Interference coordination is one of the effective methods to mitigate Inter-Cell (ICI) in OFDM system. An ICI technique based on users' ratio and frequency allocation proposed this paper. Firstly, it guaranteed that cell-edge users neighbor cells are not interfered by each other. Then, resources which allocated users, rest can be cell-center with two levels power. Simulation results show our algorithm improve whole system performance, especially throughput performance.

Abstract Active clearance control has been used to improve efficiency and performance in commercial aircraft engines. This paper describes a optical fiber sensor for active control, which is simple thin structure. The system data sampling rate about 100 kHz, its resolution ratio better than 0.01 mm. Sensor's ability monitor tip was tested using rotor test rig individual blade clearances at different speed failure measurement example given. results show: the able detect flaws, have large...

Purpose The purpose of this paper is to solve the tracking problem for free-floating space manipulators (FFSMs) in task with parameter uncertainties and external disturbance. Design/methodology/approach In paper, novel cerebellar model articulation controller (CMAC) designed feedback controller. More precisely, FFSM are considered achieving robustness. Findings By using dynamically equivalent model, CMAC can be trained desired performance, such that prescribed trajectory followed...

In this paper, a method of predicting the motion state moving target in base coordinate system by hand-eye vision and position attitude end is proposed. The predicted value used as velocity feedforward, position-based visual servo to plan manipulator. It overcomes influence on prediction discrete introduces an integral control compensate for velocity, eliminating tracking error caused error. effectiveness verified simulation experiment.

Recent progress on development trend and key technologies of vertical take-off landing reusable launch vehicle

Unmanned airship possesses some advantages, such as long time hovering, much less energy consumed and cost efficiency. It is becoming one of the focus interests in field unmanned viechles. An onboard controlling system was designed this paper, which microcontroller corresponding peripherals are included. With STC12C5A60S2 central unit, detail including MCU, ultrasonic sensor, compass, battery moniter circuit, alarming signal generation so on. At last, flowchar sofware presented. From...

As a near orbit space platform, the International Space Station (ISS) has been increasingly used for Earth observing applications. This paper presents quaternion-based forward geolocation algorithm sensors onboard ISS. The input parameters include orbital state and attitude information of ISS look vector sensor. proposed agrees with commercial navigation product, Satellite Tool Kit®, within 0.5 m in ideal situations. inherent uncertainties determinations, Agriculture Camera (ISSAC) tilting...

A geometric modeling and solution procedure for direct kinematic analysis of 6-4 Stewart platforms with any link parameters is proposed based on conformal algebra (CGA). Firstly, the positions two single spherical joints moving platform are formulated by intersection, dissection, dual basic entities under frame CGA. Secondly, a coordinate-invariant equation derived via CGA operation in other pairwise joints. Thirdly, five equations terms constraints. Fourthly, 32-degree univariate polynomial...

Abstract An integrity monitoring of integrated navigation in the presence slowly growing errors (SGEs) is proposed. SGEs with gradual growth over time are worst category latent failures. Tightly coupled inertial system (INS)/Global Navigation Satellite System integration presented by taking INS errors, bias and drift receiver clock, baro‐altitude, pseudo‐range ionospheric into consideration. Based on RTCA performance standards DO‐229 DO‐384, simplified multi‐filters solution separation...

In this paper, a novel integrated flight control and flow system using synthetic jet arrays is presented. the proposed system, active actuator, synthetic- jets-instrumented-wingtips were designed to enhance or replace traditional roll of specified airplane. Wind tunnel experiments conducted obtain dynamic model synthetic-jets-instrumented-wing-tips. A closed-loop was developed reattach at high angle attacks. fidelity for airplane with synthetic-jets-instrumented-wing-tips based on wind...

Intelligent control of space manipulator with flexible-link and flexible-joint is discussed based on the singular perturbation method. Owing to combined effects link joint flexibilities, dynamic model this kind becomes more complex leads a series unsolved system. To simplify design system, method used obtain two-time-scale simpler subsystem composite designed realize precise trajectory tracking vibration suppression simultaneously for flexible-link/flexible-joint payload. In slow subsystem,...

An effective method is proposed for calculating the on-board real-time path planning of large-scale space redundant manipulators. Firstly, 7-DOF manipulator kinematics model described and analyzed, main computational process presented. The homogeneous transformation matrices various degrees freedom are obtained through telemetry joint angle, used to calculate Jacobian matrix pseudo inverse angular velocity each joint. Then, according theoretical analysis, hardware design structure based on...

At present, there are some problems in the detection and evaluation test of several large caliber guns. For example, data abnormal sensors damaged abnormally. Through analyzing recoiling movement gun recoil brake, according mathematic model movement, indicate reason why interior chamber pressure has a error between traditional calculation firing test. Propose an indirect testing calculating method for brake. That is based on QPSO, correct hydraulic resistance coefficient bring modified...

In order to enhance the efficiency of dynamics modeling modular space manipulator, a kind efficient method based on Space Operator Algebra is proposed in this paper. The application and advantages manipulator compared conventional are introduced first. And then, conceptual design basic modules provided mathematical relationship between each module described by transformation matrix. Thereafter, high which has characters concise format programming. Finally, simulation for 7-DOF carried out...

Space intelligent robotic systems are expected to play an increasingly important role in the future. The on-orbital service, whose key is tracking and capturing technology, becomes research hot recent years. In this paper, authors propose a vision servo control system for target capturing. Robotic manipulator will be with large-scale movement, functional agility, autonomous ability, it can operated by astronauts space station or controlled ground operator remote operation mode. To realize...

Abstract In the inertial navigation system (INS)/ air data (ADS) integrated system, measurements of INS and ADS need to be converted a unified coordinate for fusion. However, sensor noises cause serious conversion bias in direct measurement method. this paper, novel INS/ADS method based on error model-aided unbiased (IEM-UCM) is proposed. First, IEM-UCM model from spherical frame developed, which exploits calculate compensation factors. Subsequently, noise covariance derived. Finally,...

Abstract In civil aviation systems, the inertial measurement unit (IMU)/Global Navigation Satellite System (GNSS) integrated navigation remains most effective scheme. Based upon this, utilization of redundant IMUs and a multi-constellation system can significantly enhance integrity performance. However, IMUs/GNSS systems are susceptible to more complex failure modes, including GNSS faults (satellite constellation faults) IMU faults. Additionally, dealing with correlated measurements between...