A time-of-propagation distance-determining method involves sending a probe request from a handset to an AP and receiving a return ACK. The time it takes for the probe request to propagate to the AP, the turnaround time, and the time it takes the ACK to propagate back to the handset is measured on the handset. The turnaround time is subtracted from the measured time, and the result is used to make a distance determination. In order to reduce power consumption, the “lowest overall transmit energy” setting that will give acceptable reception of a probe request sent by the handset to the AP station is determined. The lowest overall transmit energy setting involves a bit rate setting and a transmit power setting. The lowest overall transmit energy setting is used to send probe requests when probe requests are sent from the handset in carrying out a time-of-propagation distance-determining transaction.