WIY
Is the wifi AP yours? You can filter out the smartphone MAC address from there, and then you will be able to connect with your laptop but not with your smartphone. I understand that might not be a good solution if you move a lot and often use the wifi in shops, cafes and the like. But it would work if you use the laptop for work and don’t want to use the smartphone on the same wireless network, that you have the password for.
Editing the antenna parameters, or renaming the antenna configuration files, would make the wifi completely nonfunctional (unless/until they are edited again). While everything would remain completely open, most of us do not stand a chance to reverse that from memory.
You probably should also consider how to avoid accessing the internet from the cellular network. Cost is a good deterrent but not a perfect filter 🙂