共查询到20条相似文献,搜索用时 156 毫秒
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给出了一种仅改变相位分布的阵列天线波束赋形优化算法.在不改变阵列天线各单元的馈电幅度分布的前提下,为了使天线的辐射波束形成给定的方向图形状,采用联合应用DFP和BFGS公式的变度量优化算法对阵列天线各单元的馈电相位分布进行优化,使得优化后的阵列天线主波束形状能够与预给的波束形状吻合,从而达到设计要求.该方法为N维函数无约束极小值方法,具有快速收敛、计算量小的优点,是一种阵列天线波束赋形的通用方法. 相似文献
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在相控阵天线的应用中,有时需要实现左右不同的副瓣电平。为了减少计算量,我们希望能使用尽量少的参数实现对副瓣不同要求的波束赋形。本文提供一种设计方法,针对一个16 单元的阵列,只对天线16 个单元的幅度以及其中一个单元的相位进行优化,其15 个单元的相位随扫描角度变化。通过差分进化算法的优化能迅速方便的得到所需
的幅度相位值,对各个扫描角度实现不同副瓣的波束赋形,使天线在左右的副瓣电平分别为-25 dB 和-35dB。 相似文献
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Madhab Dhali Avishek Chakraborty Gopi Ram Durbadal Mandal 《International Journal of Communication Systems》2023,36(4):e5401
This paper presents an optimization-based approach to compensate for the mutual coupling effect and to reduce the sidelobe level (SLL) of the normalized radiation pattern by optimizing the current excitation amplitude of the antenna array elements. Due to the mutual coupling effect, the SLL of the radiation pattern is increased, and thereby, the field pattern of the antenna array is severely degraded. This causes interference with other communication systems working at the same frequency. Toward the compensation of the mutual coupling effect and reduction of SLL, the Cat swarm optimization (CSO) algorithm is employed, and the excitation amplitudes of the antenna elements are optimized. In this regard, optimizing the cost function is defined by introducing the impedance factor (IF), calculated by using the self-impedance and mutual impedance of the antenna elements. The proposed method for the synthesis of a mutually coupled linear antenna array is less expensive, simpler to use, and more effective. Array sets of 4, 6, 8, and 10 elements are considered for optimization. 相似文献
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Reconfigurable antenna arrays are often capable of radiating multiple patterns by altering the excitation phases of the array elements. In this paper, an efficient method based on FFT is presented for generating dual-radiation pattern from a single rectangular planar array by modifying the excitation phases of the array elements while sharing common amplitudes. The common amplitudes shared by both the patterns and the phases which play the role of turning between the two patterns when updated over zero phase among the elements are computed using Self-adaptive Differential Evolution (SaDE) algorithm. Two different beam-pairs of pencil/pencil and pencil/flat-top are generated from the proposed array while maintaining precise design specifications. The proposed method greatly reduces the computational time as compared with the conventional method for calculating beam patterns. The dynamic range ratio of the excitation amplitudes are kept below a threshold level to reduce the design complexity of the attenuators at the feed network level and to minimize the effect of mutual coupling among the array elements. To illustrate the effectiveness of SaDE, the fitness functions associated with the two beam-pairs are minimized individually using differential evolution (DE) algorithm and particle swarm optimization (PSO) algorithm. Results clearly show the superiority of SaDE over DE and PSO to handle the proposed problem. 相似文献
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建立了优化非均匀线阵的数学模型,提出采用模拟退火算法优化非均匀线阵测向性能的新方法。该方法只需要一个入射方向准确已知的信号源来完成优化。优点是优化过程简单、稳定性较好,并且适用于任意形式的天线阵。大量的计算机模拟结果表明优化后阵列的测向性能有较大提高,从而验证了这种方法的有效性。 相似文献
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Antenna array optimization by a biquadratic programming method is formulated with variable-phase (analog and digital) and constant amplitude excitation. The method can optimize an antenna performance index expressible as a ratio of Hermitian quadratic forms. Power gain optimization and least-squares pattern synthesis with a specified gain are illustrated. Linear, planar, and circular arrays with dipole or circular loop elements are optimized, taking mutual coupling effects between antenna elements into account. The method shows much more rapid convergence characteristics than the Rosenbrock (1960) and Fletcher-Power (1963) methods 相似文献
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建立了一种通用的适应度函数式,通过遗传算法对八元阵优化,逼近二项式分布和切比雪夫分布,验证了算法的正确性。通过对八元阵方向图不同目标的优化,说明该算法及适应度函数的设计对任意布阵天线方向图多目标优化的有效性。 相似文献