Typically satellites move at a speed of about 26.000 kilometres per hour, therefore one could think that the mobile on the ground is a stationary, whereas the satellite is moving, and with "h" equal to 1.500 kilometres, the satellite has a linear ground speed of about 7,1 kilometres per second. Inter-satellite hand over are required if the signal quality falls below a certain threshold, when the distance between the satellite and user has become too large, the signal carrier to-interference-ratio is too low, or when other users are using the same channel causing co-channel interference.

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