| 摘要: |
| 针对频率分集阵列（Frequency Diverse Array，FDA）方向图中固有的距离 角度耦合给波束控制带来的问题，本文通过遗传算法解算FDA阵列的非线性 时变频偏。首先，通过采用非线性频控函数实现FDA方向图解耦。在此基础上，将现有文献中线性增量 时变频偏表达式推广为适用于倒数等非线性频控函数的形式。之后，针对无法得到固定时变频偏表达式的log FDA及sin FDA阵列，应用遗传算法通过凸优化求解，同时在约束条件中添加脉冲持续时间约束，从而得到主瓣增强旁瓣抑制的FDA非时变解耦方向图，在脉冲周期内形成固定的波束指向，有效改善因目标照射时间不足导致回波能量低的问题。最后，仿真验证了本文结论的正确性。 |
| 关键词: 频率分集阵列 解耦 非线性增量 时变频偏 遗传算法 |
| DOI：DOI:10.3969/j.issn.1672-2337.2020.01.015 |
| 分类号:TN95 |
| 基金项目:国家自然科学基金青年基金项目（No.61503408） |
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| Decoupling of Frequency Diverse Array Time Invariant Beam Pattern Based on Genetic Algorithm |
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WANG Bo，XIE Junwei，ZHANG Jing，SUN Bosen
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1. Air and Missile Defense College，Air Force Engineering University，Xi’an 710051，China;2.2. Shannxi College of Communication Technology，Xi’an 710018，China;3. Xi’an University of Finance and Economics，Xi’an 710100，China
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| Abstract: |
| Considering the problems caused by the range angle coupling inherent in the frequency divers array (FDA) beampattern，this paper solves the nonlinear incremental time dependent frequency offset of the FDA array by genetic algorithm. First，the decoupling of the beampattern is achieved by using a nonlinear frequency offset increment between the array elements. On this basis，the linear incremental time dependent frequency offset proposed in the existing literatures is generalized to the form suitable for nonlinear frequency offset such as reciprocal.Then，for the log FDA and sin FDA that cannot obtain fixed time dependent frequency offset expressions，the genetic algorithm is applied to solve the convex optimization problem. And the pulse duration constraint is added in order to obtain the time invariant decoupling beampattern with mainlobe enhanced and sidelobe suppressed. The time invariant decoupling beampattern forms a fixed mainlobe pointing during the pulse period，which effectively mitigates the problem of low echo energy due to insufficient target illumination time. Finally，the simulation verifies the validity of the results. |
| Key words: frequency diverse array decoupling nonlinear incremental time dependent frequency offset genetic algorithm |
