数字域谱估计的GNSS系统信号带宽测试方法

针对传统的单载波扫频法不适于GNSS（全球导航卫星系统）信号生成通道的带宽测量的问题,提出了采用数字信号处理的信号带宽方法.对实际导航信号进行高速采样,在数字域对采样的导航信号和本地数字生成的理想导航信号进行频谱估计和计算,从而得到GNSS信号带宽.分别使用周期图法和Welch法谱估计,对提出的测试方法进行仿真.仿真结果表明,采用Welch法进行理想信号和实际信号谱估计,对谱估计后的结果进行计算,可以完成GNSS信号带宽精密测量,在Welch法估计参数设置合理的情况下,GNSS信号带宽估计的准确度可以达到99.9％以上.     

Design and analysis of a truss deployable antenna mechanism based on a 3UU-3URU unit

Space deployable structures with large calibers, high accuracy, and large folding ratios are indispensable equipment in the aerospace field. Given that the single-DOF 3RR-3RRR deployable unit cannot be fully folded, this study proposes a 3UU-3URU deployable unit with two kinds of DOF: folding movement and orientation adjustment. First, based on the G-K formula, the DOF of the 3UU-3URU unit is analyzed. Then, the 3UU-3URU unit is used to construct a deployable truss antenna with a curved surface, and the DOF of the whole deployable antenna containing multiple 3UU-3URU units is calculated. The structural design of a deployable antenna with two loops is carried out with specific parameters and geometric relations. Next, a DOF simulation of a basic combination unit composed of three 3UU-3URU units is performed. Finally, a prototype of the basic combination unit is manufactured, and the DOF of the mechanism is experimentally verified.     

多品种变批量产品智能制造系统框架

YU Chenglong;HOU Junjie;ZHAO Ying;XU Hao;ZHANG Wei(China Aerospace Academy of Systems Science and Engineering, Beijing 100048, China)     

集成管理系统在飞机装配柔性工装上的应用

采用柔性工装对飞机零组件进行装配,会产生巨大的信息量,为提高飞机装配过程的信息管理的质量与效率,目前采用集成管理系统对飞机装配柔性工装进行控制与管理,来实现飞机装配过程的集成化。对集成管理系统在飞机装配柔性工装上的应用进行研究,首先对集成管理系统的构架、数据格式以及通信接口等进行概述;之后对柔性工装的数据传输与调形驱动过程进行分析,对飞机柔性装配技术体系进行总结;最后对集成管理系统在柔性工装上的应用现状进行研究。研究表明,集成管理系统可以提高柔性工装的装配效率与信息管理质量。     

Distributed state estimation for heterogeneous mobile sensor networks with stochastic observation loss

The problem of distributed fusion and random observation loss for mobile sensor networks is investigated herein. In view of the fact that the measured values, sampling frequency and noise of various sensors are different, the observation model of a heterogeneous network is constructed. A binary random variable is introduced to describe the drop of observation component and the topology switching problem caused by complete observation loss is also considered. A cubature information filtering algo...     

机载自相关监视系统的一种新的设计方案

提出了自相关监视(ADS)系统(机载部分)的一种设计方案.该方案包括ADS系统多信息源的处理、ADS信息机内传输及ADS信息在空地子网络中的传输.     

海上多平台传感器管理与控制的设计与实现

以实现对海上多平台传感器资源进行自动或半自动的协调管理控制为目标,设计了传感器管理与控制系统的功能结构,对组成系统的传感器信息管理、传感器组织管理、收发通信管理、传感器控制管理和传感器综合效能分析等功能模块进行了描述,采用基于效能函数的多传感器管理算法实现了传感器的任务规划与资源分配,并采用"集中管理,分散控制"的方式进行海上多平台传感器的管理与控制。     

Geostationary orbit determination using SATRE

A new strategy of precise orbit determination (POD) for GEO (Geostationary Earth Orbit) satellite using SATRE (SAtellite Time and Ranging Equipment) is presented. Two observation modes are proposed and different channels of the same instruments are used to construct different observation modes, one mode receiving time signals from their own station and the other mode receiving time signals from each other for two stations called pairs of combined observations. Using data from such a tracking network in China, the results for both modes are compared. The precise orbit determination for the Sino-1 satellite using the data from 6 June 2005 to 13 June 2005 has been carried out in this work. The RMS (Root-Mean-Square) of observing residuals for 3-day solutions with the former mode is better than 9.1 cm. The RMS of observing residuals for 3-day solutions with the latter mode is better than 4.8 cm, much better than the former mode. Orbital overlapping (3-day orbit solution with 1-day orbit overlap) tests show that the RMS of the orbit difference for the former mode is 0.16 m in the radial direction, 0.53 m in the along-track direction, 0.97 m in the cross-track direction and 1.12 m in the 3-dimension position and the RMS of the orbit difference for the latter mode is 0.36 m in the radial direction, 0.89 m in the along-track direction, 1.18 m in the cross-track direction and 1.52 m in the 3-dimension position, almost the same as the former mode. All the experiments indicate that a meter-level accuracy of orbit determination for geostationary satellite is achievable.     

基于支持度的MEMS陀螺信息融合方法

为了解决微机械电子系统(MEMS, micro electronic mechanical system) 惯性器件测量准确度低、噪声大、长时间单独使用导航误差积累大等缺点,提出了一种MEMS陀螺阵列结构设计,在完成微型惯性测量单元(MIMU, micro inertial measurement unit)的标定后,采用基于支持度的信息融合方法对陀螺阵列输出进行信息融合。试验结果表明：该结构设计和信息融合方法能够有效的提高MIMU的测量准确度,具有一定的工程应用价值。     

高准确度惯性测量装置全温测试系统的校准

阐述了高准确度捷联惯性测量装置全温测试系统的校准测试方法。通过对软硬件进行校准测试,验证了该系统可以完成不同种类的惯性测量装置误差建模和综合测试。