Non-linear system/linear measurements approach to passive position location using extended Kalman filtering

In solving navigation and tracking problems it has been a widely held view that only the linear system/nonlinear measurement approach is feasible and that it is extremely difficult to derive a non-linear system linear measurements model. Contrary to this view we present here a very simple non-linear system linear measurements model for passive position location problem and apply an extended Kalman filter (EKF) for obtaining position estimates of a stationary emitter. The tabulated results obtained from the Monte Carlo simulations clearly indicate its superiority over the linear system non-linear measurements approach. The problem of a stationary signal being received by a moving aircraft is discussed.