There have been a few chats around it, such as this
But I thonk there is an alternate path you can go down to achieve the same result, just modified a little for a pet reader.
I totally understand why you would want that range.
I think the closest you will get to 30cm read range would be using what @Rosco used for his door mat, his desk foot reader and his chair.
His Chair was reading a FlexEM though, and thats not going into a dog, but the Doormat and Desk reader were xSeries.
You witth need to build a circuit to unlock the doggy door, but it shouldnt bee to difficult.
What size are your dogs?
This will help determine the location of the reader.
Wait one, I will dig out the relevant posts, wont be long…
