertoli cell enwrapping sickle-shaped spermatid heads. The results suggest that the TBC is a structural device for ubiquin-proteasome degradation of unnecessary proteins in the cytoplasm of spermatid head during rapid reduction of the head cytoplasm and nuclear compaction of late spermatids. 展开更多
关键词 Tubulobulbar complex POLYUBIQUITIN signalS PROTEASOME Immunoelectron Microscopy
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Mathematical theory of signal analysis vs. complex analysis method of harmonic analysis
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作者 QIAN Tao ZHANG Li-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第4期505-530,共26页
We present recent work of harmonic and signal analysis based on the complex Hardy space approach.
关键词 Mobius transform Blaschke form mono-component Hardy space adaptive Fourier decomposi-tion rational approximation rational orthogonal system time-frequency distribution digital signal processing uncertainty principle higher dimensional signal analysis in several complex variables and the Clifford algebrasetting.
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SM系统中改进的低复杂度检测算法
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作者 赵冠男 杨若琳 +2 位作者 张菀书 杨晓晖 田勇 《现代电子技术》 北大核心 2025年第17期16-20,共5页
在空间调制(SM)技术中,最大似然(ML)检测算法通过遍历所有可能的情况获得最优的解调结果,该算法利用高计算复杂度换取最优的检测性能,因而ML算法不适用于大规模SM系统。为此,在保证检测性能的前提下降低计算复杂度,提出QC-ML检测算法。... 在空间调制(SM)技术中,最大似然(ML)检测算法通过遍历所有可能的情况获得最优的解调结果,该算法利用高计算复杂度换取最优的检测性能,因而ML算法不适用于大规模SM系统。为此,在保证检测性能的前提下降低计算复杂度,提出QC-ML检测算法。该算法首先将接收信号进行预处理,利用圆形边界量化方法缩小每根可能发送天线的调制星座符号搜索空间,在缩小后的搜索空间中选出ML值最小的一组结果输出。由于量化的主要思想为比较大小,因此在该过程中不会引入额外的计算复杂度。通过仿真分析可知,改进算法的检测性能与原算法接近,而计算复杂度大大降低,验证了所提算法的有效性。 展开更多
关键词 空间调制 信号检测 最大似然 计算复杂度 量化 检测性能
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复杂动态电能信号的游程域特征分析理论与建模
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作者 王学伟 吴迪 +2 位作者 袁瑞铭 李文文 王国兴 《电网技术》 北大核心 2025年第4期1617-1624,共8页
针对国内外新型电力系统建设中,复杂动态电能计量信号强随机性导致电能计量严重超差问题,提出了复杂动态电能计量信号的游程域特征分析与特征建模理论,分析游程域重要特征对电能表误差的影响。首先,构建复杂动态电能信号的随机参量模型... 针对国内外新型电力系统建设中,复杂动态电能计量信号强随机性导致电能计量严重超差问题,提出了复杂动态电能计量信号的游程域特征分析与特征建模理论,分析游程域重要特征对电能表误差的影响。首先,构建复杂动态电能信号的随机参量模型;其次,提出一种复杂动态电流幅度序列映射到游程域的理论方法;构建游程域特征参量,提取电流快速变化局部特征;构建特征函数,提取电流随机变化全局特征;然后,提出一种复杂动态电能信号多特征约束模型、模型约束条件、以及表征游程域特征的方法;最后,基于游程域局部和全局特征,构建了长m序列动态电能参比测试信号模型,实验分析了游程域特征对电能表动态误差的影响,进而,提出了提升国际标准中电能表误差测试方法的建议。 展开更多
关键词 复杂电能信号 游程域特征 信号特征建模 多特征约束模型 电能表动态误差
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低信噪比条件下目标螺旋桨参数估计方法
