共查询到20条相似文献,搜索用时 15 毫秒
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二阶锥规划作为凸优化理论的一个分支,近些年来已应用于波束形成的研究,但在已有研究中基于均匀线阵的一维波束形成研究得较多,且较少考虑不同指向下的束宽恒定问题。因此,基于矩形平面阵,将二阶锥规划的一维束宽恒定波束形成方法扩展到二维作为主要研究目标,首先采用Dolph-Chebyshev加权方法设计出二维参考波束,再以主瓣逼近和旁瓣最小为约束,引入二阶锥规划方法设计了支持不同俯仰角和方位角指向的二维波束。经仿真分析,所提方法可实现在三维空间中的不同指向下的波束形成,且在俯仰角设定后,在不同方位指向下可实现3 dB束宽较恒定的波束,减少了指向对波束特性的影响,方便于应用。 相似文献
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随着网络功能虚拟化(NFV)技术的发展,虚拟网络功能(VNF)可以通过服务功能链(SFC)的形式部署在如虚拟机的通用平台中,为管理带来灵活性。但是对于服务提供商来说,由于网络基础设施的复杂性和日益增长的服务需求,给VNF的部署带来了高昂的运营成本(OPEX)。针对此问题,该文提出一种面向OPEX优化的策略,旨在最小化OPEX中的激活、能耗和传输成本,得到VNF部署和路由分配优化方案。为此建立一种全新的混合整数线性规划(MILP)模型,并设计包括遗传算法(GA)在内的3种OPEX优化算法。仿真实验评估在不同资源配给下MILP和3种算法的OPEX及其性能,其中GA算法在节点资源配比60%以上时可以得到近似于MILP模型的解决方案。 相似文献
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The present paper provides an efficient approach to multiple criteria redundancy optimization problems, often encountered in reliability design of engineering systems. A search technique introduced earlier [10,11] in combination with the multicriteria optimization methods, based on min-max concept for finding Pareto optimal solution of multicriteria optimization problems, provides an efficient and excellent approach for solving redundancy optimization problems. The approach is illustrated through several numerical examples. Further, based on this approach, a very general computer code called ESMOP (Efficient Search Multi-Objective Programming) has also been developed. It is capable of considering any type of redundancy, constraint or individual cost function and thus offers to solve many reliability design problems. 相似文献
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Wenxuan Guo Xinming Huang Wenjing Lou Cao Liang 《Mobile Networks and Applications》2008,13(1-2):186-197
Wireless networks that operate on batteries are imposed with energy constraints and long distance communications between nodes are not desirable. Implementing Relay Nodes (RNs) can improve network capacity and save communication energy. A two-hop relay routing scheme is considered, in which the RNs are temporarily placed and have energy constraints. This paper investigates a joint optimization problem on Relay Node Placement (RNP) and route assignment for two-tiered wireless networks. A recursive Weighted Clustering Binary Integer Programming (WCBIP) algorithm is proposed to maximize the total number of information packets received at the Base Station (BS) during the network lifetime. We first present an optimization algorithm based on Binary Integer Programming (BIP) for Relay Node Assignment (RNA) with the current node locations. Subsequently, a weighted clustering algorithm is applied to move the RNs to the best locations to best serve their respectively associated Edge Nodes (ENs). The algorithm has the complexity of O(2 n ). The simulation results show that the proposed algorithm has significantly better performance than the other two relay placement schemes. Both theoretical analysis and practical design procedures are also presented with details. 相似文献
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该文提出了基于2阶锥约束(SOCP)的方向不变恒定束宽波束形成算法。本算法的优化准则为在保证各个指向上设计波束的主瓣与相应的参考波束的主瓣之间的均方误差最小的条件下,使设计波束旁瓣级尽量低。该约束优化可转化为标准2阶锥形式,采用优化工具箱SeDuMi实现。仿真计算表明,新算法能够在主波束指向60范围内得到良好的方向不变恒定束宽波束图。 相似文献
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YuanWeiming WangMin WuShunjun 《电子科学学刊(英文版)》2005,22(2):185-189
A novel algorithm based on Radon-Ambiguity Transform (RAT) and Adaptive Signal Decomposition (ASD) is presented for the detection and parameter estimation of multicomponent Linear Frequency Modulated (LFM) signals. The key problem lies in the chirplet estimation.Genetic algorithm is employed to search for the optimization parameter of chirplet. High estimation accuracy can be obtained even at low Signal-to-Noise Ratio(SNR). Finally simulation results are provided to demonstrate the performance of the proposed algorithm. 相似文献
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针对目标识别的波形优化设计方法 总被引:3,自引:0,他引:3
针对宽带雷达多类目标识别波形优化中的方位敏感性、距离敏感性和初相不确定性问题,该文在高斯色噪声背景下提出一种基于遗传算法和最大滑动相关分类器的波形优化方法,简称为GASC方法。该方法定义目标回波和同类模板之间的匹配系数与该目标回波和异类模板之间匹配系数的差为匹配距离,以最大化各类目标之间的匹配距离的最小值作为优化准则,并约束发射信号幅度是恒定的,然后通过遗传算法进行求解,得到优化波形信号。仿真结果表明,与现有方法相比,该方法能更好地增加各类目标之间的可分性,进而提高目标的识别性能。 相似文献
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The problem of recovering sparse signals and sparse gradient signals from a small collection of linear measurements is one that arises naturally in many scientific fields. The recently developed Compressed Sensing Framework states that such problems can be solved by searching for the signal of minimum L 1-norm, or minimum Total Variation, that satisfies the given acquisition constraints. While L 1 optimization algorithms, based on Linear Programming techniques, are highly effective at generating excellent signal reconstructions, their complexity is still too high and renders them impractical for many real applications. In this paper, we propose a novel approach to solve the L 1 optimization problems, based on the use of suitable nonlinear filters widely applied for signal and image denoising. The corresponding algorithm has two main advantages: low computational cost and reconstruction capabilities similar to those of Linear Programming optimization methods. We illustrate the effectiveness of the proposed approach with many numerical examples and comparisons. 相似文献
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遗传规划(Genetic Programming,GP)属于进化计算(Evolutionary Computation,EC)模型之一,同时具备全局寻优和个体表示自然的特点。此外,由于模糊理论更适合于模仿人类的思维推理。利用GP灵活的个体表示和对属性的模糊描述得到自然描述的规则,使规则易于理解,利用GP全局寻优的能力得到较好的入侵检测规则。最后给出了实验结果,并与其他文献的同类实验结果进行了比较,证明了改进GP的有效性和先进性。 相似文献
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量子遗传算法是一种融合量子计算和遗传算法优点的智能算法,常用于求解组合优化问题.本文给出多输出RM(Reed Muller)逻辑电路最佳极性搜索方案,将量子遗传算法应用到多输出固定极性RM电路逻辑优化中.针对量子遗传算法易陷入局部极值的缺陷,结合群体灾变思想,提出一种基于量子遗传算法的多输出RM逻辑电路最佳极性搜索算法.最后对多个大规模PLA格式基准电路测试表明:该算法与基于遗传算法的最佳极性搜索相比,在优化能力、寻优性能和收敛速度等方面都有不同程度的提高. 相似文献