Showing papers in "Modern Defence Technology in 2008"

Sensor Management Algorithm Based on Genetic Algorithm

Abstract: The questions that the characteristic and the existing question of multi sensor multi target management algorithm are analyzed.And combined the thought of genetic algorithm,a sensor management algorithm is presented to serve as the efficacy with jointly error covariance of the target,and the algorithm is proved.The simulation indicates that the sensor management algorithm based on the genetic algorithm is active,and is more applied than the planning method possesses when especially the question scope is bigger.

A Radar Emitter Identification Method Based on Pulse Match Template Sequence

Abstract: In the dense emitter signal environment,the existing radar emitter identification methods can not effectively and rapidly give the class of radars with complex modulation signal.So a new radar emitter identification method based on pulse match template sequence is proposed and the parallel structure and algorithm of this method are given.In different emitter signal environment,the class of emitter can be identified with less computation complexity based on this method.In the end the method is simulated through computer,the result of simulation shows that the method can rapidly and effectively identity the class of radar emitter.

Space-Based Infrared System and the Analysis of its Detecting Capability

Abstract: Early warning satellite system is important components of defense system,and the study of its status and detecting capability has great signality.Contraposing the SBIRS of NMD system,the deve-lopment status and the working progress of SBIRS are introduced.And then according to the parameters of the satellites and its sensors,the work progress of SBIRS is simulated with STK.Finally the detecting capability of SBIRS is analyzed based on the simulation results.

Current Status and the Development Trend of the GNSS

Abstract: A general review of modern global navigation satellite system(GNSS) system is presented.Four kinds of GNSS systems technology(GPS,GLONASS,GALILEO,BD)are analyzed in detail separately.The differences between the four GNSS systems synthetically are compared,then the prospect of the GNSS system's development is predicted.

Influence of Atmospheric Ducts on Radar Distance and Height Measurement

Abstract: Base on the theories of radial in the geometry optics,a mode to evaluate the influence of atmospheric ducts on radar distance and height measurement is established,and the errors of radar measurement in different distances and heights is given,finally the mode is proved throw experiments.A theory is established basement on how to use radar in the conditions of atmospheric ducts,and will be made for the exertion of electronical equipments.

Radar Signal Parameter Feature Extraction Algorithm Based on Entropy Optimal Classification

Abstract: The parameter feature extraction of radar signal is a key step in electronic intelligence system and usually adopts histogram method,but there has a key and difficult problem that is the optimal classification problem and this problem has decisive effect on histogram.The histogram algorithm based on entropy optimal classification criterion is proposed according to the physical meaning of entropy and its basis characteristics.The simulation experiment shows the method is effective to extract parameter feature of radar signal.

Present Analysis and Development Trends of Fuzzy Control Techniques

Abstract: Fuzzy control is an important part of intelligent control.The development and the application of fuzzy control is looked back.The principle of fuzzy control as well as the step of the design of fuzzy controller is introduced.According to the different way of the application of fuzzy control,the types and the different results of different fuzzy controls are analyzed.The strong points as the short point are summarized;the further research of fuzzy control is also presented.The tendencies of fuzzy control are out looked.

Approach Combining with Radar Direction Finding of Solving Ambiguous Location with High PRF Signal

Abstract: Aiming at the ambiguous location of high pulse repetition frequency(PRF) signal,a new approach combining with radar direction finding is put forward in the paper.According as radar netting and partition to airspace,the approach is able to reduce false time difference of arrival(TDOA) extraction and improve ambiguous location effectively without high precise direction finding accuracy.

Designing Variable Structure Guidance Low for Sidewindow Detection

Abstract: To solve the problem of space interception for sidewindow detection,the orbit equation for interception is given.And according to the need of stabilizing the vision angle,a adaptive variable structure guidance law which uses line of sight angle and line of sight angel velocity as the variables is applied to simulate considering the math model of orbit engine and intercepor kinematics.Simulation results got effective result of the space interception and verified the guidance law.

Study of Low-Altitude Antimissile Damage Zone of Network Centric Ship to Air Missile

Abstract: It is necessary to study the damage zone for analysing low-altitude antimissile efficiency of ship to air missileFirst,the decisive factors of network centric ship to air missile damage zone are gi-venTow different damage zones of ship to air missile at low-height anti-missile operation is described with certain initializationsFinally,comes up that the network centric ship to air missile damage zone is a dynamic area comparing with single ship′s

Analysis of the Collocation and Detection Performance of the Passive Radar/Radar Combined Detection System

Abstract: Based on the system which was composed by the passive radar and T/R radar,a mathematic model is put forward for the passive radar/radar combined detection system.The combined target detection precision and the distributing of the fuzzy zone of the four kinds of location projects are analyzed.The detection performance of the passive radar/radar system and the passive radar system is compared.The simulation shows that the optimal collocation project of the combined detection system is that the structure of the passive radar detection system is "Y" and the T/R radar is 10~40 km away from the back of the passive radar,and then the target detection precision is most precise and the fuzzy zone is smallest.

