A controller of a layered radio environment map of a wireless communication system. The controller configures a mobile terminal to make a measurement associated with a wireless signal from the mobile terminal to a base station. The mobile terminal constructs a minimization of drive test (MDT) measurement report from the measurement, and uses a network connection to transmit the MDT measurement report. The network connection is selected based at least in part on information related to the mobile terminal. As such, the power consumption in the mobile terminal is minimized.