Garmin, the GPS maker, does have this:
Amazon.com: Garmin Astro DC-30 GPS Dog Tracking...
Yes, it's a special collar with a GPS transmitter.
PetTronix also has one:
GPS Pet Collar : PetTronix
This company appears to have something with a phone app add-on:
GPS Pet Locator, GPS Dog Collar, GPS Pet Tracker, SpotLite, SpotLight - Securus Inc.