共查询到18条相似文献,搜索用时 140 毫秒
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校正源信号方向角不容易精确测量,限制了阵列有源校正方法的精度。另一方面,无源校正方法难以应用于存在大阵列误差的场合,其实际应用也受到严重限制。该文提出一种基于旋转测量的阵列幅相误差校正新方法,无需测量校正源信号方向角就能获得较高的校正精度。该方法利用已知的阵列旋转角度,基于最大似然准则获得阵列幅相误差、校正源信号方向角及其复振幅的无模糊估计。相对于校正源信号方向角,阵列旋转角度通过专用测试转台更容易精确测量,因此该方法能以较小的代价获得很高的校正精度。仿真实验验证了该方法的有效性和通用性。 相似文献
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根据子空间的基本原理,提出一种新的阵列天线幅相误差校正算法,该方法利用粗略已知的校正源方位角信息进行优化,使用迭代的方法逼近幅相误差的真实值.由于不需要其他的迭代初始值,从而保证该方法能收敛到最优解.计算机仿真实验证明了该方法的有效性. 相似文献
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宽带数字阵列雷达通道中特性差异,使得通道产生随频率变化的幅相不一致性,文中主要研究了时域和频域的校正算法,并根据不同频点的对角因子形成相应的对角加权矩阵,改进了加权最小二乘拟合的方法,优化了频域算法,最后通过仿真对比分析了时域与频域算法的精度和对数字波束形成性能的影响,并验证了改进频域算法的精确性与可行性。 相似文献
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在大型数字相控阵系统中,为了满足阵列增益及天线方向图特性,需要保证阵列通道的幅度和相位的一致性,而动态不一致性标校是大型阵列的标校难题。提出了一种基于直接数字频率合成(Direct Digital Synthesizer,DDS)相位搜索算法的数字相控阵通道一致性标校技术,较传统基于相关算法的标校技术,可有效降低对标校信号信噪比的要求,且可提升大规模数字阵列通道标校的效率。仿真结果表明,当信噪比等于0 dB时,采用所提算法可将幅度估计误差的均方根误差(Root Mean Square Error,RMSE)值控制在0.3 dB以内,相位估计误差的RMSE值可控制在1.5°以内,较传统算法的性能均提升了3倍。通过搭建样机评估系统,进一步验证了提出算法对数字相控阵通道一致性标校性能的提升。 相似文献
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Array calibration in the presence of multipath 总被引:7,自引:0,他引:7
We present an algorithm for the calibration of sensor arrays in the presence of multipath. The algorithm is based on two sets of calibration data obtained from two angularly separated transmitting points. We show the similarity between the calibration problem and blind identification of SIMO systems and analyze the identifiability of the problem. Simulation results demonstrating the performance of the algorithm are included 相似文献
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For the mobile communication satellite each beam communication traffic distribution was not balanced,leading to differences in transmission power of downlink beam.The implementation architectures of dynamic power allocation network was given,which could allocate the transmitting beam power automatically according to the traffic demand,at the same time ensured the high efficiency of power amplifier.Because the performance of dynamic power allocation network was severely impaired by the mutual coupling among signals when amplitude/phase mismatch was existed,which led to a sharp drop in beam performance.A calibration method for the amplitude and phase errors was proposed.The decoupling of calibration signal was realized by using the cross-correlation orthogonal characteristic of the orthogonal zero-correlation zone (ZCZ) sequences in the zero correlation interval,and communication was free from calibration by reducing the transmit power for the excellent self-correlation characteristic of the ZCZ sequences.Performance simulation and far field test show that under the condition that the calibration signal power is less than the normal signal 10 dB,the amplitude error is less than 0.1 dB,the phase error is less than 0.3°,and the gain loss within the main lobe is less than 0.2 dB after calibration. 相似文献
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