Hello, I would like to know which is best and less cost in communication (Indoor)

I'm gonna create a follow me robot but instead of me(human) the one it follows.. a remote which is wireless and i will use nRF24L01 for its wireless communication, and my problem is which is best to use in indoor to use in "follow me", GPS or Bluetooth module? or other wireless communication?

by the way... the remote has two option... it can be switch to manual and follow.

I hope you can give a piece of advice?

thanks

 

I played with this GPS Module with Ceramic Antenna for DIY Handheld Positioning System for $7.86
http://www.dx.com/p/open-smart-gps-...ino-apm2-5-flight-control-480918#.WiDKElWnH4Y
Over a period of 5 minutes, without moving, the Latitude & Longitude numbers go up and down independently. It seems like it is wandering around but stays within a 25 feet diameter circle. I guess that is pretty good trying to triangulate my location from 3 or more moving objects in space. But that is not good enough for GPS controlled follow me robot.

 

As a simple reality check, try to think of any device that has a similar function.

The nature of radio signals make this a difficult proposition at the scale you are considering.
Radio direction finding works great over Km's distance, but not over a few meters.