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911.
论文简单概述了Xilinx现场可编程门阵列(FPGA)动态局部重配置的技术特点以及在现代软件无线电(SDR)中的应用.并以一个工程示例着重介绍了在某波形处理模块上采用飞思卡尔处理与FPGA内部微处理器配合的方案对FPGA进行局部功能动态配置的工程实现. 相似文献
912.
联合火力打击方案评估是对联合作战备选方案的综合评估,武器装备运用合理性作为方案的核心,关系着打击行动的费效比和作战企图能否实现。由于各种评估指标的不确定性,在评估中难免会出现不客观,缺乏科学合理性。文中基于BP神经网络建立评估模型,通过用MATLAB软件的仿真检验,证明了BP神经网络可以很好的对方案评估,避免人为因素的影响,可以科学,客观地对方案进行评估。 相似文献
913.
采用遗传算法的多机自由飞行冲突解脱策略 总被引:1,自引:0,他引:1
为了解决自由飞行时飞机间的冲突解脱问题,提出了一种能够快速准确解算最优航路的算法.遗传算法具有简单通用、鲁棒性强等特点,应用遗传算法通过改变飞行航向和飞行速度2种方式解决了两机及多机间自由飞行冲突解脱问题,同时还探讨了多机相对飞行时冲突解脱的有效飞行机制.仿真结果表明,无论是改变飞行航向还是改变飞行速度,算法均能够较快地得出最优冲突解脱路线,同时当多机在一点处存在冲突时,采用改变航向的解脱方式具有更好的适用性. 相似文献
914.
提出一种统一的呼叫接纳控制方法。应用层次分析过程(AHP)实现系统建模,根据网络运营目标,对于决策所依据的诸多准则之间的重要性关系进行定性分析和定量描述,从而确定各准则在决策中的影响力;应用中介真值程度度量(MMTD)方法统一量化各影响因素相对各准则的真值程度,通过配置合理参数,来适应异构网络在技术特性、性能目标上的差异。仿真结果表明,文中所提方法对于网络的运营目标和偏好具有很好的适应能力。 相似文献
915.
916.
为了解决传统的专用仪器开发难度大、周期长、成本高的问题,提出并实现了采用虚拟仪器技术实现的任意信号发生器,不但降低了开发成本,节省了开发时间,并且可以和其他虚拟仪器构成一个完整的实验系统而无需添加其他硬件产生信号输出供其他仪器使用.主要利用LabVIEW编程,在计算机内产生信号的数据,通过D/A模块将产生的数据按照一定的速率输出,从而得到连续的模拟信号波形.用户可以通过此虚拟任意信号发生器自己编辑波形,从而在真正意义上实现任意波形发生器功能. 相似文献
917.
This paper presents a joint relay selection and power allocation scheme for amplify-and-forward two-path relaying networks,in which diferent relay nodes forward information symbols alternatively in adjacent time slots.Our approach is based on the maximization of the received signal-to-noise ratio under total power consumption by the transmission of the symbol.We show that in spite of inter-relay interferences,the maximization problem has a closed-form solution.Simulation results explicitly indicate that the performance of proposed approach outmatches the existing methods including equal power allocation and one-path relaying. 相似文献
918.
Light detecting and ranging(LiDAR)technology has become an efective way to generate highresolution digital terrain models(DTMs).To generate DTMs,point measurements from non-ground features,such as buildings,vegetation and vehicles,have to be identifed and removed while preserving the terrain points.This paper proposes an efcient mathematical morphology-based multi-level flter to generate DTMs from airborne LiDAR data.Preliminary non-ground points are frst identifed with the characteristics of the multiecho airborne LiDAR data.The localized mathematical morphology opening operations are then immediately applied to the remaining points.By gradually increasing the window size of the flter and using a dynamic critical gradient threshold,the non-ground points are removed,while the ground points are preserved.Eight samples were chosen from eight sites provided with the ISPRS Commission III,Working Group 3,to evaluate the accuracy of our algorithm.Both the qualitative and quantitative experiment analyses show that our morphologybased multi-level flter method achieves promising results,not only in flat urban areas but also in rural areas,especially in preserving complex terrain details,while non-ground spatial objects are removed. 相似文献
919.
920.
In commercial networks, user nodes operating on batteries are assumed to be selfish to consume their resources (i.e., bandwidth and power) solely maximizing their own benefits (e.g., the received signal-to-noise ratios (SNRs) and datarates). In this paper, a cooperative game theoretical framework is proposed to jointly perform the bandwidth and power allocation for selfish cooperative relay networks. To ensure a fair and efficient resource sharing between two selfish user nodes, we assume that either node can act as a source as well as a potential relay for each other and either node is willing to seek cooperative relaying only if the datarate achieved through cooperation is not lower than that achieved through noncooperation (i.e., direct transmission) by consuming the same amount of bandwidth and power resource. Define the cooperative strategy of a node as the number of bandwidth and power that it is willing to contribute for relaying purpose. The two node joint bandwidth and power allocation (JBPA) problem can then be formulated as a cooperative game. Since the Nash bargaining solution (NBS) to the JBPA game (JBPAG) is computationally difficult to obtain, we divide it into two subgames, i.e., the bandwidth allocation game (BAG) and the power allocation game (PAG). We prove that both the subgames have unique NBS. And then the suboptimal NBS to the JBPAG can be achieved by solving the BAG and PAG sequentially. Simulation results show that the proposed cooperative game scheme is efficient in that the performance loss of the NBS result to that of the maximal overall data-rate scheme is small while the maximal-rate scheme is unfair. The simulation results also show that the NBS result is fair in that both nodes could experience better performance than they work independently and the degree of cooperation of a node only depends on how much contribution its partner can make to improve its own performance. 相似文献