Abstract: Ground based augmentation system (GBAS) promotes the transition of air traffic management system from roadbed navigation to satellite-based navigation， in which B for multi-reference consistency check (MRCC) is the core algorithm in GBAS. The B correction algorithm is proposed based on the navigation satellites monitoring. The satellite pseudorange correction error S estimated is defined to monitor navigation satellites.With the methods of Gauss expansion-Shewhat， S warning threshold is derived. According to S value detected and fault satellites， a new collection of available satellites is formed， thus it is avoided that the whole receiver may be eliminated by the execution logic of MRCC because the B value cannot effectively reflect a large deviation of satellite pseudorange correction error estimated， which means the B values can be corrected. Experimental results show that the satellite fault can be monitored effectively in the new algorithm， and B value can be corrected， so as to improve the monitoring capacity of MRCC and increase system availability.

Key words: GBAS, collection of available satellites, MRCC, integrity