Triple carrier precise point positioning (PPP) using GPS L5

Abstract

The latest generation of GPS satellites, block IIF, include for the first time a new civil signal on L5 frequency (1176·45 MHz), in addition to the legacy signals on L1 (1575·42 MHz) and L2 (1227·60 MHz). Traditional precise point positioning (PPP) is based on L1/L2 dual-frequency observations to remove the ionospheric delay. However, L5 presents interesting properties, such as more robustness against interference compared to L2, which makes it suitable for critical applications. Therefore, navigation users can already start making use of the L5 signal, to increase reliability and redundancy for the most demanding applications. This article addresses the integration of the new L5 pseudorange and carrier phase observables in PPP, which at the same time allows to perform efficient signal characterisation. In particular, ionosphere-free combinations including L5 are explored and their corresponding observation equations introduced. Practical results using IGS MGEX observation data are presented.