Passive vertical tracking using DME multilateration

• Multilateration solution for altitude surveillance • Low cost (8 to 14 receivers) • DME interrogation signal • TOA with Kalman Filter algorithm • Shows the potential of CNS convergence • For altitude accuracy the best receivers distribution is projection (linear) • Vertical accuracy as barometric altimeter (15 m) • Future work and improvements to the model • Modelling of multipath errors • Include the estimate of the clock emitter delay • Use of azimuth sensing antennae in receivers