Interference mitigation using exclusion area between multi-beam satellite system and terrestrial system

In the frequency sharing situation between multi-beam satellite system and terrestrial radio system, the spectral efficiency would be enhanced by the frequency reuse scheme of two systems. However, the interference problem is also occurred since same frequency bands are used both the terrestrial radio system in a spot beam cell and the Earth stations in adjacent spot beams. Because the interference situation would be worse at the border area of the spot beam cell, the exclusion area concept is adopted to reduce the interference at the border area but it makes the degradation of the spectral efficiency by limiting the possible sub-bands used by the terrestrial radio system. This paper considers the optimum size of the exclusion area taking into account of both interference and spectral efficiency in the frequency sharing scenario. The study results show the variation of the interference and spectral efficiency with the widths of the exclusion area. The simulation is performed in the S band with the bandwidth of each sub-band is 5 MHz and frequency reuse factor, 7.