Patent ID: 7653004

Claim:
A method of estimating time of arrival (TOA) in an ad-hoc communications network, comprising the steps of: sending a ranging message from a first node to a second node; receiving a signal at the second node; measuring the TOA of the received signal; correlating the received signal with a reference signal to obtain a measured correlation function; estimating a phase delay of the received signal utilizing the measured correlation function; constructing a reference correlation function based on the amplitude and the phase delay of the measured correlation function; calculating a score indicating quality of the measured TOA, based on the reference correlation function and the measured correlation function, wherein the calculated score is proportional to the inverted sum of the difference between the reference correlation function and the measured correlation function; and biasing an error by taking the difference between the reference correlation function and the measured correlation function and multiplying the difference by a power of the amplitude of the highest reference correlation function and the measured correlation function.