Sending a trigger pulse by RF

If the remote is to be battery powered, it will go through a few phases; first, the carrier is established (during this phase, the receiver will have AGC fluctuations), then a signal is sent (something like a tone burst) and received (by a filter and trigger that rejects noise but not the signal). The AGC needs settling time, and the tone decoder will want a dozen or more cycles to detect (but can probably drop its output quickly when the signal is interrupted), so you'll actually get a 'receiver-end' time signal a bit AFTER hitting the button on the remote. Be prepared for this (and control that latency at all phases of the design).