A transmitter subsystem periodically transmits ranging signals at transmit times, and a receiver subsystem receives the ranging signals at receive times within a receiver window having an adjustable time duration. A real-time position of a mobile device supporting one of the subsystems is determined based on differences between the receive and transmit times. An expected arrival time for the transmitted ranging signals is determined based on the real-time position of the mobile device. Each receive time is compared with the expected arrival time to obtain a consistency rate of the ranging signals that are received by the receiver subsystem directly from the transmitter subsystem. The time duration of the receiver window is dynamically adjusted based on the consistency rate.