Multilateration Software Development.

This report documents the initial results of a software development directed at identifying a common navigation system data processor which would be more or less equally applicable--with appropriate tailoring--to any radio-inertial, radio-autonomous, radio-dead reckoning, or barometric-inertial navigation system. A functional processor has been defined which is potentially applicable for use for any of a wide class of military and civil missions, and radio and inertial equipment types. To achieve this generality and flexibility, algorithms were selected primarily on the basis of their 1 system-to-system generality, 2 mutual commonality, 3 functional modularity and 4 compactness of expression. These qualities will facilitate the eventual realization of easily programmable, interchangeably common, navigation system software units. In particular, vector-matrix formulations were identified and used for a very large percentage of the processor algorithms, including a central Kalman filter, which was incorporated in the processor to enable near-optimal mixing of the available radio, inertial, and other navigation data. A set of basic navigation and navigation error equations were also identified and incorporated in the processor these equations can be used unchanged for navigation and with respect to either a global or a local-tactical corrdinate reference frame.