Patent Document ID: 9310460
Application ID: 13627712
Patent Status: 1

Claim One:
1. A method for searching for a transmitter with a detector and a position determining device for determining at least one orientation variation of the detector, the detector comprising at least a first and a second antenna for receiving a transmit signal of the transmitter, wherein the transmit signal includes pulses emitted with a certain transmit pulse period, the method comprising the following steps: a) detecting the vectorial magnetic field strengths (Hv 1 meas , Hu 1 meas , Hv 2 meas , Hu 2 meas ) of the field emitted by the transmitter in at least two dimensions for at least a first and a second measurement point relative to a reference axis of the detector carried by a searcher; and b) detecting at least one orientation difference (φ 2 −φ 1 ) between at least the first and the second measurement point; wherein the method further comprises the following steps for determining a position vector (p i ) representing the location of at least one measurement point relative to the location of the transmitter; c) assuming at least one geometric relation between at least the first and the second measurement point; d) assuming initial values for the position vector (p i ) in at least two dimensions in at least the first and the second measurement point; e) assuming an orientation (α) of a transmitting antenna of the transmitter related to a first presettable reference direction; f) calculating the vectorial magnetic field strengths (Hv 1 calc , Hu 1 calc , Hv 2 calc , Hu 2 calc ) of the field emitted by the transmitter in at least two dimensions for at least the first and the second measurement point based on the assumptions according to the steps c) to e) as well as the detected orientation difference (φ 2 −φ 1 ) according to step b); g) calculating an error vector (g) between the vectorial magnetic field strengths detected in step a) and the vectorial magnetic field strengths calculated in step f); and h) numerically minimizing a function (E) of the error vector (g) calculated in step g) by altering the assumptions made in steps c) to e) until a presettable tolerance threshold (tol) for the function (E) of the error vector (g) is undercut.