Calculational method for assessing the probability distribution of an equivalent power flux density
JIN jin1,2, LIN Ziqiao3, YAN Jian1,2, KUANG Linling1,2
1. Beijing National Research Center for Information Science and Technology, Beijing 100084, China; 2. School of Information Science and Technology, Tsinghua University, Beijing 100084, China; 3. Department of Electronic Engineering, Tsinghua University, Beijing 100084, China
Abstract：EPFD (equivalence power flux density) is an important indicator for evaluating the interference of a NGSO (non-geostationary orbit) constellation system to a GSO (geostationary orbit) system. The EPFD probability distribution is usually obtained by extrapolating the satellite orbit position and compile statistics the occurrence time proportion of various EPFD values. For mega-constellation systems like Starlink, the traditional extrapolation method to calculate EPFD will involve long, inefficient simulations. This paper presents a simplified method to calculate the EPFD probability distribution. Constellation snapshots are generated by placing reference satellites at various locations in a region to obtain all possible satellite distributions. The snapshot probabilities are then characterized by the occurrence probabilities of the reference satellites, and the EPFD generated for various snapshots used to obtain the EPFD probability distribution. Simulations show that this method can be applied to both traditional constellations with fewer satellites and to mega-constellations. These simulations have the same accuracy as the traditional method, but with higher computational efficiencies.
靳瑾, 林子翘, 晏坚, 匡麟玲. 计算等效功率通量密度概率分布的方法[J]. 清华大学学报（自然科学版）, 2022, 62(1): 172-178.
JIN jin, LIN Ziqiao, YAN Jian, KUANG Linling. Calculational method for assessing the probability distribution of an equivalent power flux density. Journal of Tsinghua University(Science and Technology), 2022, 62(1): 172-178.
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2022, Vol. 62 
