Research On Passive Localization Based On Tdoa Using Coordinated Uavs

In the battlefield of modern informatization,electronic reconnaissance,as a "clairvoyance" in war,plays an important role.Passive positioning technology,as an important function of electronic reconnaissance,has a status that cannot be ignored.In recent years,drones have repeatedly appeared on the battlefield and have attracted people’s attention.This paper focuses on the method of UAVs positioning the radiation source target based on time difference of arrival,from the perspectives of time delay estimation,positioning solution,and multi-target data association.First,explore the principle of using the time difference observation information to solve the target position,and study the time difference measurement method.Research on the multipath problems that may appear in the UAVs combat scenario.Explore the algorithm of how to reduce the time difference measurement error in the multipath environment.Introducing the correlation entropy theory,when the signalnoise ratio is low,the accuracy of the estimated time delay is improved by about 10%.Subsequently,a model for the positioning of a single target by the UAVs was established,the Cramer-Rao boundary and the geometric precision factor were derived,and the positioning method,number,height,and relative position of the UAVs were analyzed for the positioning accuracy influences.Consider the problem of the conversion between the geodetic coordinate system and the spatial rectangular coordinate system when using the UAVs to realize passive positioning.The solution methods of TDOA single target positioning are studied,including Chan algorithm,Taylor algorithm,and particle swarm algorithm.In order to solve the problem of drone clusters as a highly mobile platform with greater site errors,the above algorithm is improved under the condition of the UAV’s own position error,and a single target positioning solution method based on particle swarm Taylor collaboration is proposed.After the simulation experiment verifies,the Cramer-Rao bound can be realized when the site error is small.When the site error is large,the RMSE error is reduced by about 300 m compared with other algorithms.Finally,a model of multi-target positioning by UAVs is established,and the solution method of multi-target positioning is studied in the case of site errors.Explore the application of information field theory in realizing multi-target time difference positioning.Using the method of data association again,the complex multi-target positioning is transformed into multiple single-target positioning,and a data association algorithm based on adding auxiliary stations is proposed to match the time difference value,compared with the traditional four-time difference data association method,and the correct association rate of the target is increased by 10%about.An analytical algorithm that assumes the location of the source is then used to modify the positioning results of multiple targets,and the improved estimate is closer to the Cramer-Rao bound.