Satellite Laser Ranging Biases and Terrestrial Reference Frame Scale Factor

We examine the impact of the strategy adopted regarding range biases on Satellite Laser Ranging data processing results. More especially, we test the stability of the weekly Terrestrial Reference Frame scale factors computed w.r.t. ITRF2000 according to the two different strategies which are studied in this paper. In the first approach, range biases are not considered in the data processing. In the second approach, we use a temporal de-correlation method to rigorously estimate all station range biases. The first approach provides weekly scale factors with a piece-wise behavior. More precisely, the time series exhibit a drift of -2.5 +/- 0.2 mm/yr between 2001.0 and 2006.0 and provide a RMS of 5.2 mm. The second approach, which makes the most physical sense, really provides regular weekly scale factors. Indeed, between 2001.0 and 2006.0, these series exhibit a drift of -0.7 +/- 0.2 mm/yr and the RMS of the whole time series is 3.7 mm. Moreover, less discontinuities are detected in the station position residual time series provided by the second approach than in those produced with the first approach.