DETERMINING DIRECTION OF AN OBJECT USING LOW FREQUENCY MAGNETIC FIELDS

摘要

A method for determining direction of travel of a tag is described. The method includes a tag that receives sample signals from two spatially separate LF magnetic fields generated by an exciter. The received signal strength indicator (RSSI) data associated with each of the sample signals is determined. A first RSSI profile is created for the first LF magnetic fields. A second RSSI profile is created for the second LF magnetic fields. The first and second RSSI profiles are compared to determine a direction of travel of the object. A tag, an exciter and a computer readable medium are configured to facilitate the method.

主权项

1. An exciter comprising:
a two directional coil comprising a first loop and a second loop, the first loop positioned orthogonal to and coaxial with the second loop; and a control circuit coupled to the two directional coil and configured to:
activate the first loop and the second loop to create a first low frequency (LF) magnetic field and a second LF magnetic field, respectively;modulate the first magnetic field with a loop identifier for identifying the first loop; andmodulate the second magnetic field with a loop identifier for identifying the second loop.