Queuing Theory Based Evaluation of Ship to Air Missile System Group Operational Effectiveness

Abstract: In the modern sea-borne military war,it is very important to research to ship air missile system group,because of its great importance.The operational efficiency of ship air missile is evaluated by using queuing theory.Queueing theory and estimate of the system group in the jamming case is presented.The curve of intercept probability and penetration probability is drawn.In the end,based on the curve three conclusion is given.

Combined Navigation of Computational Vision and SINS Based on Kalman Filter

Abstract: After introducing what are computational vision and computational vision navigation,an combined navigation method of computational vision and SINS is brought out,since the reference marks on earth are three dimensional,and what computational vision get are two dimensional images,methods of imaging and coordinates conversion are discussed,then the combined navigation method is analyzed in detail,error equations are set up,and a filtering algorithm based on Kalman filter is proposed.Simulation results show that the navigation method can improve the guidance precision and is useful.

Study on Interferometer Ambiguity Resolution

Abstract: Ambiguity resolution is always a problem with attention in the interferometer technology.Based on stagger baseline length,multiple frequency,mono-pulse,ranging,baseline rotation and frequency modulation,six different ambiguity resolution techniques are studied,and the realizability and the complexity for each technique are compared.Furthermore,a universal algorism for these ambiguity resolution techniques is developed.

Passive Location to Moving Emitter Using DOA and Its Rate of Change

Abstract: The theory of passive location to moving emitter on the ground using DOA(direction of arrival) and its rate of change are described.Expression of observability is obtained by Jacobi matrix and conditions of observability under different relative motion states are discussed.A location algorithm which involves DOA and its rate of change based on MGEKF(modified gain extended Kalman filter) are put forward,and comparisons with the location algorithm only using DOA and other classic algorithms EKF are also given respectively according to simulation results.

Study on the Compatible Electromagnetism of Shipboard Aerial Defence Weapon System Cooperative

Abstract: In order to improve ability of warship boat,aiming at the characteristic of shipboard aerial defence weapon system,the compatible electromagnetism is research from three aspects including airspace,time-domain and frequency domain.The cooperative flow is put forward.It has important instruction meaning.

Experimentation Investigation of Blast Effect of Explosive Charge with Different Shell Material in Air

Abstract: The blast effect is researched in the present paper by the means of experimental investigationIn the case of the same explosive charge,the peak overpressure caused by the detonation of explosive charge with composite material shell is higher than that with steel shellBecause of no fragment generated in the case of explosive charge with composite material shell,the distant target is not affected by the fragment effectHowever,the reverse condition takes place in the case of explosive charge with steel shell

Design and Simulation of SAR Satellite Orbit Prediction Based on STK

Abstract: The SAR(synthetic aperture radar) satellite can reconnoitre the specific area all-weather and all-position.The orbit prediction of the SAR satellite is the precondition of anti-satellite.At first,the database of the SAR satellite is founded.The circulate and real-time coverage to the ground by connecting the database to the STK(satellite tool kit) with the module of STK/connect was showed.A visiting report can be gotten by the system function of creating report.Orbit prediction of the area of the SAR satellite can be made through the report.

An Evaluation Model of Fire Efficiency on Air Defense System

Abstract: On the basis of establishing evaluation principle in fire efficiency,an evaluation method of fire efficiency on air defense system is inquired,an ordinary mathematical model is established Major factors is also founded based on the given mathematical model.As a result,relational expression is obtained about the decline in the integral fire efficiency of air defense system between each integrant of air defense system.

Coherent Jamming Technique Countering Frequency-Stepped Chirp Signal ISAR

Abstract: The inverse synthetic aperture radar(ISAR) possesses high processing gain,so jamming to it is more difficult than it to the conventional radar.The frequency-stepped chirp signal is very common in ISAR imaging because of its peculiar characters.A coherent jamming method to frequency-stepped chirp ISAR is presented.The radar signal is transmitted back with additional frequency and phase modulations.As a result,the ISAR image will be jammed when the radar receives the modulated signal.This method requires lesser jamming power compared to conventional noise jamming.A computer simulation is given to prove the effectiveness of the proposed method.

