Compared with a single Unmanned Aerial Vehicles (UAV)the UAV formation of has a better overall performance in cooperative detectionreconnaissance or combat.The task execution lifecycle of UAV formation is divided into six stagesincluding formation formingformation flying toward the task areaformation reconfiguration while flying toward the task areaformation reconfiguration while performing tasks in the task areaformation return and formation dissolution.These six stages are summarized in three key technical issues including formation rendezvousformation keeping and formation reconfiguration.The current situation of study on them is discussed and analyzed respectively.Finallythe future development challenges and research tendency are proposed.

Considering low accuracy even divergence of maneuvering target tracking due to inaccurate tracking model and uncertain statistical propertywe proposed an adaptive Square Root Cubature Kalman Filter (SCKF) based on the standard SCKF and modified SageHusa estimator.The proposed algorithm can estimate the statistical parameters of unknown system noises onlineand restrain the tracking error caused by unknown system noises effectively;hence it is applied to maneuvering target tracking.The simulation results show that:comparing with SCKF algorithm，the adaptive SCKF can provide better accuracy and stability for maneuvering target tracking when the unknown or time variant system noises is some different from the prior noise knowledge.

The firing range of extended range and trajectory correction projectile is the key factor for the projectile to achieve simultaneous impact. In order to study the influence of time control parameter to the firing rangewe established a compound extended range particle trajectory modeland analyzed the influence of the time control parameterssuch as rocket firing time and drag ring openloop timeto the firing range by using digital simulation method. Further morethe fitting functions were established for the influences.A quantitative description method was presented for extended range and trajectory correction projectile to achieve simultaneous impactwhich has important application and reference value.

Threat assessment for the electronic warfare (EW) targets is very important for EW combat decision making.In order to deal with the imprecision and uncertainty of factors relative to EW targets during threat assessmenta multiattribute and group decisionmaking threat assessment model was set upwhich focused on the selection and determination of threat assessment indexes.Based on the scale quantitative functionthe qualitative indexes were quantified.Then the compromise ranking methodVIKORwas used to sort the threat targetsthus to made the overall utility maximum and individual regret minimum.Finallythe effectiveness of threat assessment model and the feasibility of the algorithm were proved through the threat assessment simulated on the supposed view of an EW.

In view of the high computational complexity of the existing joint target tracking and classification (JTC) algorithmwhich has neither closed form nor modular structurewe united the models of all predicted target types to form a global multimodel set.Thenwe proposed a joint target tracking and classification algorithm based on global multiplemodel(GMMJTC) by applying Bayes rule to the target state probability density function and target class probability mass function simultaneously under the assumption that the kinematic and attribute measurement processes are conditional independent.The GMMJTC algorithmwhich consists of a Kalman global multiplemodel filter and a Bayesian classifierhas a closed form with a modularized structuretogether with a lower computational complexity.Its more suitable for realtime applications.The simulation results confirm the effectiveness of the proposed GMMJTC algorithm.

Traditional approach and landing guidance equipments are difficult to meet the urgent needs due to their poor flexibility.Thereforewe studied the continuous navigation project based on DGPS/SINS tight integration according to airplanes requirement to the navigation parameters in the process of approach and landing.In the condition of good GPS signalthrough building up difference base station and transmitting observation data such as pseudorange to rover stationthe DGPS and GPS/SINS tight integration algorithm was processed in receiver terminal.In the case of no satellite signalthe velocity information from SINS was used as observation for dead reckoning the relative positionand the navigation parameters needed for landing were acquired.The experiment results indicate that this method can obtain continuous relative positionvelocity and attitude with high accuracy for airplane approach and landingwhich is useful for practical application.

The sharedaperture thinned interleaved arrays design technology is an important infrastructure of integrated sensor system (ISS).It can reduce the quantity of antennassave spaceand reduce the loads and manufacture costs.The shared aperture interleaved arrays based on difference sets usually have high sidelobe levelsbecause of the asymmetric distribution of the thinned subarrays elements.A method of optimized interleaved arrays was proposed based on difference sets and genetic algorithm.Firstthe difference sets were used to determine the position of array elementsand the current magnitude distribution of arrays was taken as the decisionmaking variable.The genetic algorithm was used to lower the maximum sidelobe levelthus to improve the performance of the whole shared aperture interleaved arrays.The simulation results show that the method is effective to restrain the sidelobe levels and useful for interleaved array optimization.

The airborne multiinput multioutput synthetic aperture radar (MIMOSAR) may have spacevariant range error while enlarging the illuminated areathus result in various imaging error for the existing algorithms applied to the large scale model.This paper presents a theoretical analysis based on the sidelooking modeland the analysis shows that under the widen swaththe mismatch between the echo signal and the reference function is the main factor of the imaging error.So an algorithm of highprecisionlarge region imaging was proposedwhich was verified by the results of simulation.