Contribution of the BDS to availability and reliability improvement: A case study of dam surface displacement monitoring in China

Abstract

The GPS-only system is limited in dam surface monitoring because of its low availability and reliability due to the visible satellites are not enough. This dilemma is expected to be solved through incorporating the China's BeiDou System (BDS). This contribution will quantitatively analyse the availability and reliability improvements from DBS in different shielding situations of dams. The analysis is conducted through simulating a dam obstruction with different size, azimuth and distance to receiver. The similar experiments are simulated in the area across China in order to explore these contributions in different locations. Quantitative analysis results derive conclusions: (1) In most areas, the availability improved from 50% of GPS-only to 95% of BDS + GPS when most of the GEO/IGSO satellites are not blocked, and to 70% even when most of GEO/IGSO satellites are blocked. (2) The average MDBs can be reduced by half when most of the GEO/IGSO satellites are not blocked, and by 10% even when most of GEO/IGSO satellites are blocked. Keywords: Dam surface monitoring, BDS, Availability, Reliability