passive location of ssr using tdoa and angle information by ml and wmse criterion via single site and experimental results

due to increasing growth of air traffic, it is very important to have a reliable air traffic control system. usually secondary surveillance radar systems are employed for this task. in this paper, a new approach is presented to identify interrogators location of this system. the proposed method works passively and uses just a single receiver. this goal has been reached using angle and time difference of arrival information. how to determine the desired angle and calculate the time difference of arrival from the received data is described. knowing this information, a closed-form solution in polar coordinate is presented and its sensitivity is measured. then a method is proposed based on maximum likelihood estimation of the target location. afterward angle and time difference of arrival equations are linearized and then weighted least squares estimation is achieved. the suggested approach is evaluated on real and practical information and the results have finally been reported.