NEXA is a robust non-linear least-squares generic sequential estimation engine. With NEXA, trajectories of any type –i.e., time series of parameters– can be computed from given measurements (input data) and from the mathematical models that relate the measurements to the [unknown] parameters (input software).
A typical application of NEXA is the fusion of inertial measurements and satellite-to-receiver distances, a.k.a. INS/GNSS integration. NEXA can be used in real-time or post-mission modes. It can be used with real or simulated data for trajectory determination and system design respectively.