Patent ID: 7679561

Claim:
A method for positioning using a multipath wireless signal, the method comprising the steps of: receiving a plurality of wireless signals comprising multipath signals; processing the plurality of wireless signals to identify at least one indirect path; determining an initial estimate for {r}, wherein {r} is a position of a receiver; determining initial estimates of and {w n , τ 0n } for the at least one indirect path based on a parametric model relating {r} to a length of the at least one indirect path, the parametric model assuming, without prior knowledge of a local infrastructure or propagation channels associated with the at least one indirect path, that at least one multipath signal has experienced at least one specular reflection off a planar surface along the at least one indirect path before reaching the receiver; receiving a subsequent plurality of wireless signals comprising multipath signals; and updating the initial estimates of {r} and {w n , τ 0n } using a nonlinear filter and the subsequent plurality of wireless signals applied to that filter, wherein w n is a unit vector in a direction of the at least one indirect path from a reflecting surface closest to the receiver and τ 0n is a scalar geometry-dependent offset associated by the parametric model to the length of the at least one indirect path.