ELECTRONIC ANIMAL CONTAINMENT SYSTEM WITH DIRECTION OF APPROACH DETERMINATION

摘要

An electronic animal containment system with direction-of-approach determ ination, or direction-sensitive animal containment system. The direction-sen sitive animal containment system generally contains a transmitter unit conne cted to a wire loop bounding a containment area and a receiver unit carried by the animal. The direction-sensitive animal containment system of the pres ent invention generates a containment field having polarity and retains the polarity information when the containment field is sensed using a sensing co il optimized along the azimuth. The receiver unit also generates a gravity v ector to determine the orientation of the receiver unit. The gravity vector is combined with the containment field vector to produce a function that aut omatically yields a sensing coil output that is independent of the orientati on of the receiver unit. The polarity of the sensing coil output allows dete rmination of the direction from which the receiver unit is approaching the w ire loop.