Help/Suggestions on wireless tag schematic

[behrendfry]

I made a door for my pets to enter and exit the garage into the backyard. The door has a small motor on it that when it is sent a high signal it will open the door to a limit and then hold it there until it sees a low signal then it releases and a simple spring pulls the door back shut. I want to utilize the concept of theft tags used in dept stores on clothing and have a small tag attached to the pets collar and when it is within range it will activate the receiver to send a signal to open the door, much like theft tags set off an alarm when they are within the set range of the door that has the receiving unit. Any suggestions on a simple circuit/schematic that will allow me to do this would be very helpful.

 

[tkvenki]

Is an RF solution feasible...??

HI...

I think you can use an RF solution for that.
I guess a RF transmitter attached to the coller of your pet...
will keep on sending the signals....
And when it is in the proximity of your garage door...
this signal can be detected....

Venkatesh T.K
India.