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提出了一种基于时频分布迭代的跳频信号参数估计新算法,利用时频平面最大值,通过计算跳频信号与最优原子时频分布的残差逐次迭代获取匹配于跳频信号分量的时频参数,进而实现跳频信号参数估计.理论分析和仿真结果表明,与基于匹配追踪和粒子群优化的跳频信号参数估计相比,基于时频分布迭代的参数估计算法在保证算法精度的情况下,有效地降低了算法的计算复杂度,为跳频信号盲接收的实时实现提供了一种新方法. 相似文献
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二次时频表示中核函数的优化设计 总被引:1,自引:1,他引:0
二次时频分布是分析非平稳信号的有力工具,在具有许多优良特性的同时,存在严重的交叉干扰项。在Wigner-Ville分布及Cohen类时频分布具有固定核函数的基础上,研究了基于信号的核函数优化设计的两种方法,径向高斯核函数和最优相位核函数的设计方法。基于信号的核函数的时频表示可以有效地抑制或转移交叉分量,提高时频表示的可读估计,改善其主要性能。 相似文献
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综合采用直接序列扩频(DSSS)和跳频扩频(FHSS)体制的直序/跳频(DS/FH)通信信号显著降低了单位时频面积上的功率,经典的时频-多信号分类(TF-MUSIC)算法对这一类信号进行入射角(DOA)估计时误差较大。为解决该问题,本文对TF-MUSIC算法进行改进,在时频二维平面上计算DS/FH信号的时频特征值,并设计相应的时频掩膜滤波核函数,再根据估计出来的循环平稳频率计算相应的循环平稳空间自相关矩阵,得到了循环平稳可变核函数TF-MUSIC(CVCFTF-MUSIC)算法。该算法可显著提高DOA估计的精确度,数值仿真验证了上述观点。 相似文献
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The cone-shaped kernel generalized time-frequency representation (GTFR) of Zhao, Atlas, and Marks (ZAM) has been shown empirically to generate quite good time frequency representation in comparison to other approaches. The authors analyze some specific properties of this GTFR and compare them to other TFRs. Asymptotically, the GTFR is shown to produce results identical to that of the spectrogram for stationary signals. Interference terms normally present in many GTFRs are shown to be attenuated drastically by the use of the ZAM-GTFR. The ability of the ZAM-GTFR to track frequency hopping is shown to be close to that of the Wigner distribution. When a signal is subjected to white noise, the ZAM-GTFR produces an unbiased estimate of the ZAM-GTFR of the signal without noise. In many other GTFRs, the power spectral density of the noise is superimposed on the GTFR of the signal. It is also shown that, in discrete form, the ZAM-GTFR is generally invertible 相似文献
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本文提出了一种实现合成孔径雷达(SAR)成像处理的并行距离/多普勒算法,该算法能有效地提高SAR的成像处理速度,是实现SAR实时成像处理的有效途径,该算法尤其适合于超级并行机(MPP)及工作站和微机构成的群机系统进行并行计算。实验结果表明该并行算法能有效地减少SAR成像处理的运算时间。最后给出了原始数据的成像结果。 相似文献
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Chung-Chin Lu Jau-Yuan Hsu Chih-Chung Cheng 《Communications, IEEE Transactions on》2005,53(10):1718-1728
This paper presents the systolic array implementation of a real-time symbol-optimum multiuser detection (MUD) algorithm for a direct-sequence code-division multiple-access system by truncating the backward recursions in the generalized forward/backward schedule. Simulation results show that the real-time algorithm provides negligible performance loss compared to the original symbol-optimum detection algorithm. The systolic array implementation is derived in this paper through the factor graph language of the real-time algorithm in order to exploit the suitability of the algorithm for parallel signal processing. 相似文献
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动态时间规整算法DTW(Dynamic Time Warping)作为一种非线性时间匹配技术已成功地应用于语音识别系统中。DTW算法使用动态规划技术来搜索两个时间序列的最优规整路径,虽然这种算法计算量小,运算时间较短,但只是一种局部优化算法。禁止搜索TS(Tabu Search)算法是一种具有短期记忆的广义启发式全局搜索技术,适用于解决许多非线性优化问题。本文将该技术用于语音识别系统中,提出了基于禁止搜索的非线性时间规整的优化算法TSTW,使得时间规整函数尽可能逼近全局最优。仿真结果表明,TSTW比DTW有更高的识别率,且运行时间比遗传时间规整算法GTW大大减少。 相似文献
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研究了时延估计算法在超宽带(Ultra Wide Band)定位中的应用,其广义相关自适应时间延迟估计算法的收敛速度慢,在低信噪比条件下时间延迟估计精度较低。针对低信噪比条件下的收敛特性,提出一种最大似然加权的广义相关自适应时间延迟估计算法,并进一步提出了改进的基于最大似然(Maximum Likelihood)加权函数的广义互相关时延估计算法。改进的算法采用加窗法和自适应时变干扰删除滤波法,弥补了原算法计算量大及无法消除时变信号干扰的不足。仿真结果表明,改进的算法计算复杂度明显降低,能够有效地消除其他信号干扰,具有较高的时延估计精度和鲁棒性。 相似文献
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为了克服目前GPS (Generalized Processor Sharing)类调度算法中实时应用分组的排队时延较大且不稳定的局限性,该文提出一种新的分组排队调度算法,该调度算法在计算分组服务标签时添加了一个紧急程度函数,调整了到达分组间的竞争关系,从而可以按照实时性应用的要求来调整到达分组的转发先优级,由此显著降低了实时性应用分组的排队时延和抖动幅度。分析和仿真实验表明,与GPS类其它调度算法相比,该调度算法对于实时应用的分组能提供较低的、更稳定的排队时延保证,同时还继承了GPS类算法的公平性和排队时延有界等特性,而且对系统虚拟时间的跟踪计算更为简捷高效。 相似文献
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Vincent T.L. Khargonekar P.P. Terry F.L. Jr 《Semiconductor Manufacturing, IEEE Transactions on》1997,10(1):42-51
In this paper a new algorithm is presented for determining etch rate from single or multiple wavelength reflectometry data. This algorithm is based on techniques from recursive nonlinear estimation theory-Extended Kalman Filtering. A major advantage of our algorithm is extremely high speed, with computation time less than 1 ms on a Pentium PC. Consequently, it can be used in real-time feedback control applications. The speed advantage also makes it a suitable candidate for full wafer (or multi-point) high-speed etch rate measurement 相似文献
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N. P. Karampetakis 《Circuits, Systems, and Signal Processing》1997,16(4):439-453
The main contribution of this paper is to present (a) an algorithm for the computation of the generalized inverse of a not necessarily square two-variable polynomial matrix and (b) some applications of the proposed algorithm to the solution of Diophantine equations.This work is supported by the Greek General Secretariat of Industry, Research and Technology. 相似文献
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An optimised algorithm for real-time implementation of the discrete Wigner distribution (DWD) is presented. The algorithm makes use of the symmetry properties in the Wigner kernel and computes the analytic signal recursively in the time domain. Its computation complexity is found to be very small compared with the direct implementation of the DWD when real-time processing is needed.<> 相似文献