They use 433mhz. The same as garage door openers and home weather stations.

To achieve the longest battery life possible they put the shade into a "sleep" current mode. It "wakes up" when RF energy is detected and it evaluates the signal to see if it is a valid Qmotion command.

If the command is valid it executes the command. Otherwise the shade goes back into "sleep mode".

The problems start when you have a lot of RF waking the shade up too often. This can greatly shorten the battery life.

Live on the beach? Neighbors all have home weather stations? Could be a problem.

Parking garage nearby? All those key fobs transmitting could be a problem.