Method to calculate the power-flux-density mask radiated by NGSO constellation system

The emerging fleet of non-geo stationary orbit (NGSO) constellation is composed of up to thousands of NGSO satellites, with highly dynamic multi-dimensional characteristics such as in the domains of space, time, frequency spectrum, and coding, etc. Therefore, the time-varying interference is inevitably caused to other radio systems (or services) in the sharing frequency. The problem of how to calculate the maximum emission from the NGSO constellation is solved in this paper. The beam gain patterns of the NGSO system, the beam configuration and coverage, and the minimum separation angles at terminals (data points) are introduced on the basis of the calculation framework of ITU-R S.1503-3. The general method of the power-flux-density(PFD) mask can also simplify the calculation process. An example of PFD mask is simulated in this paper. It can be known from the analysis that the more detailed operating parameters of the system, especially such as the handover strategy, the interference avoidance or mitigation strategy to be obtained, the more accurate results can be simulated, which is closer to the real value of the system working. The method can be used to calculate the PFD envelope in order to participate in the calculation of the downlink equivalent PFD.