Whether relative velocity between a transmitter and a receiver is higher than a predetermined amount is detected. This involves using a Doppler estimation technique to generate an estimate of Doppler spread, {circumflex over (f)}D(1), based on a received signal, and using an alternative velocity estimation technique to generate an estimate of velocity, {circumflex over (v)}, based on the received signal, wherein the alternative velocity estimation technique differs from the Doppler estimation technique. A plurality of estimates, including at least the estimate of Doppler spread and the estimate of velocity, are used to detect whether the relative velocity between the transmitter and the receiver is higher than the predetermined amount. The alternative velocity estimation technique may, for example, be a second Doppler estimation technique that differs from the other Doppler estimation technique.