With the rapid development of technology and practical deployment of hypersonic weapon, the United States has carried out a new plan of building Tracking Layer of National Defense Space Architecture (NDSA). Firstly, the main design parameters of tracking layer were introduced; Secondly, the analysis model of tracking layer constellation coverage performance, detection capability and tracking performance were established; Finally, the performance of tracking layer was analyzed through simulation and calculation, and the core capabilities such as the minimum satellites number of the whole constellation, detection sensitivity and optimal global target tracking accuracy were deduced. The analysis results have important reference value for the research of data processing algorithm and the design of similar payload and constellation.