Antenna-gain diversity is obtained in the following manner. A link monitoring system monitors all inbound and outbound calls of a carrier network collecting data such as calling and called telephone directory numbers, and a termination status for at least each inbound call to a calling number. Because the EH11\u03b4 resonance mode has nulls in a direction of longitudinal extension of the dielectric resonator, a plurality of antenna can be placed end-to-end so as to form an array with reduced coupling between adjacent antennas and with vertical polarisation, which is desirable for mobile communications applications.