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1.
一种脉冲多普勒雷达解模糊新算法   总被引:15,自引:0,他引:15       下载免费PDF全文
曾涛  龙腾 《电子学报》2000,28(12):99-101
模糊问题是脉冲多普勒雷达的固有问题.目前常用的解模糊算法是孙子定理方法和一维集算法.本文提出了一种新的解模糊算法,即群算法.这种算法对测量误差不敏感,而且既可以解距离模糊又可以解多普勒模糊,所以它的性能优于孙子定理算法.另一方面,由于使用了查找表,群算法的计算量比一维集算法小,因而更适合实时处理.  相似文献   

2.
脉冲多普勒雷达在目标检测时常常存在距离模糊问题,目前比较成熟的解距离模糊算法有一维集算法和余差查表算法。在一维集算法的基础上,提出了一种改进的脉冲多普勒雷达解距离模糊新算法。该方法具有运算速度快、实时性能好的特点。通过对四目标距离模糊解算仿真和实际应用结果表明,该算法与一维算法相比运算时间减少了48%,验证了其高效性和有效性。  相似文献   

3.
脉冲多普勒雷达中的解模糊算法及实现   总被引:8,自引:1,他引:7  
解距离模糊和解速度模糊是中重复频率脉冲多普勒雷达中需要解决的重要问题.其算法的依据都是中国余数定理。但是.单靠中国余数定理仍无法解决距离测量和多普勒频率测量中的误差和遮挡问题。本文讨论了在测量误差和遮挡问题存在的情况下解距离模糊所采用的建表搜索法和解速度模糊所采用的各模糊度内最小方差过门限法.并将这两种算法与其他算法进行了对比。文中所提算法具有重要的工程应用价值。  相似文献   

4.
脉冲多普勒雷达在中重频下存在距离模糊、速度模糊问题,传统算法先解距离模糊再解速度模糊。在复杂电磁环境(存在杂波、干扰)下,上述算法存在如何选择距离门配对解模糊的难题。本文针对这种情况提出一种新算法,在距离维和速度维联合解模糊,并通过仿真验证了算法的有效性。  相似文献   

5.
一种脉冲多普勒雷达解距离模糊的新算法   总被引:2,自引:0,他引:2  
脉冲多普勒雷达在信号检测时存在距离模糊和速度模糊的问题,为了解决模糊问题,在体制上雷达一般采用多重脉冲重复频率(PRF)的工作方式。对于这种体制的雷达,人们已经给出了多种解模糊算法。本文主要阐述了一种解距离模糊的新方法及其实现步骤,并给出了利用该算法解距离模糊的仿真结果。  相似文献   

6.
一种高脉冲重复频率雷达微弱目标检测跟踪方法   总被引:4,自引:0,他引:4  
针对高脉冲重复频率(PRF)雷达对微弱目标的检测跟踪问题,该文提出一种雷达测距模糊条件下基于检测前跟踪(TBD)的微弱目标跟踪方法.该算法借用TBD的思想精髓,对于每一时刻的量测,既不进行目标有无的检测也不解距离模糊,而是将目标检测和解距离模糊统一在目标真实航迹的获取中.首先通过批处理把目标的模糊量测在所有模糊区间进行多假设扩展,从而提取量测的时空相关信息;然后基于目标真实航迹在时空上的连续性和不同PRF量测之间的相关性,通过TBD方法得到目标航迹,同时实现解距离模糊.与同类研究相比,该方法将微弱目标解距离模糊问题统一到目标航迹的检测确认过程中,避免了低信噪比(SNR)造成的航迹漏检,为实现高脉冲重复频率雷达微弱目标的检测跟踪提供了一种新的思路.最后,通过仿真验证了该算法的有效性.  相似文献   

7.
地面MPRF-PD雷达工作于中重频下,同时存在距离、速度模糊,雷达通常都会采用参差重频的工作方式进行解模糊,传统的解模糊方法本质为二进制积累,会带来信噪比损失,不利于小目标的检测.鉴于此,本文提出一种基于相参积累的地面MPRF-PD雷达二维联合解模糊算法,能够充分利用雷达脉冲资源,提高信噪比,可以同时有效实现小目标的检...  相似文献   

8.
一种PD雷达解距离模糊的新算法   总被引:3,自引:0,他引:3  
针对PD雷达的解距离模糊问题,文中分析指出一维集算法解模糊计算量大,有时难以适应实时测距的要求.基于此点,在一维集算法基础之上提出了一种新的解模糊方法,通过理论分析证明了这种方法的计算量明显小于一维集算法,而且具有良好的误差纠错能力,并将这种新算法同余差查表法的各项性能进行了对比,体现了其同样具有较好的实时性能和较强的解模糊能力.最后给出利用这种算法解单目标距离模糊的仿真结果,表明了这种方法的有效性.  相似文献   

9.
距离—速度噪扰模糊数据同时分辨的孙子定理算法   总被引:5,自引:0,他引:5  
黄振兴  万征 《电子学报》1992,20(9):27-33
本文描述了一种推广的孙子定理,针对噪扰模糊数据发展了一种基于该定理的模糊分辨算法。该法可以同时完成中重复频率脉冲多普勒雷达的距离及速度的模糊分辨.文中还分析了该算法的正确解模糊条件及概率.  相似文献   

10.
张弢  陈铠  章晗 《现代雷达》2007,29(12):40-43
介绍了脉冲多普勒天气雷达解速度模糊和消距离模糊的原理,给出了几种常用解模糊方法的具体算法及其仿真结果,并对不同处理方法的性能进行了比较。描述了在某x波段车载脉冲多普勒天气雷达以通用DSP芯片TMS320C6701为核心的信号处理系统中,采用双脉冲重复频率解模糊的具体实现方法,最后给出了解速度模糊和消距离模糊的实际效果图。  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

17.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

18.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

19.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

20.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

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