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针对欺骗式干扰影响飞行器卫星导航信号后引起的定位测姿错误问题,提出了一种适用于飞行器导航的基于阵列天线的欺骗式干扰检测和消除方法.使用接收阵列天线的载波相位双差测量值作为干扰检测依据,通过载波相位单差测量方程求出干扰信号的方向矢量,给出了提高干扰方向测量精度的方法,并使用其正交向量在干扰方向形成零陷,同时通过调整波束指向,在待测信号方向形成阵列增益,以达到抗干扰和增强导航信号的目的.使用这种方法可以对导航信号中的欺骗式干扰信号进行有效的识别和消除,适用于复杂环境下的飞行器导航. 相似文献
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在阵列天线的应用中,需要控制阵列天线的方向图达到合适的副瓣电平要求。本文在对已有的一维阵列方向图综合算法进行研究的基础上,给出了一种基于自适应阵列信号处理理论的二维阵列天线方向图的综合算法,将待综合阵列假想为自适应阵列,通过不断调节对阵列施加的干扰,再由自适应算法调节阵列权值,最终得到合适的方向图。 相似文献
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基于非均匀延时阵列的同时多波束干扰技术研究 总被引:1,自引:0,他引:1
为解决现有文献中波束形成方法普遍存在的算法效率低、效果差、难以形成同时多波束干扰,和某些方法不适用于非均匀阵列等缺点,提出了一种基于非均匀延时阵列的同时多波束干扰设计方法.首先,给出了L2范数准则条件下干扰多波束优化设计问题的数学描述,并将其解析形式转化为相应的二阶锥规划形式;其次,给出了一种非均匀延时阵列的设置规则,按照此规则对传统模型中均匀阵列的阵元间距和单位延时进行改进设置;再次,利用现有的原-对偶内点算法工具箱SeDuMi或CVX进行快速有效求解.最后,仿真结果表明,该方法不仅可以较好地解决相应约束条件下,不同频率、不同方向的多个雷达目标的同时多波束干扰优化设计问题,而且其设计结果整体优于均匀阵列下的设计结果. 相似文献
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提出了一种基于阵列天线的卫星导航欺骗干扰检测与抑制方法。利用真实卫星导航信号从上半球空间多个方向入射到阵列天线而欺骗干扰信号则是从同一方向入射到阵列天线的差异性进行干扰检测判决。首先,对阵列天线每个阵元单元通道接收信号进行多颗卫星并行解扩从处理;其次,利用解扩后的阵列数据对每颗卫星进行方位估计;再次,根据估计卫星来向数据的一致性进行干扰检测判决;最后,在判决存在欺骗干扰时利用欺骗干扰的方向信息重构协方差矩阵,采用自适应调零算法对欺骗干扰进行抑制。通过计算机仿真试验对所提方法的正确性和有效性进行了验证。 相似文献
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基于去耦分析的圆形天线阵列方向图综合 总被引:13,自引:1,他引:12
本文在本征激励方向图分析方法的基础上提出本征激励方向图的去耦分析方法,该方法将包含互耦的圆形阵列方向图综合问题转化为我互耦的圆形阵列方向图综合问题,从而将传统的不考虑互耦的理想圆形阵列方向图综合方法与考虑互耦的本征激励分析方法结合起来,作为对该方法的验证,本文比照已有文献中的结构进行了计算,给出了计算结果进行了讨论。 相似文献
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When shaped beams are synthesized using array antennas with a limited number of elements, insufficient degrees of freedom sometimes result in practically unsatisfactory patterns. In such cases, it is very convenient if the unsatisfactory patterns can be improved to satisfactory ones using some techniques. An example is presented of such pattern improvement techniques. First, an algorithm necessary for the improvement technique is derived by modifying an algorithm commonly used for adaptive array antennas into a form not requiring real time information of receiving signals. Then, three application examples of this technique are presented. In the example of a shaped beam array antenna of which two elements are removed out of ten elements, measured results are compared to the calculated pattern to show the validity and usefulness of this technique. 相似文献
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给出一种基于反离散傅里叶变换阵列天线赋形波束的综合算法,综合后的阵列天线波束形状与预给的波束形状吻合较好,从而达到设计要求。该方法具有计算速度快、计算量小、计算数值稳定性好的优点。是一种阵列天线波束赋形的实用方法。 相似文献
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该文提出了一种虚拟的最小均方有源单元方向图展开方法,将不等间隔阵列的有源方向图展开为一个虚拟的均匀间隔阵列的若干单元辐射的叠加。通过该方法,对包含阵元耦合效应的不等间隔阵列方向图,可以使用快速傅里叶变换进行加速计算。并且,该文将这个方法与遗传算法(GA)相结合,得到一种改进的GA-FFT方法,可以应用于解决含阵元互耦的不均匀间隔阵列的赋形波束综合问题。最后,分别对不等间隔的偶极子阵列平顶方向图及微带阵列的余割平方方向图进行了综合,结果表明所提方法的有效性和优势。 相似文献
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详细介绍了一个具有双波束同步扫描功能相控阵天线的工作原理、设计方法及其实测结果,该天线为平面相控阵形式,工作频率为150~260 MHz,水平极化,增益大于28 dBi,同时具有方位低副瓣和俯仰余割赋形的特点。 相似文献
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The design and development of a Ku-band linearly polarized 16×16 microstrip-patch array is presented. The array is fed by a corporate network, using dog-bone shaped coupling apertures. Thin substrates and low-loss foam are used for antenna-bandwidth enhancement. The design of the radiating patches and feed network was aided by the commercial software package, Ensemble(R). Experimental results for the array, in terms of its return loss, radiation pattern, and gain, are presented 相似文献
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Kumar S.J. Chakraborty A. Das B.N. 《Antennas and Propagation, IEEE Transactions on》1991,39(6):851-854
A method of scanning a one-dimensional shaped pattern generated by a tilted circular planar array of nonisotropic elements is presented. A method of synthesis of phase function for a desired cosecant pattern and specified amplitude distribution for excitation of the elements of the array is presented. The phase distribution required in the perpendicular direction for retaining the beam shape in the scanned plane is determined. Computed results on the phase distribution and radiation pattern are presented. The appropriate correction is applied to get a better agreement between the realized and desired patterns in this scanned position of the beam 相似文献
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Shaped patterns can be produced by properly excited equispaced linear arrays. An earlier synthesis procedure, which accomplishes this with control ripple in the shaped region and controlled sidelobe levels elsewhere, results in array distributions that are generally complex. It is shown here that if the shaped pattern is symmetric and has 2M filled nulls, there are 2M complex symmetric distributions, and 2M pure real asymmetric distributions, and 22M-2M+1 complex asymmetric distributions that will produce the desired pattern. By adding 2M elements to the array, one can find a symmetric pure real distribution that will achieve the same result. A representative example illustrates the procedure. The results have application to standing-wave-fed planar arrays with quadrantal symmetry via use of the collapsed distribution principle 相似文献
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Basic array theory 总被引:10,自引:0,他引:10
Kummer W.H. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1992,80(1):127-140
Basic antenna array theory is outlined with major emphasis on pattern analysis and synthesis for periodic linear and planar arrays, phased arrays, and conformal arrays. Extension is made to synthesis techniques which use computer algorithms. These include arbitrary sidelobe control, shaped beams, and phase-only null steering. The subjects of random errors and phased array quantization errors are outlined 相似文献