With an RTK correction extension service, an operator’s receiver will automatically transition to the L-Band source for correction data when an RTK signal is lost. The receiver will utilize that L-Band correction until normal RTK corrections are recovered, a timeout is reached or position accuracy degrades beyond a defined threshold. All corrections are handled seamlessly in the background and these services automatically compensate for datum differences and related biases between correction sources. As with any carrier phase positioning, position jumps may sometimes occur depending on the quality of the ambiguity fix prior to the dropout.
While durations may vary depending on the service provider, users are typically able to maintain RTK level performance and accuracy during an outage for up to 20 minutes as long as there is L-Band tracking and the GNSS receiver has had at least one RTK fix prior to the outage. Some providers also offer RTK correction outage bridging that operates at a sub-decimetre level of accuracy.