Patent attributes
Disclosed is a method of measuring time of arrival of a signal transmitted from a transmitter (120) to a receiver (110-n). The method comprises: modulating a plurality of narrowband signal portions onto different carrier frequencies; transmitting, by the transmitter, each modulated signal portion to the receiver; receiving, by the receiver, the transmitted signal portions; estimating the channel impulse response by combining (610) the received signal portions; and measuring (620) the time of arrival using the estimated channel impulse response. Further disclosed is a method of measuring a time of arrival of a signal transmitted from a transmitter to a receiver. The method comprises: estimating a noise level (1310) in an impulse response of a channel between the transmitter and the receiver; finding a first peak (1330) in the channel impulse response that is not noise or a side lobe of a subsequent peak, using the estimated noise level; and measuring the time of arrival (1220) using the first peak.