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作者 韩闯 冷冰 +1 位作者 兰朝凤 邢博闻 《电子与信息学报》 北大核心 2025年第7期2149-2162,共14页
螺旋桨广泛应用于各类航空与航海设备中,如无人机、直升机以及水下舰船,尤其在水下目标探测中,目标的螺旋桨能提供丰富的特征信息。螺旋桨的微动产生的微多普勒频率能够反映其结构和动态行为,成为识别海洋目标的重要指标。准确识别水下... 螺旋桨广泛应用于各类航空与航海设备中,如无人机、直升机以及水下舰船,尤其在水下目标探测中,目标的螺旋桨能提供丰富的特征信息。螺旋桨的微动产生的微多普勒频率能够反映其结构和动态行为,成为识别海洋目标的重要指标。准确识别水下目标螺旋桨的参数,如桨叶数目、桨叶长度以及转速等,对于目标的身份识别具有重要意义。然而,水下探测环境复杂多变,杂波干扰成为常态,对微动特征精准提取构成了挑战,尤其是强杂波背景下,信号处理的难度显著增加。以水下目标螺旋桨参数识别为例,该文针对低信噪比条件下螺旋桨参数估计的挑战,提出一种基于复数域变分模态分解(CVMD)和正交匹配追踪(OMP)算法的新方法。首先分析了螺旋桨回波信号的复杂特性,探讨了传统方法在噪声环境下的局限性。随后,引入CVMD算法对信号进行分解和去噪处理,有效提高了信号的分离能力和抗噪声能力。通过时频分析获取目标闪烁参数,并将其作为先验信息对稀疏字典进行降维处理,降低正交匹配追踪算法的运算量,提高了微动特征参数的估计精度,利用OMP算法,精确提取了螺旋桨的微多普勒特征,实验结果验证了方法的有效性和稳定性。最后,比较了CVMD-OMP方法与传统方法在不同信噪比条件下的性能表现,展示了其在水下声学目标识别中的应用潜力和优势。 展开更多
关键词 微多普勒 信号去噪 特征提取 复数域变分模态分解 正交匹配追踪
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OTFS分阶段权重调控的MRC检测算法
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作者 党柯 孙锦华 吴小钧 《西安电子科技大学学报》 北大核心 2025年第3期61-72,共12页
正交时频空调制技术是近年来提出的一种新型信号调制方式,旨在解决高移动性多径传输场景下,由多普勒频移引起的通信质量下降问题。为了克服在传输过程中产生的符号块间干扰,采用补零填充正交时频空调制结构,重点分析了在时延-时间域重... 正交时频空调制技术是近年来提出的一种新型信号调制方式,旨在解决高移动性多径传输场景下,由多普勒频移引起的通信质量下降问题。为了克服在传输过程中产生的符号块间干扰,采用补零填充正交时频空调制结构,重点分析了在时延-时间域重调制加权输出的最大比合并检测算法中权重系数与迭代次数、信噪比以及调制阶数对系统收敛性与误码率性能的影响。针对高阶调制方式下因固定最佳权重系数导致迭代次数较高的问题,提出了一种基于分阶段权重系数调控的最大比合并检测算法,通过在不同迭代阶段合理设置权重系数,使每个迭代阶段的权重选择更加符合当前系统状态的需求,从而逐步优化现有最大比合并检测的过程,提升整体检测性能。实验结果表明,改进后的最大比合并检测算法显著加快了收敛速度,并在保持相同迭代次数的情况下,进一步改善了系统的误码率性能。此外,改进算法在多种信道条件下均表现出较强的适应性和鲁棒性,可以有效对抗高速移动场景下的快时变信道。 展开更多
关键词 正交时频空 最大比合并 低复杂度 信号检测
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城市动态场景GNSS信号特征及其对NLOS自主识别影响分析 被引量:1
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作者 别秭锟 王鑫宇 刘万科 《测绘地理信息》 2025年第2期83-88,共6页
在城市复杂环境中,GNSS信号易发生折射、衍射、遮挡等现象,产生严重的多路径效应和非视距(none line of sight,NLOS)误差;特别是NLOS信号可能会导致数十、上百米的伪距和载波相位误差,严重影响复杂环境下的GNSS定位精度和稳定性。本文... 在城市复杂环境中,GNSS信号易发生折射、衍射、遮挡等现象,产生严重的多路径效应和非视距(none line of sight,NLOS)误差;特别是NLOS信号可能会导致数十、上百米的伪距和载波相位误差,严重影响复杂环境下的GNSS定位精度和稳定性。本文重点分析了城市动态场景下GNSS NLOS信号在高度角、信噪比、伪距一致性、相位一致性、双差伪距残差和双差相位残差等6个方面的特征,并使用随机森林(random forests,RF)就信号特征对NLOS自主识别的影响加以初步分析。结果表明:80%以上的NLOS信号的高度角低于60度、信噪比低于45 dB-Hz;NLOS信号的伪距一致性和相位一致性会出现明显的离群现象,双差伪距残差和双差相位残差存在明显的大幅度波动。实时动态场景下的NLOS自主识别结果表明,高度角和信噪比对NLOS识别准确度的影响最大,伪距一致性和相位一致性次之;而双伪距残差和双差相位残差则是离线进行NLOS自主识别时的两个重要特征,仅使用高度角、信噪比、双差伪距残差、双差相位残差四个特征就能使基于随机森林的NLOS识别准确度达到80%左右。 展开更多
关键词 全球卫星导航系统 复杂场景 非视距信号 信号特征 随机森林
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