That you can instead of having a base station use a “local wireless RTK correction service.” How do I do that with Ardupilot? What is the local wireless RTK correction service for southern california?
This service is called ntrip, you’ll need to find a local provider. Some are free, some are free to academic/students/hobbyists, and some are expensive. They’ll require a username and password, and will provide you a url to input to mission planner which treat it like rtk.