Embodiments are directed to avoiding interference between a maritime mobile radio network and a mobile radio network provided at a fixed position relative to the maritime mobile radio network. A current geographic position of the maritime network is determined. A minimum separation distance to be maintained between the two networks is determined based on the geographic position. A current separation distance is predicted based a signal detected from the fixed-position network. When the predicted separation distance is less than the minimum separation distance and the detected signal is determined to be persistent, the maritime network is turned off. The detected signal may be determined to be persistent when it is continuously detected over a predetermined time period and has sufficient signal energy for sustaining a cellular telephone call.