Satellite navigation has all-weather, all-time, and low-cost advantages and has become the most widely used means of positioning, navigation, and timing (PNT) service since its inception. However, to avoid excessive reliance on the single means of satellite navigation at the application level, the concept of satellite-independent navigation technology has been proposed and received attention. How to accurately understand the relationship between satellite and satellite-independent navigation technologies has become a realistic and urgent issue. The technological characteristics and system positioning of satellite navigation are summarized in this study. The performances, costs, and application scenarios of typical satellite independent navigation technologies such as inertial navigation, matching navigation, and radio navigation (except for satellite navigation) are comparatively analyzed from a PNT system perspective. The relationship between satellite and satellite-independent navigation technologies is comprehensively analyzed. The overall positioning of satellite navigation as the most common demand satisfied and the core and cornerstone of the PNT system is further clarified. Additionally, the fusion efficiency is quantitatively analyzed. The scientific development of China's PNT system requires the innovative development of satellite-independent navigation technologies, and the deep integration of satellite and satellite-independent navigation technologies should be promoted. Moreover, the construction of low-orbit navigation systems should be accelerated to improve satellite navigation performance and maximizing system contribution.