Wide Area Based Precise Point Positioning

Precise point positioning (PPP) is a positioning technique in which a single receiver is used to determine its coordinates,using precise products such as orbits and clocks. In this work we are discussing the ambiguity parameter in PPP, which, for several reasons, is not an integer value, as it happens in case of double differenced observations The ambiguity parameter in PPP includes satellite and receiver biases, which have to be adequately separated in order to obtain integer ambiguities, what would allow ambiguities fixing process. In order to do so, a new approach was introduced, called here wide area precise point positioning. The main idea of this new approach the determination of satellite fractional biases using a network of receivers. In order to separate fractional biases from other parameters such as ionospheric delays and ambiguities, a de-correlation filter was created, and in experiments carried out involving nearby stations, the ionospheric delays determined with the de-correlation filter agree very well with each other Differential receiver-satellite fractional biases were determined for former IGS station and PRN 20 at L1 frequency and showed to be stable with a mean value of 0.6 cycles, and standard deviation of around 0.2 cycles. This uncertainty in metric units for L1 frequency is 3.9 cm.