Patent attributes
An unmanned aerial vehicle (UAV) receives a set of Random Access preambles, determines its UAV status, and selects a Random Access preamble from the set of Random Access preambles. In some cases, the set of Random Access preambles are allocated for use by UAVs and are common to a plurality of neighboring cells. The UAV transmits the selected Random Access preamble to multiple neighboring cells. One of the neighboring cells that received the selected Random Access preamble transmits a Random Access Response to the UAV. The UAV determines which cell sent the Random Access Response, reselects to the cell that sent the Random Access Response, and transmits a Radio Resource Control (RRC) Connection Establishment Request to the reselected cell. Upon completion of a Random Access Channel (RACH) procedure, the reselected cell becomes the serving cell for the UAV.