On the relation of GNSS phase center offsets and the terrestrial reference frame scale: a semi-analytical analysis

Abstract Phase center offsets (PCOs) of global navigation satellites systems (GNSS) transmit antennas along the boresight axis introduce line-of-sight-dependent range changes in modeling GNSS observations that are strongly correlated with estimated station heights. As a consequence, adopted PCOs impact scale GNSS-based realizations terrestrial reference frame (TRF). Vice versa, TRF require corrections to antenna for consistent observation modeling. Early studies have determined an approximate value $$\alpha =-0.050$$ α = - 0.050 ratio height and satellite PCO GPS orbit determination phase adjustment. However, this is mainly empirical limited information available on actual PCO-scale relation how it influenced by other factors. In view recurring need adjust IGS models new ITRF scales, semi-analytical model developed determine values $$ four current GNSSs from first principles without network data processing. Given close coupling angle zenith angle, essentially compensated combination height, troposphere delay, receiver clock offset. such, depends not only orbital altitude considered but also elevation-dependent distribution their weighting, as well elevation mask tropospheric mapping function. Based model, representative _\text {GPS}=-0.051$$ GPS 0.051 , {GLO}=-0.055$$ GLO 0.055 {GAL}=-0.041$$ GAL 0.041 {BDS-3}=-0.046$$ BDS-3 0.046 derived GPS, GLONASS, Galileo, BeiDou-3 at $$10^\circ 10 ∘ cutoff angle. These may vary $$\varDelta \alpha \approx 0.003$$ Δ ≈ 0.003 depending specific assumptions processing parameters precise or point positioning. Likewise about $$\pm ± can be observed when varying between $$5^\circ 5 $$15^\circ 15 .