Sending RF signals upon a condition

Hello,

I'm developing a robot. one of its functionalities is to send a signal to some receiver whenever it arrives a specific location.
I'm thinking of putting a tape of specific color (e.g. red) on the floor of that location, and whenever the robot snese the color (using line tracking sensor) it sends the signal.
The issue is i'm new to this field and I need help in identifying the software and hardware requirements. Any help on that? or another simpler solution?

Thank you