ID 原文 译文
23295 粒子群优化算法(PSO)是合成天线阵列预期方向图的有效手段。 Particle Swarm Optimization (PSO) is an efficient technology to synthesize desired pattern of antenna arrays.
23296 但对于某些大型平面阵列方向图复杂的非线性优化问题，该算法收敛速度慢且最优粒子易陷入局部最优解，因而使得算法失效。 But in some complicated cases, the optimizer will fail because the optimum particles fall into local best solutions and the convergence is so bad, especially for nonlinear optimization of large planar arrays pattern.
23297 针对这一问题，该文提出一种改进 PSO 算法来提高传统 PSO 算法的收敛特性。该算法在初始化最优粒子时采用解析初值而不是随机初值。 To solve this problem, a modified optimizer is presented to improve the convergence of traditional PSO by means of initializing the particles with analytical values rather than random values.
23298 对于给定的预期方向图，通过矩阵运算解析对应该方向图的阵元权系数。之后将这些权系数指定为任意一个粒子的解析初值，而种群的其他粒子仍然赋随机初值，之后再衔接标准 PSO 算法的寻优迭代过程。 For any given desired pattern, the corresponding aperture weights can be derived by matrix operations and these weights are then used as a particle's initial values while other particles are still initialized randomly.
23299 这种初始化方法使得种群粒子在寻优搜索过程开始之前，即可得到最优粒子初值的有效估计。 By this initialization, an efficient estimation of the optimum particle's initial values can be achieved before the beginning of all particles searching process.
23300 仿真结果表明，相对于全部粒子赋随机初值的标准算法而言，这种改进算法收敛速度更快，适应度值收敛得更深，因而有效提高了算法的收敛特性，从而能够得到满足预期方向图指标要求的优化结果。 The simulation results prove that this modified optimizer converges more rapidly and deeply than the traditional PSO and more satisfying global solutions and desired pattern could be obtained.
23301 双基星载高分辨率宽测绘带 SAR 系统(HRWS-SAR)利用数字波束形成技术(DBF)将俯仰向多通道的回波信号进行快时间域的相干合成，DBF 处理性能必然受到双基构型的影响。 In bistatic spaceborne High Resolution Wide Swath SAR (HRWS-SAR) system, the Digital Beam Forming (DBF) technique is employed to achieve the coherent combination of multi-channel signals in the fast time domain, and its performance is affected by the bistatic configuration.
23302 该文针对一般双基构型的星载 HRWS- SAR 系统，推导了点目标接收方向角与收发距离和之间的线性近似表达式，建立了俯仰向通道的回波信号模型，进而构建了一种时变加权与 FIR 滤波相结合的 DBF 处理方法，并给出了系统实现框图。 For a point target, the relationship between receiver aspect angle and the sum of transmitter distance and receiver distance is approximated by a linear function, and the echo signal model in elevation channel is built. Further, a DBF processing scheme is proposed, which combines the time-variant weighting and Finite Impulse Response (FIR) filtering, and the implementation block diagram is presented.
23303 该文对几种典型双基构型的星载 HRWS-SAR 系统 DBF 处理进行了仿真，结果表明合理的双基构型能有效提升星载 HRWS-SAR 系统的 DBF处理性能。 The DBF processing is simulated in several typical bistatic configuration spaceborne HRWS-SAR systems. Simulation results show that the higher DBF performance can be achieved in the spaceborne HRWS-SAR system with rational bistatic configuration.
23304 该文给出一类相互正交的二元零相关区序列集构造法。 A class of mutually orthogonal binary Zero Correlation Zone (ZCZ) sequence sets are constructed.