The invention discloses a performance evaluation method and
system for a transmission link of a
satellite-ground convergence network and a medium, and the method comprises the steps: comparing the
signal to interference plus
noise ratio of a direct transmission link in the
satellite-ground convergence network with a preset reference value, and determining the direct transmission link or a
relay link in the
satellite-ground convergence network as the transmission link according to a comparison result. The calculation complexity of
system implementation is reduced, and the
system performance of the satellite-ground fusion network under multi-
relay multi-link transmission and the high-complexity calculation degree of system implementation are balanced; after the transmission link is determined, the
outage probability of the transmission link is calculated according to the
signal to interference plus
noise ratio of the transmission link, the complexity and difficulty of
outage probability calculation can be reduced, the system performance of the selected transmission link is quantitatively evaluated based on the
outage probability, the calculation difficulty of quantitative evaluation of the system performance is further reduced, and the system performance can be accurately evaluated.