Single-frequency, dual-GNSS versus dual-frequency, single-GNSS: a low-cost and high-grade receivers GPS-BDS RTK analysis

The concept of single-frequency, dual-system (sf-ds) real-time kinematic (rtk) positioning has become feasible since, for instance, the chinese beidou navigation satellite system (bds) has become operational in the asia-pacific region. the goal of the present contribution is to investigate the single-epoch rtk performance of such a dual-system and compare it to a dual-frequency, single-system (df-ss). as the sf-ds we investigate the l1 gps + b1 bds model, and for df-ss we take l1, l2 gps and b1, b2 bds, respectively. two different locations in the asia-pacific region are analysed with varying visibility of the bds constellation, namely perth in australia and dunedin in new zealand. to emphasize the benefits of such a model we also look into using low-cost ublox single-frequency receivers and compare such sf-ds rtk performance to that of a df-ss, based on much more expensive survey-grade receivers. in this contribution a formal and empirical analysis is given. it will be shown that with the sf-ds higher elevation cut-off angles than the conventional $$10^{circ }$$ or $$15^{circ }$$ can be used. the experiment with low-cost receivers for the sf-ds reveals (for the first time) that it has the potential to achieve comparable ambiguity resolution performance to that of a df-ss (l1, l2 gps), based on the survey-grade receivers.