Abstract:

The traditional analytical method greatly underestimates the throughput capability of the system in low beam density scenario, and cannot reveal the capacity saturation phenomenon in high beam density scenario.To overcome the preceding problems, a new system simulation method was proposed to accurately evaluated the capacity density indicator of satellite constellation network and integrated satellite and terrestrial network, Based on this method, first, the capacity density of different longitude and latitude regions of the earth was evaluated.It could be observed that the capacity density of the same region varies greatly with the movement of the satellite, and the maximum capacity density was twice the minimum.Then, areas with higher visibility usually had higher capacity density.In high-frequency scenarios, the impact of atmospheric attenuation on capacity density could not be ignored.Finally, for the integrated satellite and terrestrial network, the evaluation results showed that the capacity density of cellular coverage and satellite coverage could differ by four orders of magnitude.In order to improved the capacity density of satellite constellation network, two technical paths were attempted: increasing the maximum number of illuminated beams and increasing the satellite scale.The results showed that the performance was better when the constellation scale was increased when the total beams of the constellation were the same.However, the two ways to increase the total number of beams in a constellation had an upper bound on capacity, and the marginal effect decreased significantly.Finally, a scheme to increase the gain of satellite antenna was proposed.The simulation results showed that the proposed scheme could significantly increase the capacity density of constellation.

Key words: large-scale LEO satellite constellations, capacity density, integrated satellite and terrestrial network