Abstract: Inductive transfer methods and structures combine, in a single system, at least two of the three functions of transferring power, communicating data, and sensing position with a vehicle on a guideway. A set of conductors is installed on the guideway to inductively couple a multiplicity of diverse signals with a corresponding set of conductors on the vehicle. The vehicle may be moving or stationary, and signals may be coupled in one or both directions. Coupling is effected without direct electrical contact, through a common region or gap, and the structures provide suitable and precise air gap control for the conductors effecting coupling of each signal. In addition, the windings are arranged with a topology and/or symmetry to cancel crosstalk between different signals.

Abstract: The invention provides guideway-based methods, apparatus and systems for tracking, sensing and communicating with objects, such as track and roadway vehicles, as well as waystations therefore. Such a system comprises a winding, a transmitter and a receiver. The winding is made up of two or more phased conductors connected to form one or more closed current paths. The phased conductors are conductive elements (such as wires) shaped or configured in periodically repeating patterns, such as saw tooths, sinusoids or square waves. The transmitter applies to at least one of the phased conductors a position-sensing signal which has an envelope that varies as a periodic function of a first position along (or relative to) the winding. The sensor, which is disposed at a second position along the winding, detects the position-sensing signals on the winding and generates a signal indicating the distance between the first and second positions.