Graphics Processing Algorithm for Complex Areas in Power Simulation of Radar Network

Abstract: Regarding the complex detection areas in practical position of radar network as research object,some algorithm is put forward,such as "eraser" arithmetic to fill the complex planar detection areas of radars,area calculating algorithm,and verge picking algorithm of planar detection areas of radar network.Simulation is made to validate the algorithm,and results show that the algorithm is effective.The algorithm can be widely applied to power simulation of radar network and other correlative field.

Assessment on GMD's Deployment Status and Operational Capability

Abstract: The deployment status of gound-based midcourse defense(GMD) is discussed in this paper,as well as the abilities of its subsystemsIn particular,the early warning capabilities,the ability to predict and identify target's trajectory,extroatmospheric kill vehicle(EKV)′s homing ability and battle management,command,control and commnication(BMC3)′s organizational and conmmunication capability are also been briefly presentedMoreover,with the inculsion of the results from the official interception tests,the operational capability of the current GMD system is evaluated

Current Technology and Development Trend of Kinetic Missiles

Abstract: The current technology and development trends of ballistic missile defense is introduced.As the earlest national to devolop kinetic kill technology,U.S.has deployed ground-based interceptor(GBI),standard missile-3(SM-3),patriot advanced capability-3(PAC-3) missile,and begain to manufacture terminal high-altitude area defense(THAAD) system,and has made great progress on the developing kinetic energy interceptor(KEI) multiple kill vehicles(MKV) technology.Now kinetic weapons have had initial missile defense capabilities,and become the most advanced,effective,available and accurate weapons for ballistic missile defense in the world.

Tracking Method of IR Small Target Based on Particle Filter

Abstract: A track method of infrared small target based on particle filter is proposed.First according to the characteristic of the infrared small target,grey statistics histogram distribution model is established to the description to the target,the distance based on Bhattacharyya coefficient is adapted to carry on the similar measure,and the goal observation model is established.Then particle filter and mean shift are combined using the model to track the infrared small target.Tracking experiments is presented in which our method successfully coped with partial occlusion of target in the image sequence process,and the infrared small target can be tracked accurately.

A Method for System Error Correction and Precision Analysis in Radar Network System

Abstract: System errors influence data fusion precision,so the error crrection method based on ECEF in radar network is put forward,the method to evaluate the estimate precision of system errors is defined,CRLB is adopted to evaluate the estimate precision of system errors.At last,the simulation validated that the error crrection method was viable and the evaluation method for estimate precision was effective.

Date Link Scheme of UAS Base on Technologies of Low Earth Orbit Satellite

Abstract: Based on the technologies of low earth orbit(LEO) satellite communication,the date link model of satellite communications is presented for the high attitude and long time unmanned aircraft system(UAS).The limitation of the conventional date link is analyzed and the advanced communication technique is be used in the paper.The date link scheme of UAS is given via using the advanced coding technologies.On the condition of the UAS' operation,the ability of information transmission and security of date link scheme will be improved.

Application of Genetic Algorithm in Structural Modal Parameter Identification

Abstract: The linear structure system modal parameters identification based on genetic algorithms is studiedgenetic algorithms has been well studied in generalization dynamics system identification,but less work has been done in the structural system identificationTherefore,based on floating point coding,the steps of structural model parameter indentification using the frequency response data are givenBecause of the global optimization of genetic algorithms,the method has good quality of resisting noiseThe result is validated by simulating of a two degreeof freedom mass-spring-systemFinally proposed method is used to identifying modal parameter of the missile structure

Air Defense Efficiency Evaluation Under Complicated Electromagnetism Environment Based on Analytical Hierarchy Process

Abstract: To consider the air defense electronics equipment application under the complicated electromagnetism environment,the analytical hierarchy process method is used to research and studyThe layer analysis method effect evaluation model systematically is set upThe evaluation index system is put forwardThe relative weighting of each layer is calculated,the index quantity believable degree of the first floor is also calculatedThe method is validated using real experimentAt last,it makes an outlook for the measures of the theory

The Analysis and Simulation of LFM Pulse Compression Radar Antijamming Ability

Abstract: Pulse compression radars have strong ability of antijamming.Integrated with the working process and antijamming theory of linear frequency modulation(LFM) pulse compression radar,the characteristics of noise amplitude modulation amplaupude jamming,noise jamming,noise frequency modulation(FM) jamming and shift-frequency jamming are analyzed,antijamming ability of pulse compression radar is discussed.At last,simulation results and conclusion are gained.