Patent ID: 7965237

Claim:
A method for determining current position location information of a wireless station using at least a first and a second mobile wireless sensor, comprising the steps of: receiving a first RF transmission segment from the wireless station at the first mobile wireless sensor at a first predetermined position location and a first time instant; receiving a second RF transmission segment from the wireless station at the second mobile wireless sensor at a second predetermined position location and at approximately the same first time instant; correlating the first RF transmission segment with the second RF transmission segment to generate a first correlation data segment; determining a first time difference of arrival between a first time at which the first mobile wireless sensor receives the first RF transmission segment at the first predetermined position location and a second time at which the second mobile wireless sensor receives the second RF transmission segment at the second predetermined position location in response to a correlation peak from the first correlation data segment; determining a first surface in three-dimensional space that defines first possible position locations of the wireless station based on at least the first time difference of arrival, the first predetermined position location and the second predetermined position location; receiving a third RF transmission segment from the wireless station at the first mobile wireless sensor at a third predetermined position location and a second time instant; receiving a fourth RF transmission segment from the wireless station at the second mobile wireless sensor at a fourth predetermined position location and at approximately the same second time instant; correlating the third RF transmission segment with the fourth RF transmission segment to generate a second correlation data segment; determining a second time difference of arrival between a third time at which the first mobile wireless sensor receives the third RF transmission segment at the third predetermined position location and a fourth time at which the second mobile wireless sensor receives the fourth RF transmission segment at the fourth predetermined position location in response to a correlation peak from the second correlation data segment; determining a second surface in three-dimensional space that defines second possible position locations of the wireless station based on at least the second time difference of arrival, the third predetermined position location and the fourth predetermined position location; and determining intersected possible position locations of the wireless station based on an intersection of the first and second surfaces in three-dimensional space.