Multistatic radar Doppler estimation for passive coherent location

The availability of multiple transmitters in a passive coherent location (PCL) scenario allow for multistatic velocity estimation. This paper develops the mathematical framework and methods to estimate the velocity vector for a target in motion for a passive coherent location system. The developed methods show that there is an analytical solution to combine multiple bistatic measurements in different range and velocity domains for a velocity estimation in the global domain. The multistatic velocity estimation is compared to the traditional multi-time step bistatic PCL velocity solution. The conventional bistatic PCL velocity measurement requires two time steps of measurements, whereas a multistatic solution requires one. This can cause velocity measurement errors for a target with complex motion since the bistatic measurement will not be applicable at the next time step. The methods were tested in simulation for varying motion models, and experimentally verified for the simple linear motion constant velocity test case. The results show that the bistatic time method fails for complex target motion and the multistatic method is capable of determining velocity information in a single time step, as well as superior performance for complex target motion.