Advanced Receiver Autonomous Integrity Monitoring(ARAIM),based on multi-constellation and multi-frequency of global navigation satellites system,which can provide vertical navigation in terminal approach,has attracted more attentions.The ARAIM user algorithm is based on the multiple hypothesis solution separation within the Integrity Support Message.The total probability of the monitored fault modes subsets must meet the integrity budget.In ARAIM baseline algorithm,the fault mode determination is an independently sequential structure.