Rfid range increase

I’m trying to make a device that counts how many times my dogs go through a doggy door. As I have two dogs I want to be able to count each dog individually so the counter needs to be able to distinguish which dog is passing through the door an increment the appropriate counter. I have some Arduino knowlegde so it will be the base of my project. As a detector I was thinking of using a 125Khz RFID module - UART (Seeed Studio) SKU: SS113990014 but due to the range 50mm limitation I’m not sure if this will work. The plan is to put an rfid tag on each dogs collar and have the rfid module detect each dog as they pass through. To increase the range can I add multiple antenna’s or is there some other product that would suit this purpose better?
Additional info: the doggy door has an opening of 20cm x 15cm so the tag will diffinitely pass through there somewhere, the detector must be able to detect from the boundry of the door.
Thank you.

Hi Dap,

Thanks for your message! Sounds like a great project underway.

I’ve asked around here, and no one has on-hand experience with long range RFID. There seems to be a lot of intel on Google for the topic and we would be incredibly thankful if you could report back with what you’ve found and what products you might experiment with.