Modified GPS/Pseudolite Navigation Message

Abstract

One of the issues regarding integrated GPS/pseudolite measurements is how to deliver a pseudolite's position to a receiver or to post-processing software and how to manage it. This paper presents a proposed solution to this problem. The standard navigation message is modified in such way that without changing receivers (or post-processing software), the calculated position of a transmitter is fixed at a pseudolite's known position. The formulae for modification of standard Ephemeris Data are also derived. This algorithm can be implemented in a transmitter's firmware or a navigation data file can be modified for post-processing.