基于多目标优化的星空认知网络鲁棒波束成形算法

卫星通信(SC)网和无人机(UAV)通信网之间频谱共享、相互融合，能较大提升频谱效率，有望成为第6代移动通信的关键技术之一。与现有文献不同，本文在系统非完美信道状态信息(CSI)的条件下，考虑了次级用户可达速率最大化和发射功率最小化2种准则，利用加权切比雪夫方法构建满足概率约束的多目标优化问题(MOO);由于该问题较为非凸，利用概率公式、半正定松弛等方法将其转化为凸问题，并进一步通过半正定规划(SDP)求解，得到鲁棒波束成形权矢量，获得2种性能指标间的帕累托最优权衡。计算机仿真验证了所提鲁棒波束成形算法的有效性和优越性。     

Integrated guidance and control for damping augmented system via convex optimization

In this paper, an integrated guidance and control approach is presented to improve the performance of the missile interception. The approach includes damping augmented system with attitude rate feedback to decrease the oscillation during the homing phase for missiles with low damping. In addition, physical constraints, which can affect the performance of the missile interception, such as acceleration limit, seeker’s look angle, and look angle rate constraints are considered.The integrated guidan...     

安全约束下的空间翻滚目标涡流消旋稳定控制

针对空间翻滚目标涡流消旋任务执行效率低和抵近安全无保证的问题，首先基于椭球包络法给出了服务星机动轨迹的直接线性凸化安全约束，以确保机动过程的安全性和最优轨迹跟踪问题的有限时间可解性；设计了垂直构型下空间消旋任务的抵近期望轨迹以增强服务星消旋力矩的作用强度，缩短任务周期。在此基础上，提出了一种反馈线性化的收缩模型预测控制(FLC MPC)算法，有效跟踪所提出的期望轨迹，并严格保证安全约束及控制输入约束下受控系统的稳定性。最后，利用所提出的控制方法对阿丽亚娜 4火箭上面级进行消旋仿真，结果表明该方法能有效提高消旋效率，并保证服务星的安全稳定。     

Fast calculation method for mission opportunities in orbital interception and rendezvous problems

This paper proposes a fast calculation method to solve all mission opportunities for orbital interception and orbital rendezvous under the impulse-magnitude constraint. Different from the existing search methods, the proposed method does not need to solve Lambert’s problem in the whole process. Three cases are considered for either departure time or transfer time being free, or both being free. For fixed departure time, the feasible windows of transfer time are obtained by solving a single-variable nonlinear equation only of terminal true anomaly. Similarly, for fixed interception (or rendezvous) time, the feasible windows of departure time are obtained. For free departure time and free transfer time, all mission opportunities are obtained by using a one-dimensional search strategy. The hyperbolic-transfer and the multiple-revolution cases are also analyzed. Numerical results show that the proposed method is superior to the typical pork-chop plot method and the two-dimensional launch window method in computational time.     

准双曲面齿轮LTCA弯曲变形约束方法

针对现有准双曲面齿轮加载接触分析（LTCA）受载后得到的弯曲变形中包含由于柔性引起的变形和加载点与轮坯之间剪切变形的问题，提出了轮齿有限元模型约束方法用于消除柔性引起的变形和剪切变形。该约束方法在原有约束方法的基础上引入了约束轮坯内圈和轮齿中间平面的有限元模型，并给出了该约束方法对应的齿面法向柔度矩阵的计算过程。为验证该约束方法的正确性，将原约束方法、该约束方法及实验结果进行对比。结果表明:约束方法主要影响齿面加载接触印迹的范围，最大载荷时原有约束方法加载接触印迹到达齿面小端，而该约束方法的加载接触印迹在最大载荷时距离小端仍有3~4mm与实验结果吻合更好。      

神经网络修正的速度约束辅助车载SINS定位算法

对于车载全球导航卫星系统(GNSS)/捷联惯性导航系统(SINS)组合导航系统，针对GNSS失效而SINS单独工作时仅使用速度约束辅助SINS其纵向位置误差逐渐发散的问题，提出一种神经网络修正的速度约束辅助车载SINS定位算法。通过径向基函数(RBF)神经网络预测SINS纵向位置误差修正系数，以提高SINS单独工作时的定位精度；此外，提出一种限定记忆指数加权实时估计量测噪声的自适应滤波算法。在人为设置GNSS失效以及真实隧道场景下进行车载试验，结果表明本文算法能够在不停车情况下在线修正SINS纵向位置误差，相比于速度约束与卡尔曼滤波相结合的常规算法，有效地提高了GNSS失效时的车载SINS定位精度。     

