Rapid convergence of precise point positioning (PPP) solutions to cm‐level precision is a key factor for many applications. One means of accelerating this convergence is to exploit the benefit of information on the ionosphere. In order to preserve the integer nature of carrier‐phase ambiguities in PPP, it is imperative that ionospheric corrections be provided with a set of compatible satellite phase biases. When using the decoupled‐clock model, global ionospheric maps (GIMs) currently provided by the International GNSS Service are not directly applicable to PPP with ambiguity resolution. This paper describes a methodology for incorporating external ionospheric corrections into this model. It is shown that the use of both GIMs and ambiguity resolution can potentially reduce the convergence time of PPP to 10‐cm horizontal accuracies from 30 to 4.5 minutes (68^th percentile), while a regional network with inter‐station spacing of 150 km can reach this threshold instantaneously under favorable ionospheric conditions. © 2014 Her Majesty the Queen in Right of Canada. NAVIGATION. © 2014 the Institute of Navigation.

Precise point positioning (PPP) uses precise satellite orbits, clock corrections and biases derived from a global network of reference stations to enable accurate positioning worldwide. Natural Resources Canada's Canadian Spatial Reference System (CSRS) PPP is a free Web service offering automated PPP processing. A critical factor limiting the adoption of PPP in many applications is the convergence time needed to reach centimeter-level accuracies. To address this issue, CSRS-PPP now implements PPP with ambiguity resolution (PPP-AR). This feature required the development of new algorithms, such as sequential normal stacking for least-squares filtering/smoothing, and the weighted integer decision concept for ambiguity validation. New satellite product lines (ultra-rapid, rapid, final) also have been deployed to enable PPP-AR processing with various latencies. This analysis demonstrates that sub-centimeter horizontal accuracies can be obtained in less than one hour for both static and kinematic modes. Using product lines with longer latencies is beneficial, although improvements are typically within the reported uncertainties.