We have a Petsafe Stay and Play wireless dog fence at our house which we like very much. However the yl would like to increase the radius of the containment field, due to the shape of our lot and the location of our house I already have the transmitter located such to give the maximum range without let the dog get into the neighbors yard. It used to be larger but a certain hound dug a hole where they shouldn't have and now the range is smaller...
Attached FileIn my mind I thought the fence used WiFi frequencies and I thought I might be able to unplug the stock antenna and make a new one with more of a cartoid pattern that would move field into the front yard and reduce the range in the back. I didn't want to take the transmitter apart so I did some looking online. I started by looked up the
FCC ID (grantee code: KE3, product code:-3001070) and found images of the antenna and test data giving the operating frequency. It isn't a WiFi device after all, it operates on 18.7kHz.
Attached FileNext I wanted to know more about how it worked so I did an IP search, I found
US7142167B2.
Attached FileThe present invention is based on near-field signal detection of the total power in a low-frequency (10 kHz to 100 kHz), quasi-static 3-axis magnetic field. Quasi-static magnetic fields are generally known to be immune to the field-strength variability problems that can occur in systems based on propagating RF fields because of multipath reflections and severe field distortion by proximate conducting masses such as body tissue.
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The prior art devices used a single axis field generator and required a multi-axis receiver. This one uses a multi-axis transmitter and a single axis receiver for better battery life.
I thought this was interesting and wasn't at all what I was expecting. At this point I've given up on being able to beam shape the antenna and will pursue other avenues but thought I'd post about it any way and the low frequency magnetic field bit was neat.