Tile on OSB substrate in bedroom
I would not tile for a temporary surface. 
I would get a sheet of sanded 3/4”. 
If you only need a 4x 6 or 4x 8 lay the sheet down and cut the carpet at the edge.
Remove the cutout carpet and tack strip. Put plywood in the hole and use a few deck screws to hold the plywood in place. I might get some carpet threshold and lock the carpet down or use some screws and washers to hold the carpet in place. 

The plywood will hold up for a few years and be easy to remove. 
Tile will be more expensive take longer to put down after that all the work to remove and dispose of the debris. 

If you want a surface that will last a Formica sheet on top of the plywood will last a decade or more. And when pulled up could be used someplace else when done.