Patent ID: 7616982
Filing Date: 2009-11-10
Classification: A61B

Abstract:
1. A method for determination of at least one location coordinate and at least one angular orientation coordinate of a mobile device that moves within or adjacent to at least one organ in a human or other animal body, the method comprising: (1) providing first and second spaced apart signal transmitting antennas, having index values i=1 and i=2, respectively, on the device, spaced apart along a selected axis of the device, and transmitting a first sequence and a second sequence of distinguishable signals at the first and second transmitting antennas, respectively, where the first and second transmitting antennas have location coordinates (x0+Δx0,y0+Δy0,z0+Δz0) and (x0−Δx0,y0−Δy0,z0−Δz0), respectively, a central location of the mobile device has location coordinates (x0,y0,z0), and the coordinate values x0, y0, z0, Δx0, Δy0, Δz0 are to be determined, and (x,y,z) are location coordinates in a selected Cartesian coordinate system; (2) receiving the first and second sequences of transmitted signals at least first, second, third and fourth spaced apart, non-coplanar signal receiving antennas, having index values j=1, 2, 3, 4, respectively, having substantially fixed and known location coordinates (xj,yj,zj), and being located adjacent to the body; (3) for each transmitted signal in each of the first and second sequences, providing an elapsed time of signal propagation Δt(i,j) between the first transmitting antenna (i=1) or second transmitting antenna (i=2) and the first, second, third or fourth signal receiving antenna (j=1, 2, 3, 4, respectively), where Δt(i,j) is expressed by a relation where c′ is a representative value of propagation of a transmitted electromagnetic signal within the body; (4) estimating the values Δx0, Δy0, Δz0, x0, y0 and z0 by the relations (5) interpreting the quantities (x1−x0, y1−y0, z1−z0) as location coordinates of the mobile device central location relative to location coordinates (x1,y1,z1) of the first receiving antenna; and (6) when D={(Δx0)