Three-dimensional time-varying sliding mode guidance law against maneuvering targets with terminal angle constraint

This paper deals with the problem of intercepting maneuvering targets with terminal angle constraints for missiles subjected to three-dimensional non-decoupling engagement geometry.To achieve the finite-time interception and satisfactory overload characteristics, a time varying sliding mode control methodology is developed based on a time base generator function. The main feature of the proposed guidance law guarantees the Line-of-Sight(LOS) angles to converge to small neighborhoods of the desir...     

An improved altimeter-derived gravity anomaly from shipborne gravity based on the mean sea surface height constraint factors method

Coastal marine gravity modeling faces challenges due to the degradation of the quality and poor coverage of altimeter data in coastal regions. The effective fusion of shipborne gravity data and altimeter-derived marine gravity data can make shipborne gravity data more useful for the accurate estimation of altimeter-derived coastal marine gravity. A mean sea surface height constraint factor (MSSHCF) method based on the ordinary kriging method and the remove-restore technique is proposed to fuse altimeter-derived gravity model with shipborne gravity data. In this method, all data are standardized during the interpolation process to reduce the error and mean sea surface as a vertical variable is added to the semi-variance function in ordinary kriging to obtain the residual shipborne gravity as corrected data source. The coastal marine gravity models V2.1 and V3.1 which fused altimeter-derived gravity data with shipborne gravity data and V1.1 without shipborne gravity data at a spatial resolution of 1′×1′ can be obtained. Validation experiments show that the accuracy of the gravity model V3.1 obtained by the MSSHCF method more closely agrees with the validated gravity model DTU17 and SS V31 than the model V2.1 obtained by the ordinary kriging interpolation method and the V1.1 model. Our results were validated against shipborne gravity data; the accuracy of model V3.1 was 4.95 % higher than the model V1.1 in South China Sea area A and 2.48 % higher in South China Sea area B. Meanwhile, the accuracy of model V3.1 was 2.07 % higher than model V2.1 in South China Sea area A and 2.42 % higher in South China Sea area B. The effects of distance from the coast and sea depth on the marine gravity model were also evaluated. The results show that the gravity model V3.1 has higher accuracy with the change in ocean distance and depth than the V2.1 and V1.1 gravity models. Thus, our study shows that the MSSHCF method effectively refines coastal altimeter-derived gravity using shipborne gravity data.     

Formation control for networked multiagent systems with a minimum energy constraint

Minimum-energy formation achievement problems for networked multiagent systems are investigated, where information networks with leaderless and leader-follower structures are respectively addressed and information networks are randomly switching. The critical feature of this work is that the energy constraint is minimum in the sense of the linear matrix inequality, but limited-budget control and guaranteed-cost control cannot realize a minimum-energy formation. Firstly, the leaderless minimum-energy formation control problem is converted into an asymptotic stability one via a nonsingular transformation and state space decomposition, and based on linear matrix inequality techniques, sufficient conditions for analysis and design of leaderless minimum-energy formation achievement are proposed, respectively, which can be solved by the generalized eigenvalue method. Then, main results of minimum-energy formation achievement of leaderless networked multiagent systems are extended leader-follower networked multiagent systems, where the asymmetric property of the leader-follower information network is well dealt with by two nonsingular transformations. Finally, two simulation examples are shown to verify the main results for minimum-energy formation achievements of leaderless and leader-follower networked multiagent systems, respectively.     

基于惯性递推原理的行人自主定位方法综述及展望

在室内环境或者卫星信号遮挡环境下,如何实现单兵或者行人的自主定位是目前研究的热点问题.其中,基于惯性递推原理的行人自主定位方法由于无需提前布设基础设施,且具有体积小、成本低、完全自主、不受干扰、实时性高等特点,因此具有广泛的研究价值和意义.本文围绕基于惯性递推原理的行人自主定位方法展开介绍,针对动态步态分析、零速区间检测、惯性器件误差约束、运动误差约束方法和融合算法等方面技术进行了综述.最后,对基于惯性递推原理的行人自主定位方法的发展方向进行了展望.