Sentence examples for code observation from inspiring English sources
Due to the satellite and constellation deployment design, the variation pattern of multipath effect in BeiDou Navigation Satellite System (BDS) code observation is different from GPS.
The amplitude of systematic multipath variation (SMV) exists in multipath combination series may exceed 0.5 m for some geostationary earth orbit (GEO) satellites, which is larger than the normal noise level of GPS code observation.
In such situations, a code "observation for thrombosis" is supposed to be used but was not.
The final observation file with all three observation record sources (lifestyle/clinical, laboratory and Read code observation data) had 94.2 % of observations records and 75.2 % of observation terms mapped to either the LOINC or SNOMED-CT dictionaries.
In this study, phase observations with high precision are directly used instead of phase smoothed code observations.
After that, variances of phase and code observations for different orbits satellites can be estimated, then the stochastic model specific for BDS can be constructed in real time.
The datasets obtained from the experiments have also been utilized to perform combined GPS/COMPASS SPP on an epoch-by-epoch basis using unsmoothed single-frequency code observations.
The results show that the noise level of the GPS L1/L2 signals and the negative impact of multipath errors on the GPS pseudo-range observations for the L1/L2 signals are greater than those of Galileo E1/E5a signals, resulting in the residuals of GPS ionosphere-free code observations larger than those of Galileo code observations.
The analysis of dispersion of undifferenced pseudorange observations caused by noise and multipath effect has confirmed slightly higher precision of code observations on the first in respect to second frequency for both systems.
BDS code observations already allow a standalone positioning with RMS accuracy of at least 22 m using BDS broadcast ephemeris, while the accuracy is at least 5 m using BDS precise ephemeris.
Several precise positioning applications which use code observations are severely affected by these code biases.
