Patent ID: 8654007
Filing Date: 2014-02-18
Classification: G01S

Abstract:
1. A tracking method for multi-channel radar systems, the system comprising a receiver exploiting the transmissions of a number of utility transmitters, each transmitter forming with the receiver a bistatic base, the transmission produced by each of the transmitters exhibiting a spectrum consisting of different frequency whose treatment leads to each measurement instant in the creation of blips, each blip being characterized by a vector of three measurement constituted by a bistatic distance measurement, a bistatic speed measurement and an azimuth measurement, as well as a 3 ×3 diagonal matrix of the errors associated to these measurements, comprising: a first upstream merging step; applied separately at each bistatic base, operating directly in the space of the components of the vectors characterizing the blips, and implementing an operation to form individual tracks, carrying the identification of the blips of different frequency channels relative to the same target and the instantaneous merging of these blips, the operation to form individual tracks comprising for each measurement instant: a first blip merging substep for associating the individual blips of the various reception channels of each bistatic base which exhibit, for a given measurement instant, measurement vectors y a second substep for constructing individual tracks from the merged blips, an individual track being formed by the succession over time of the merged blips relating to one and the same target, each detected target being represented by a bistatic individual track which characteristics change over time depending on blips associated to it; the blip merging substep using a blip aggregation module which associates the individual blips of various reception channels of one and the same bistatic base which exhibit, for a given measurement instant, measurement vectors y in which (σ R being defined by where r a second downstream merging step generating a global track from individual tracks relating to one and the same target simultaneously detected by several bistatic bases, the second step implementing: a module for initializing new global tracks, a new global track being initialized by combination of two individual tracks elaborated by two distinct bistatic bases a module to maintain the formed global tracks, the maintain being performed by research of individual tracks developed by other bistatic bases which may be associated with an existing global track, individual tracks that can be associated with a given global track being determined by projecting the attributes of the considered global track in each reference coordinate system of the bistatic bases in which no individual track have yet been associated to the considered global track and by comparison, for each of these bistatic bases, of the attribute values of the projected global track to the attributes of different individual tracks relative to the considered bistatic base; and a merging operation of bistatic information of the different merged individual tracks consisting, in a first time, to implement a localization module exploiting bistatic distances of individual tracks to determine an estimate of the position of the global track from ellipsoids corresponding these bistatic distances, then, in a second time, to implement a non-linear filtering module simultaneously exploiting the position estimation performed and bistatic speeds characterizing the individual tracks contributing to the maintain of the global track.