Patent ID: 7057556

Claim:
A method for determining a time difference of arrival of a single signal transmitted from a transmitting unit and received at two or more receiving sites, the method comprising: (a) transforming the signal received at a first site to a frequency domain representation comprising first component signals each first component signal having a frequency and a phase angle parameter and transforming the signal received at a second site to a frequency domain representation comprising second component signals each second component signal having a frequency and a phase angle parameter; (b) operating in the frequency domain, determining a Hermitian product of first and second component signals having a same frequency parameter, wherein a frequency parameter of the Hermitian product comprises the same frequency parameter; (c) operating in the frequency domain, determining a phase angle parameter of each Hermitian product determined at the step (b); (d) determining a relationship between the phase angles parameter and the frequency parameter for a plurality of Hermitian products; and (e) determining the time difference of arrival from the relationship.