GRGS Dynamical modelling of GPS orbits and SLR Residuals

Authors : H. Capdeville (CLS)
               S. Loyer (CLS)
               F. Perosanz (CNES)


The GPS orbit produced by GRGS using GINS
Software in the framework of our IGS activities 
are affected by a radial bias relatively to IGS 
combined ones (around 1 ppb). This bias is 
linked to the dynamic modelling we use for our 
orbit. One interesting point, is that the 
dynamical model we use is different than 
classical one used by most of the IGS 
Analysis centre.  An another point is that it 
seems that our observed radial bias is more 
compatible with the SLR residuals on GPS 35 & 
36. Taking advantage of the recent 
ILRS intensive campaign we propose 
to present in detail our dynamical modelling 
and the Laser residuals for different 
configurations relatively to IGS ones.